diff --git a/contrib/unifdef/.gitignore b/contrib/unifdef/.gitignore
new file mode 100644
index 000000000000..55ca2f341b7c
--- /dev/null
+++ b/contrib/unifdef/.gitignore
@@ -0,0 +1,7 @@
+Changelog
+unifdef
+unifdef.exe
+unifdef.txt
+unifdef-*
+version.h
+version.sh
diff --git a/contrib/unifdef/.travis.yml b/contrib/unifdef/.travis.yml
new file mode 100644
index 000000000000..39aa4292de14
--- /dev/null
+++ b/contrib/unifdef/.travis.yml
@@ -0,0 +1,59 @@
+language: c
+
+sudo: false
+
+os:
+  - linux
+  - osx
+
+compiler:
+  - gcc
+  - clang
+
+matrix:
+  include:
+    ## Ubuntu 14.04 Trusty (beta), sudo required!
+    - os: linux
+      dist: trusty
+      sudo: required
+      compiler: gcc
+      env: TRUSTY="yes"
+    - os: linux
+      dist: trusty
+      sudo: required
+      compiler: clang
+      env: TRUSTY="yes"
+    ## MinGW / wine
+    - os: linux
+      sudo: required
+      compiler: i586-mingw32msvc-gcc
+      env: BUILD_MINGW="yes"
+  allow_failures:
+    - compiler: i586-mingw32msvc-gcc
+
+install:
+  - env | grep -v "encrypted" | LC_ALL=C sort
+  - if test "${BUILD_MINGW}" = "yes"; then
+      sudo apt-get -qq update &&
+      sudo apt-get -qq install wine;
+    fi
+
+script:
+  - if test "${BUILD_MINGW}" != "yes"; then
+      make &&
+      make test &&
+      make release;
+    else
+      export CC=i586-mingw32msvc-gcc;
+      echo -e '#!/bin/bash\nexec wine $0.exe "$@"' > unifdef;
+      chmod ugo+x unifdef;
+      make version.h &&
+      make -f win32/Makefile.mingw test;
+    fi
+
+branches:
+  only:
+    - master
+    - next
+    - /^travis.*/
+    - /^tmp.*/
diff --git a/contrib/unifdef/COPYING b/contrib/unifdef/COPYING
new file mode 100644
index 000000000000..ae0ab7eeb717
--- /dev/null
+++ b/contrib/unifdef/COPYING
@@ -0,0 +1,85 @@
+unifdef copyright licence
+-------------------------
+
+All files in this package are distributed under the two-clause BSD
+copyright licence, except for the manual page unifdef.1 and the
+portability support code in the FreeBSD subdirectory, which all have
+a three-clause BSD copyright licence.
+
+Unifdef was derived from software contributed to Berkeley by Dave
+Yost. It was rewritten to support ANSI C by Tony Finch. The original
+version of unifdef.c carried the four-clause BSD copyright licence.
+None of its code remains in this version (though some of the names
+remain) so it now carries the more liberal two-clause licence.
+
+Unless otherwise stated, the files in this package are:
+
+  Copyright (c) 2002 - 2020 Tony Finch <dot@dotat.at>
+
+unifdefall.sh is:
+
+  Copyright (c) 2002 - 2013 Tony Finch <dot@dotat.at>
+  Copyright (c) 2009 - 2010 Jonathan Nieder <jrnieder@gmail.com>
+
+Some files in the tests directory are:
+
+  Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+
+The two-clause BSD copyright licence applying to all the above files is:
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions
+  are met:
+  1. Redistributions of source code must retain the above copyright
+     notice, this list of conditions and the following disclaimer.
+  2. Redistributions in binary form must reproduce the above copyright
+     notice, this list of conditions and the following disclaimer in the
+     documentation and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+  SUCH DAMAGE.
+
+The three-clause BSD copyright licence for the manual page unifdef.1
+and the portability support code from FreeBSD is below. The fourth
+advertising clause that used to appear between clauses 2 and 3 was
+rescinded by the University of California Berkeley in 1999.
+ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
+
+  Copyright (c) 1985 - 1994
+	The Regents of the University of California.  All rights reserved.
+  Copyright (c) 2002 - 2012 Tony Finch <dot@dotat.at>.  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions
+  are met:
+  1. Redistributions of source code must retain the above copyright
+     notice, this list of conditions and the following disclaimer.
+  2. Redistributions in binary form must reproduce the above copyright
+     notice, this list of conditions and the following disclaimer in the
+     documentation and/or other materials provided with the distribution.
+  3. Neither the name of the University nor the names of its contributors
+     may be used to endorse or promote products derived from this software
+     without specific prior written permission.
+
+  THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+  ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+  SUCH DAMAGE.
+
+- end -
diff --git a/contrib/unifdef/FreeBSD/err.c b/contrib/unifdef/FreeBSD/err.c
new file mode 100644
index 000000000000..9589fced5b26
--- /dev/null
+++ b/contrib/unifdef/FreeBSD/err.c
@@ -0,0 +1,138 @@
+/*-
+ * Copyright (c) 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "unifdef.h"
+
+void
+err(int eval, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	verrc(eval, errno, fmt, ap);
+	va_end(ap);
+}
+
+void
+verr(int eval, const char *fmt, va_list ap)
+{
+	verrc(eval, errno, fmt, ap);
+}
+
+void
+errc(int eval, int code, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	verrc(eval, code, fmt, ap);
+	va_end(ap);
+}
+
+void
+verrc(int eval, int code, const char *fmt, va_list ap)
+{
+	fprintf(stderr, "%s: ", _getprogname());
+	if (fmt != NULL) {
+		vfprintf(stderr, fmt, ap);
+		fprintf(stderr, ": ");
+	}
+	fprintf(stderr, "%s\n", strerror(code));
+	exit(eval);
+}
+
+void
+errx(int eval, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	verrx(eval, fmt, ap);
+	va_end(ap);
+}
+
+void
+verrx(int eval, const char *fmt, va_list ap)
+{
+	fprintf(stderr, "%s: ", _getprogname());
+	if (fmt != NULL)
+		vfprintf(stderr, fmt, ap);
+	fprintf(stderr, "\n");
+	exit(eval);
+}
+
+void
+warn(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vwarnc(errno, fmt, ap);
+	va_end(ap);
+}
+
+void
+vwarn(const char *fmt, va_list ap)
+{
+	vwarnc(errno, fmt, ap);
+}
+
+void
+warnc(int code, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vwarnc(code, fmt, ap);
+	va_end(ap);
+}
+
+void
+vwarnc(int code, const char *fmt, va_list ap)
+{
+	fprintf(stderr, "%s: ", _getprogname());
+	if (fmt != NULL) {
+		vfprintf(stderr, fmt, ap);
+		fprintf(stderr, ": ");
+	}
+	fprintf(stderr, "%s\n", strerror(code));
+}
+
+void
+warnx(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vwarnx(fmt, ap);
+	va_end(ap);
+}
+
+void
+vwarnx(const char *fmt, va_list ap)
+{
+	fprintf(stderr, "%s: ", _getprogname());
+	if (fmt != NULL)
+		vfprintf(stderr, fmt, ap);
+	fprintf(stderr, "\n");
+}
diff --git a/contrib/unifdef/FreeBSD/getopt.c b/contrib/unifdef/FreeBSD/getopt.c
new file mode 100644
index 000000000000..eb9b0c507875
--- /dev/null
+++ b/contrib/unifdef/FreeBSD/getopt.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 1987, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "unifdef.h"
+
+int	opterr = 1,		/* if error message should be printed */
+	optind = 1,		/* index into parent argv vector */
+	optopt,			/* character checked for validity */
+	optreset;		/* reset getopt */
+char	*optarg;		/* argument associated with option */
+
+#define	BADCH	(int)'?'
+#define	BADARG	(int)':'
+
+static char EMSG[] = "";
+
+/*
+ * getopt --
+ *	Parse argc/argv argument vector.
+ */
+int
+getopt(int nargc, char *nargv[], const char *ostr)
+{
+	static char *place = EMSG;		/* option letter processing */
+	const char *oli;			/* option letter list index */
+
+	if (optreset || *place == 0) {		/* update scanning pointer */
+		optreset = 0;
+		place = nargv[optind];
+		if (optind >= nargc || *place++ != '-') {
+			/* Argument is absent or is not an option */
+			place = EMSG;
+			return (-1);
+		}
+		optopt = *place++;
+		if (optopt == '-' && *place == 0) {
+			/* "--" => end of options */
+			++optind;
+			place = EMSG;
+			return (-1);
+		}
+		if (optopt == 0) {
+			/* Solitary '-', treat as a '-' option
+			   if the program (eg su) is looking for it. */
+			place = EMSG;
+			if (strchr(ostr, '-') == NULL)
+				return (-1);
+			optopt = '-';
+		}
+	} else
+		optopt = *place++;
+
+	/* See if option letter is one the caller wanted... */
+	if (optopt == ':' || (oli = strchr(ostr, optopt)) == NULL) {
+		if (*place == 0)
+			++optind;
+		if (opterr && *ostr != ':')
+			(void)fprintf(stderr,
+			    "%s: illegal option -- %c\n", _getprogname(),
+			    optopt);
+		return (BADCH);
+	}
+
+	/* Does this option need an argument? */
+	if (oli[1] != ':') {
+		/* don't need argument */
+		optarg = NULL;
+		if (*place == 0)
+			++optind;
+	} else {
+		/* Option-argument is either the rest of this argument or the
+		   entire next argument. */
+		if (*place)
+			optarg = place;
+		else if (nargc > ++optind)
+			optarg = nargv[optind];
+		else {
+			/* option-argument absent */
+			place = EMSG;
+			if (*ostr == ':')
+				return (BADARG);
+			if (opterr)
+				(void)fprintf(stderr,
+				    "%s: option requires an argument -- %c\n",
+				    _getprogname(), optopt);
+			return (BADCH);
+		}
+		place = EMSG;
+		++optind;
+	}
+	return (optopt);			/* return option letter */
+}
diff --git a/contrib/unifdef/INSTALL b/contrib/unifdef/INSTALL
new file mode 100644
index 000000000000..03d7488588ab
--- /dev/null
+++ b/contrib/unifdef/INSTALL
@@ -0,0 +1,36 @@
+unifdef installation instructions
+---------------------------------
+
+Dependencies:
+ * unifdef is mostly ANSI C, with a few unixisms
+ * unifdefall is a Unix shell script
+ * the manual uses the nroff mdoc macros
+ * the support and test scripts are Unix shell scripts
+
+To build on Unix, type `make`. You can adjust the compilation options
+using the POSIX standard CFLAGS and LDFLAGS make variables.
+
+To install in your home directory, type `make install`
+or to install in /usr type `make prefix=/usr install`.
+See the start of the Makefile for the install location
+variables.
+
+The win32 subdirectory contains build files for MinGW and Visual
+Studio 2010 which make use of the FreeBSD code plus some other
+portability wrappers.
+
+To build with MinGW, type `mingw32-make -f win32/Makefile.mingw`.
+
+Unlike the Unix Makefile, the Windows builds do not automatically
+create or update version.h. The release tar and zip files include a
+pre-generated version.h but the git repository does not. To build from
+a git clone you need a Unix shell environment, which you can get as
+part of GitHub for Windows - http://windows.github.com/
+To update version.h, right-click on the fanf2/unifdef repository and
+select "open a shell here", then type `sh scripts\reversion.sh`.
+
+We assume Unix provides the BSD err.h functions and C99 stdbool.h. The
+FreeBSD subdirectory has copies of err.c and getopt.c for systems such
+as Windows that don't have them built in.
+
+- end -
diff --git a/contrib/unifdef/Makefile b/contrib/unifdef/Makefile
new file mode 100644
index 000000000000..36c70283c1b7
--- /dev/null
+++ b/contrib/unifdef/Makefile
@@ -0,0 +1,58 @@
+# Makefile for unifdef
+
+prefix =	${HOME}
+bindir =	${prefix}/bin
+mandir =	${prefix}/share/man
+man1dir=	${mandir}/man1
+
+bindest=	${DESTDIR}${bindir}
+man1dest=	${DESTDIR}${man1dir}
+
+all: unifdef
+
+unifdef: unifdef.c unifdef.h version.h
+	${CC} ${CFLAGS} ${LDFLAGS} -o unifdef unifdef.c
+
+version.h: version.sh
+version.sh::
+	scripts/reversion.sh
+
+test: unifdef
+	scripts/runtests.sh tests
+
+install: unifdef unifdefall.sh unifdef.1
+	: commands
+	install -m 755 -d  ${bindest}
+	install -m 755 unifdef  ${bindest}/
+	install -m 755 unifdefall.sh  ${bindest}/unifdefall
+	: manual
+	install -m 755 -d  ${man1dest}
+	install -m 644 unifdef.1  ${man1dest}/
+	ln -s unifdef.1  ${man1dest}/unifdefall.1
+
+clean:
+	rm -f unifdef version.h
+	rm -f tests/*.out tests/*.err tests/*.rc
+
+realclean: clean
+	rm -f unifdef.txt
+	[ ! -d .git ] || rm -f Changelog version.sh
+	find . -name .git -prune -o \( \
+		-name '*~' -o -name '.#*' -o \
+		-name '*.orig' -o -name '*.core' -o \
+		-name 'xterm-*' -o -name 'xterm.tar.gz' \
+		\) -delete
+
+DISTEXTRA= version.h version.sh unifdef.txt Changelog
+
+release: ${DISTEXTRA}
+	scripts/copycheck.sh
+	scripts/release.sh ${DISTEXTRA}
+
+unifdef.txt: unifdef.1
+	nroff -Tascii -mdoc unifdef.1 | col -bx >unifdef.txt
+
+Changelog: version.sh scripts/gitlog2changelog.sh
+	scripts/gitlog2changelog.sh >Changelog
+
+# eof
diff --git a/contrib/unifdef/README b/contrib/unifdef/README
new file mode 100644
index 000000000000..cdf52e1e0c62
--- /dev/null
+++ b/contrib/unifdef/README
@@ -0,0 +1,53 @@
+unifdef - selectively remove C preprocessor conditionals
+
+Written by Tony Finch <dot@dotat.at> - http://dotat.at/prog/unifdef/
+
+The unifdef utility selectively processes conditional C preprocessor
+#if and #ifdef directives. It removes from a file both the directives
+and the additional text that they delimit, while otherwise leaving the
+file alone.
+
+Please see the INSTALL file for installation instructions.
+
+Pre-formatted documentation can be found in unifdef.txt
+
+You can download the latest release tar and zip files from:
+	http://dotat.at/prog/unifdef
+
+You can clone the development repository using:
+	git clone http://dotat.at/git/unifdef.git
+
+I also maintain a copy at http://github.com/fanf2/unifdef
+(Warning: GitHub's zip download is incomplete and unusable.)
+
+Please send bug reports and patches to me via email to the
+address above. Unless you state otherwise, I will assume that
+any contributions are under the two-clause BSD licence. See
+the COPYING file for details.
+
+Thanks to the following people for their contributions:
+
+Bob Proulx <bob@proulx.com>
+ - test suite
+
+Jonathan Nieder <jrnieder@gmail.com>
+ - bug fixes, improved unifdefall
+
+Anders H Kaseorg <andersk@mit.edu>
+ - bug fixes and other improvements
+
+Ruediger Meier <ruediger.meier@ga-group.nl>
+ - build and portability cleanups
+
+Ben Hutchings at Solarflare Communications
+ - lenient evaluation of && and ||
+
+Steve Underwood <steveu@coppice.org>
+ - read #define and #undef directives from a file
+
+Brian Ginsbach <ginsbach@netbsd.org>
+ - improved expression evaluator
+
+Other contributions are listed in the Changelog.
+
+- end -
diff --git a/contrib/unifdef/ifdef-how.pl b/contrib/unifdef/ifdef-how.pl
new file mode 100755
index 000000000000..f8b487512c2c
--- /dev/null
+++ b/contrib/unifdef/ifdef-how.pl
@@ -0,0 +1,42 @@
+#!/usr/bin/perl
+
+use warnings;
+use strict;
+
+if (@ARGV != 2) {
+	die <<END;
+usage: ifdef-how <file> <line>
+
+Print the sequence of preprocessor conditionals which lead to the
+given line being retained after preprocessing. There is no output
+if the line is always retained. Conditionals that must be true are
+printed verbatim; conditionals that musy be false have their
+preprocessor keyword prefixed with NOT.
+
+Warning: this program does not parse comments or strings, so it will
+not handle tricky code correctly.
+END
+}
+
+my $file = shift;
+my $line = shift;
+
+open my $fh, '<', $file
+    or die "ifdef-how: open $file: $!\n";
+
+my @stack;
+while (<$fh>) {
+	last if $. == $line;
+	if (m{^\s*#\s*(if|ifdef|ifndef)\b}) {
+		push @stack, $_;
+	}
+	if (m{^\s*#\s*(elif|else)\b}) {
+		$stack[-1] =~ s{^(\s*#\s*)(?!NOT)\b}{${1}NOT}gm;
+		$stack[-1] .= $_;
+	}
+	if (m{^\s*#\s*endif\b}) {
+		pop @stack;
+	}
+}
+
+print @stack;
diff --git a/contrib/unifdef/scripts/authors.svn b/contrib/unifdef/scripts/authors.svn
new file mode 100644
index 000000000000..7df117e2d355
--- /dev/null
+++ b/contrib/unifdef/scripts/authors.svn
@@ -0,0 +1,15 @@
+charnier = Philippe Charnier <charnier@FreeBSD.org>
+dd       = Dima Dorfman <dd@FreeBSD.org>
+ed       = Ed Schouten <ed@FreeBSD.org>
+fanf     = Tony Finch <fanf@FreeBSD.org>
+hrs      = Hiroki Sato <hrs@FreeBSD.org>
+imp      = Warner Losh <imp@FreeBSD.org>
+jmallett = Juli Mallett <jmallett@FreeBSD.org>
+joel     = Joel Dahl <joel@FreeBSD.org>
+markm    = Mark Murray <markm@FreeBSD.org>
+nik      = Nik Clayton <nik@FreeBSD.org>
+obrien   = David E. O'Brien <obrien@FreeBSD.org>
+peter    = Peter Wemm <peter@FreeBSD.org>
+rgrimes  = Rodney W. Grimes <rgrimes@FreeBSD.org>
+ru       = Ruslan Ermilov <ru@FreeBSD.org>
+schweikh = Jens Schweikhardt <schweikh@FreeBSD.org>
diff --git a/contrib/unifdef/scripts/copycheck.sh b/contrib/unifdef/scripts/copycheck.sh
new file mode 100755
index 000000000000..c55cd1a22548
--- /dev/null
+++ b/contrib/unifdef/scripts/copycheck.sh
@@ -0,0 +1,21 @@
+#!/bin/sh
+
+me=$(git config user.name || echo WHO-AM-I)
+now=$(date +%Y)
+
+! git grep -l "Copyright .* $me" |
+grep -v 'tests/.*[.]exp[a-z]*' |
+( while read f
+  do git log --format="%ci $f" -1 -- $f
+  done;
+  git log --format="%ci COPYING" -1
+) |
+grep ^$now |
+while read d t z f
+do grep -H -m 1 "Copyright .* $me" $f
+done |
+grep -v $now
+
+grep ^[.]Dd unifdef.1 | grep -v "$(date +'%B [0-9]*, %Y')"
+
+exit 0
diff --git a/contrib/unifdef/scripts/fixtests.sh b/contrib/unifdef/scripts/fixtests.sh
new file mode 100755
index 000000000000..a4d6a33b1cf3
--- /dev/null
+++ b/contrib/unifdef/scripts/fixtests.sh
@@ -0,0 +1,9 @@
+#!/bin/sh
+
+for ext in err out rc
+do
+	for f in tests/*.$ext
+	do
+		mv $f ${f%.$ext}.exp$ext
+	done
+done
diff --git a/contrib/unifdef/scripts/git.config b/contrib/unifdef/scripts/git.config
new file mode 100644
index 000000000000..557c2200ba41
--- /dev/null
+++ b/contrib/unifdef/scripts/git.config
@@ -0,0 +1,10 @@
+[core]
+	repositoryformatversion = 0
+[svn-remote "svn"]
+	rewriteRoot = svn://svn.FreeBSD.org/base/head/usr.bin/unifdef
+	url = svn+ssh://fanf@svn.FreeBSD.org/base/head/usr.bin/unifdef
+	fetch = :refs/remotes/git-svn
+[remote "github"]
+        url = git@github.com:fanf2/unifdef.git
+        fetch = +refs/heads/*:refs/remotes/github/*
+        fetch = +refs/pull/*/head:refs/remotes/github/pull/*
diff --git a/contrib/unifdef/scripts/gitlog2changelog.sh b/contrib/unifdef/scripts/gitlog2changelog.sh
new file mode 100755
index 000000000000..52130237e72a
--- /dev/null
+++ b/contrib/unifdef/scripts/gitlog2changelog.sh
@@ -0,0 +1,9 @@
+#!/bin/sh
+
+line="---------------------------------------------------"
+
+git log --no-merges -M --stat \
+    --pretty=format:"$line%n%ai %an <%ae>%n%n%s%n%n%b" |
+uniq | fold -s
+echo
+echo $line
diff --git a/contrib/unifdef/scripts/release.sh b/contrib/unifdef/scripts/release.sh
new file mode 100755
index 000000000000..bfdd4fc3a1e7
--- /dev/null
+++ b/contrib/unifdef/scripts/release.sh
@@ -0,0 +1,18 @@
+#!/bin/sh
+
+. ./version.sh
+
+for f in $@ $(git ls-files | egrep -v '^web/|^[.]git$')
+do
+	mkdir -p web/$V/$(dirname $f)
+	cp $f web/$V/$f
+done
+
+cd web
+zip -qr $V.zip $V
+tar cf $V.tar $V
+xz -k9 $V.tar
+gzip -9 $V.tar
+rm -R $V
+
+ls -l $V.*
diff --git a/contrib/unifdef/scripts/reversion.sh b/contrib/unifdef/scripts/reversion.sh
new file mode 100755
index 000000000000..5098d8ad5c6f
--- /dev/null
+++ b/contrib/unifdef/scripts/reversion.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+if [ ! -f version.sh ] && [ ! -d .git ]
+then
+	echo Your copy of unifdef is incomplete 1>&2
+	exit 1
+fi
+
+[ -f version.sh ] && . ./version.sh
+
+if [ -d .git ]
+then
+	GV=$(git describe | sed 's|-g*|.|g;s|[.]|-|')
+	git update-index -q --refresh
+	if git diff-index --quiet HEAD
+	then
+		GD="$(git show --pretty=format:%ai -s HEAD)"
+	else
+		GD="$(date +'%Y-%m-%d %H:%M:%S %z')"
+		GV=$GV.XX
+	fi
+	[ unifdef -nt unifdef.c ] &&
+	[ unifdef -nt unifdef.h ] &&
+		GD="$D"
+	if [ "$GV $GD" != "$V $D" ]
+	then
+		echo "version $V $D"   1>&2
+		echo "     -> $GV $GD" 1>&2
+		V="$GV"
+		D="$GD"
+		echo "V=\"$V\""  >version.sh
+		echo "D=\"$D\"" >>version.sh
+		rm -f version.h
+	fi
+fi
+
+if [ ! -f version.h ]
+then
+	printf '"@(#) $Version: %s $\\n"\n' "$V" >version.h
+	printf '"@(#) $Date: %s $\\n"\n'   "$D" >>version.h
+fi
diff --git a/contrib/unifdef/scripts/runtests.sh b/contrib/unifdef/scripts/runtests.sh
new file mode 100755
index 000000000000..452f0e9e06e1
--- /dev/null
+++ b/contrib/unifdef/scripts/runtests.sh
@@ -0,0 +1,38 @@
+#!/bin/sh
+
+export PATH="$(pwd):${PATH}"
+${1:+cd} ${1:-:}
+for cmd in *.sh
+do
+	printf .
+	t=${cmd%.sh}
+
+	sh ./${cmd} >${t}.out 2>${t}.err
+	echo $? >${t}.rc
+
+	# strip carriage returns from error output
+	# in case we are trying to run on MinGW
+	tr -d '
' >${t}.xerr <${t}.err
+	mv ${t}.xerr ${t}.err
+
+	ok=true
+	for e in out err rc
+	do
+		exp=${t}.exp${e}
+		got=${t}.${e}
+		if ! cmp -s ${exp} ${got}
+		then
+			echo
+			echo FAILED: ${got}: $(cat ${cmd})
+			diff -u ${exp} ${got}
+			ok=false
+		fi
+	done
+
+	if ${ok}
+	then rm -f ${t}.out ${t}.err ${t}.rc
+	else rc=1
+	fi
+done
+echo
+exit ${rc}
diff --git a/contrib/unifdef/scripts/svnup.sh b/contrib/unifdef/scripts/svnup.sh
new file mode 100755
index 000000000000..51702df18633
--- /dev/null
+++ b/contrib/unifdef/scripts/svnup.sh
@@ -0,0 +1,12 @@
+#!/bin/sh -e
+
+git svn fetch -A scripts/authors.svn
+
+git checkout FreeBSD
+
+case "$(git merge --no-commit git-svn)" in
+"Already up-to-date.")
+	exit 0
+esac
+
+git commit -m 'Merge back from svn'
diff --git a/contrib/unifdef/scripts/upload.sh b/contrib/unifdef/scripts/upload.sh
new file mode 100755
index 000000000000..b55616d03f02
--- /dev/null
+++ b/contrib/unifdef/scripts/upload.sh
@@ -0,0 +1,19 @@
+#!/bin/sh -e
+
+make unifdef.txt
+cp unifdef.txt web
+
+git gc --aggressive
+git update-server-info
+git push --all github
+git push --tags github
+
+# for gitweb
+echo "selectively remove C preprocessor conditionals" >.git/description
+echo "Homepage: <a href='http://dotat.at/prog/unifdef'>http://dotat.at/prog/unifdef</a>" >.git/README.html
+
+touch .git/git-daemon-export-ok
+rsync --recursive --links --delete .git/ chiark:public-git/unifdef.git/
+rsync --recursive --links           web/ chiark:public-html/prog/unifdef/
+
+exit
diff --git a/contrib/unifdef/tests/000-init.experr b/contrib/unifdef/tests/000-init.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/000-init.expout b/contrib/unifdef/tests/000-init.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/000-init.exprc b/contrib/unifdef/tests/000-init.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/000-init.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/000-init.sh b/contrib/unifdef/tests/000-init.sh
new file mode 100644
index 000000000000..174f5c4a84a6
--- /dev/null
+++ b/contrib/unifdef/tests/000-init.sh
@@ -0,0 +1 @@
+unifdef </dev/null >/dev/null 2>&1 || true
diff --git a/contrib/unifdef/tests/NetBSD-42628.c b/contrib/unifdef/tests/NetBSD-42628.c
new file mode 100644
index 000000000000..9de6a94a0773
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-42628.c
@@ -0,0 +1,25 @@
+#if defined(__FreeBSD__)
+#include <netinet/if_fddi.h>
+#else
+#include <net/if_fddi.h>
+#endif
+
+#if defined(__FreeBSD__)
+	#include <stdbool.h>
+		#include <stdbool.h>
+			#include <stdbool.h>
+			#include <stdbool.h>
+		#include <stdbool.h>
+	#include <stdbool.h>
+#else
+#include <stdint.h>
+#endif
+
+#if defined(__FreeBSD__)
+#endif
+
+#ifdef __FreeBSD__
+#include <unistd.h>
+#else
+#include <inttypes.h>
+#endif
diff --git a/contrib/unifdef/tests/NetBSD-42628.experr b/contrib/unifdef/tests/NetBSD-42628.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/NetBSD-42628.expout b/contrib/unifdef/tests/NetBSD-42628.expout
new file mode 100644
index 000000000000..2d52e9e7ae29
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-42628.expout
@@ -0,0 +1,6 @@
+#include <net/if_fddi.h>
+
+#include <stdint.h>
+
+
+#include <inttypes.h>
diff --git a/contrib/unifdef/tests/NetBSD-42628.exprc b/contrib/unifdef/tests/NetBSD-42628.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-42628.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/NetBSD-42628.sh b/contrib/unifdef/tests/NetBSD-42628.sh
new file mode 100644
index 000000000000..87ac1aa9c4e8
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-42628.sh
@@ -0,0 +1 @@
+unifdef -U__FreeBSD__ NetBSD-42628.c
diff --git a/contrib/unifdef/tests/NetBSD-47068.c b/contrib/unifdef/tests/NetBSD-47068.c
new file mode 100644
index 000000000000..515f50b6eafd
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-47068.c
@@ -0,0 +1,2 @@
+#ifdef foo
+#endif
\ No newline at end of file
diff --git a/contrib/unifdef/tests/NetBSD-47068.experr b/contrib/unifdef/tests/NetBSD-47068.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/NetBSD-47068.expout b/contrib/unifdef/tests/NetBSD-47068.expout
new file mode 100644
index 000000000000..1fb9d525074e
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-47068.expout
@@ -0,0 +1,2 @@
+#ifdef foo
+#endif
diff --git a/contrib/unifdef/tests/NetBSD-47068.exprc b/contrib/unifdef/tests/NetBSD-47068.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-47068.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/NetBSD-47068.sh b/contrib/unifdef/tests/NetBSD-47068.sh
new file mode 100644
index 000000000000..2ec1bbef00a1
--- /dev/null
+++ b/contrib/unifdef/tests/NetBSD-47068.sh
@@ -0,0 +1 @@
+unifdef -Ubar NetBSD-47068.c
diff --git a/contrib/unifdef/tests/args1.c b/contrib/unifdef/tests/args1.c
new file mode 100644
index 000000000000..1cb554688c37
--- /dev/null
+++ b/contrib/unifdef/tests/args1.c
@@ -0,0 +1,3 @@
+#if defined(DUMMY) || FOO(arg)
+hello
+#endif
diff --git a/contrib/unifdef/tests/args1.experr b/contrib/unifdef/tests/args1.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/args1.expout b/contrib/unifdef/tests/args1.expout
new file mode 100644
index 000000000000..ce013625030b
--- /dev/null
+++ b/contrib/unifdef/tests/args1.expout
@@ -0,0 +1 @@
+hello
diff --git a/contrib/unifdef/tests/args1.exprc b/contrib/unifdef/tests/args1.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/args1.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/args1.sh b/contrib/unifdef/tests/args1.sh
new file mode 100644
index 000000000000..051baf41118a
--- /dev/null
+++ b/contrib/unifdef/tests/args1.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR args1.c
diff --git a/contrib/unifdef/tests/args2.c b/contrib/unifdef/tests/args2.c
new file mode 100644
index 000000000000..8fe476b18ee2
--- /dev/null
+++ b/contrib/unifdef/tests/args2.c
@@ -0,0 +1,3 @@
+#if defined(FOO) || BAR(arg)
+hello
+#endif
diff --git a/contrib/unifdef/tests/args2.experr b/contrib/unifdef/tests/args2.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/args2.expout b/contrib/unifdef/tests/args2.expout
new file mode 100644
index 000000000000..8fe476b18ee2
--- /dev/null
+++ b/contrib/unifdef/tests/args2.expout
@@ -0,0 +1,3 @@
+#if defined(FOO) || BAR(arg)
+hello
+#endif
diff --git a/contrib/unifdef/tests/args2.exprc b/contrib/unifdef/tests/args2.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/args2.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/args2.sh b/contrib/unifdef/tests/args2.sh
new file mode 100644
index 000000000000..19fb26136b0b
--- /dev/null
+++ b/contrib/unifdef/tests/args2.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR args2.c
diff --git a/contrib/unifdef/tests/blank0d.c b/contrib/unifdef/tests/blank0d.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank0d.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank0d.experr b/contrib/unifdef/tests/blank0d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank0d.expout b/contrib/unifdef/tests/blank0d.expout
new file mode 100644
index 000000000000..9c2261485ba5
--- /dev/null
+++ b/contrib/unifdef/tests/blank0d.expout
@@ -0,0 +1,23 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+zero
diff --git a/contrib/unifdef/tests/blank0d.exprc b/contrib/unifdef/tests/blank0d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank0d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank0d.sh b/contrib/unifdef/tests/blank0d.sh
new file mode 100644
index 000000000000..f0af220989d1
--- /dev/null
+++ b/contrib/unifdef/tests/blank0d.sh
@@ -0,0 +1 @@
+unifdef -B -DFOO0 blank0d.c
diff --git a/contrib/unifdef/tests/blank0u.c b/contrib/unifdef/tests/blank0u.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank0u.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank0u.experr b/contrib/unifdef/tests/blank0u.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank0u.expout b/contrib/unifdef/tests/blank0u.expout
new file mode 100644
index 000000000000..165d0a903525
--- /dev/null
+++ b/contrib/unifdef/tests/blank0u.expout
@@ -0,0 +1,22 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
diff --git a/contrib/unifdef/tests/blank0u.exprc b/contrib/unifdef/tests/blank0u.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank0u.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank0u.sh b/contrib/unifdef/tests/blank0u.sh
new file mode 100644
index 000000000000..22a8360282c2
--- /dev/null
+++ b/contrib/unifdef/tests/blank0u.sh
@@ -0,0 +1 @@
+unifdef -B -UFOO0 blank0u.c
diff --git a/contrib/unifdef/tests/blank1d.c b/contrib/unifdef/tests/blank1d.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank1d.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank1d.experr b/contrib/unifdef/tests/blank1d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank1d.expout b/contrib/unifdef/tests/blank1d.expout
new file mode 100644
index 000000000000..05f6bc538b88
--- /dev/null
+++ b/contrib/unifdef/tests/blank1d.expout
@@ -0,0 +1,23 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+one
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank1d.exprc b/contrib/unifdef/tests/blank1d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank1d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank1d.sh b/contrib/unifdef/tests/blank1d.sh
new file mode 100644
index 000000000000..4820efd723b9
--- /dev/null
+++ b/contrib/unifdef/tests/blank1d.sh
@@ -0,0 +1 @@
+unifdef -B -DFOO1 blank1d.c
diff --git a/contrib/unifdef/tests/blank1u.c b/contrib/unifdef/tests/blank1u.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank1u.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank1u.experr b/contrib/unifdef/tests/blank1u.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank1u.expout b/contrib/unifdef/tests/blank1u.expout
new file mode 100644
index 000000000000..f79337918e0e
--- /dev/null
+++ b/contrib/unifdef/tests/blank1u.expout
@@ -0,0 +1,21 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank1u.exprc b/contrib/unifdef/tests/blank1u.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank1u.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank1u.sh b/contrib/unifdef/tests/blank1u.sh
new file mode 100644
index 000000000000..1dbd849b018f
--- /dev/null
+++ b/contrib/unifdef/tests/blank1u.sh
@@ -0,0 +1 @@
+unifdef -B -UFOO1 blank1u.c
diff --git a/contrib/unifdef/tests/blank2d.c b/contrib/unifdef/tests/blank2d.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank2d.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank2d.experr b/contrib/unifdef/tests/blank2d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank2d.expout b/contrib/unifdef/tests/blank2d.expout
new file mode 100644
index 000000000000..ba127f52e4f1
--- /dev/null
+++ b/contrib/unifdef/tests/blank2d.expout
@@ -0,0 +1,23 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+two
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank2d.exprc b/contrib/unifdef/tests/blank2d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank2d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank2d.sh b/contrib/unifdef/tests/blank2d.sh
new file mode 100644
index 000000000000..a38cb0cee808
--- /dev/null
+++ b/contrib/unifdef/tests/blank2d.sh
@@ -0,0 +1 @@
+unifdef -B -DFOO2 blank2d.c
diff --git a/contrib/unifdef/tests/blank2u.c b/contrib/unifdef/tests/blank2u.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank2u.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank2u.experr b/contrib/unifdef/tests/blank2u.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank2u.expout b/contrib/unifdef/tests/blank2u.expout
new file mode 100644
index 000000000000..cee6dd72eb9a
--- /dev/null
+++ b/contrib/unifdef/tests/blank2u.expout
@@ -0,0 +1,20 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank2u.exprc b/contrib/unifdef/tests/blank2u.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank2u.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank2u.sh b/contrib/unifdef/tests/blank2u.sh
new file mode 100644
index 000000000000..70b5440fe28c
--- /dev/null
+++ b/contrib/unifdef/tests/blank2u.sh
@@ -0,0 +1 @@
+unifdef -B -UFOO2 blank2u.c
diff --git a/contrib/unifdef/tests/blank3d.c b/contrib/unifdef/tests/blank3d.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank3d.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank3d.experr b/contrib/unifdef/tests/blank3d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank3d.expout b/contrib/unifdef/tests/blank3d.expout
new file mode 100644
index 000000000000..31a633a0ea57
--- /dev/null
+++ b/contrib/unifdef/tests/blank3d.expout
@@ -0,0 +1,23 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+three
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank3d.exprc b/contrib/unifdef/tests/blank3d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank3d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank3d.sh b/contrib/unifdef/tests/blank3d.sh
new file mode 100644
index 000000000000..8e71cbec759f
--- /dev/null
+++ b/contrib/unifdef/tests/blank3d.sh
@@ -0,0 +1 @@
+unifdef -B -DFOO3 blank3d.c
diff --git a/contrib/unifdef/tests/blank3u.c b/contrib/unifdef/tests/blank3u.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank3u.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank3u.experr b/contrib/unifdef/tests/blank3u.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank3u.expout b/contrib/unifdef/tests/blank3u.expout
new file mode 100644
index 000000000000..d90cca9c6168
--- /dev/null
+++ b/contrib/unifdef/tests/blank3u.expout
@@ -0,0 +1,19 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank3u.exprc b/contrib/unifdef/tests/blank3u.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank3u.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank3u.sh b/contrib/unifdef/tests/blank3u.sh
new file mode 100644
index 000000000000..c1e8f20d2bc8
--- /dev/null
+++ b/contrib/unifdef/tests/blank3u.sh
@@ -0,0 +1 @@
+unifdef -B -UFOO3 blank3u.c
diff --git a/contrib/unifdef/tests/blank4d.c b/contrib/unifdef/tests/blank4d.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank4d.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank4d.experr b/contrib/unifdef/tests/blank4d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank4d.expout b/contrib/unifdef/tests/blank4d.expout
new file mode 100644
index 000000000000..782ff9d74faf
--- /dev/null
+++ b/contrib/unifdef/tests/blank4d.expout
@@ -0,0 +1,23 @@
+four
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank4d.exprc b/contrib/unifdef/tests/blank4d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank4d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank4d.sh b/contrib/unifdef/tests/blank4d.sh
new file mode 100644
index 000000000000..9471b63f06f5
--- /dev/null
+++ b/contrib/unifdef/tests/blank4d.sh
@@ -0,0 +1 @@
+unifdef -B -DFOO4 blank4d.c
diff --git a/contrib/unifdef/tests/blank4u.c b/contrib/unifdef/tests/blank4u.c
new file mode 100644
index 000000000000..c435ac5b6224
--- /dev/null
+++ b/contrib/unifdef/tests/blank4u.c
@@ -0,0 +1,25 @@
+#ifdef FOO4
+four
+#endif
+
+
+
+
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank4u.experr b/contrib/unifdef/tests/blank4u.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/blank4u.expout b/contrib/unifdef/tests/blank4u.expout
new file mode 100644
index 000000000000..72f0fa7987fd
--- /dev/null
+++ b/contrib/unifdef/tests/blank4u.expout
@@ -0,0 +1,18 @@
+#ifdef FOO3
+three
+#endif
+
+
+
+#ifdef FOO2
+two
+#endif
+
+
+#ifdef FOO1
+one
+#endif
+
+#ifdef FOO0
+zero
+#endif
diff --git a/contrib/unifdef/tests/blank4u.exprc b/contrib/unifdef/tests/blank4u.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/blank4u.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/blank4u.sh b/contrib/unifdef/tests/blank4u.sh
new file mode 100644
index 000000000000..16065df4669f
--- /dev/null
+++ b/contrib/unifdef/tests/blank4u.sh
@@ -0,0 +1 @@
+unifdef -B -UFOO4 blank4u.c
diff --git a/contrib/unifdef/tests/broken2.h b/contrib/unifdef/tests/broken2.h
new file mode 100644
index 000000000000..4221f04abf3b
--- /dev/null
+++ b/contrib/unifdef/tests/broken2.h
@@ -0,0 +1 @@
+#define    /* nothing */
diff --git a/contrib/unifdef/tests/broken3.h b/contrib/unifdef/tests/broken3.h
new file mode 100644
index 000000000000..c7c82c1bd8bf
--- /dev/null
+++ b/contrib/unifdef/tests/broken3.h
@@ -0,0 +1 @@
+#undef &%^$&%$##@^$
diff --git a/contrib/unifdef/tests/broken4.h b/contrib/unifdef/tests/broken4.h
new file mode 100644
index 000000000000..138cf65b583a
--- /dev/null
+++ b/contrib/unifdef/tests/broken4.h
@@ -0,0 +1,2 @@
+#define FOO \
+        bar
diff --git a/contrib/unifdef/tests/crlf-a.experr b/contrib/unifdef/tests/crlf-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/crlf-a.expout b/contrib/unifdef/tests/crlf-a.expout
new file mode 100644
index 000000000000..29e1b63ab239
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-a.expout
@@ -0,0 +1,10 @@
+int f1() { return 0; }
+\/
+/\
+comment
+/\
+*\
+comment
+*\
+/\
+eof
diff --git a/contrib/unifdef/tests/crlf-a.exprc b/contrib/unifdef/tests/crlf-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/crlf-a.sh b/contrib/unifdef/tests/crlf-a.sh
new file mode 100644
index 000000000000..2acc2bfa0488
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-a.sh
@@ -0,0 +1 @@
+unifdef -DF1 crlf.c
diff --git a/contrib/unifdef/tests/crlf-b.experr b/contrib/unifdef/tests/crlf-b.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/crlf-b.expout b/contrib/unifdef/tests/crlf-b.expout
new file mode 100644
index 000000000000..011b81a6cedd
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-b.expout
@@ -0,0 +1,14 @@
+#if F1
+int f1() { return 0; }
+#else
+int f2() { return 0; }
+#endif
+\/
+/\
+comment
+/\
+*\
+comment
+*\
+/\
+eof
diff --git a/contrib/unifdef/tests/crlf-b.exprc b/contrib/unifdef/tests/crlf-b.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-b.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/crlf-b.sh b/contrib/unifdef/tests/crlf-b.sh
new file mode 100644
index 000000000000..57d9de5f7c34
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-b.sh
@@ -0,0 +1 @@
+unifdef -DF2 crlf.c
diff --git a/contrib/unifdef/tests/crlf-c.experr b/contrib/unifdef/tests/crlf-c.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/crlf-c.expout b/contrib/unifdef/tests/crlf-c.expout
new file mode 100644
index 000000000000..f9fdaf832c7f
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-c.expout
@@ -0,0 +1,16 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#else
+int f3() { return 0; }
+#endif
+\/
+/\
+comment
+/\
+*\
+comment
+*\
+/\
+eof
diff --git a/contrib/unifdef/tests/crlf-c.exprc b/contrib/unifdef/tests/crlf-c.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-c.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/crlf-c.sh b/contrib/unifdef/tests/crlf-c.sh
new file mode 100644
index 000000000000..ad6f131379bb
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-c.sh
@@ -0,0 +1 @@
+unifdef -DF3 crlf.c
diff --git a/contrib/unifdef/tests/crlf-d.experr b/contrib/unifdef/tests/crlf-d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/crlf-d.expout b/contrib/unifdef/tests/crlf-d.expout
new file mode 100644
index 000000000000..295d337d5c74
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-d.expout
@@ -0,0 +1,18 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#elif F3
+int f3() { return 0; }
+#else
+int f4() { return 0; }
+#endif
+\/
+/\
+comment
+/\
+*\
+comment
+*\
+/\
+eof
diff --git a/contrib/unifdef/tests/crlf-d.exprc b/contrib/unifdef/tests/crlf-d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/crlf-d.sh b/contrib/unifdef/tests/crlf-d.sh
new file mode 100644
index 000000000000..719c05b6df46
--- /dev/null
+++ b/contrib/unifdef/tests/crlf-d.sh
@@ -0,0 +1 @@
+unifdef -DF4 crlf.c
diff --git a/contrib/unifdef/tests/crlf.c b/contrib/unifdef/tests/crlf.c
new file mode 100644
index 000000000000..ad911dc63a32
--- /dev/null
+++ b/contrib/unifdef/tests/crlf.c
@@ -0,0 +1,20 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#elif F3
+int f3() { return 0; }
+#elif F4
+int f4() { return 0; }
+#else
+int f() { return 0; }
+#endif
+\/
+/\
+comment
+/\
+*\
+comment
+*\
+/\
+eof
diff --git a/contrib/unifdef/tests/dangle.c b/contrib/unifdef/tests/dangle.c
new file mode 100644
index 000000000000..370a976dbd14
--- /dev/null
+++ b/contrib/unifdef/tests/dangle.c
@@ -0,0 +1,6 @@
+#ifdef FIRST
+wombats
+#endif /* com
+          mmm
+          mmmm
+          ment */
diff --git a/contrib/unifdef/tests/dangle.experr b/contrib/unifdef/tests/dangle.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/dangle.expout b/contrib/unifdef/tests/dangle.expout
new file mode 100644
index 000000000000..370a976dbd14
--- /dev/null
+++ b/contrib/unifdef/tests/dangle.expout
@@ -0,0 +1,6 @@
+#ifdef FIRST
+wombats
+#endif /* com
+          mmm
+          mmmm
+          ment */
diff --git a/contrib/unifdef/tests/dangle.exprc b/contrib/unifdef/tests/dangle.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/dangle.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/dangle.sh b/contrib/unifdef/tests/dangle.sh
new file mode 100644
index 000000000000..0520ac5bb372
--- /dev/null
+++ b/contrib/unifdef/tests/dangle.sh
@@ -0,0 +1 @@
+unifdef dangle.c
diff --git a/contrib/unifdef/tests/debian-603860.c b/contrib/unifdef/tests/debian-603860.c
new file mode 100644
index 000000000000..ae40ce1809c1
--- /dev/null
+++ b/contrib/unifdef/tests/debian-603860.c
@@ -0,0 +1,8 @@
+#ifdef FOO
+int a;
+#endif
+char foo[] = "rm -rf /*";
+#ifdef FOO
+int b;
+#endif
+/* baz */
diff --git a/contrib/unifdef/tests/debian-603860.experr b/contrib/unifdef/tests/debian-603860.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/debian-603860.expout b/contrib/unifdef/tests/debian-603860.expout
new file mode 100644
index 000000000000..e04772cc230b
--- /dev/null
+++ b/contrib/unifdef/tests/debian-603860.expout
@@ -0,0 +1,2 @@
+char foo[] = "rm -rf /*";
+/* baz */
diff --git a/contrib/unifdef/tests/debian-603860.exprc b/contrib/unifdef/tests/debian-603860.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/debian-603860.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/debian-603860.sh b/contrib/unifdef/tests/debian-603860.sh
new file mode 100644
index 000000000000..b77ae9cc10e3
--- /dev/null
+++ b/contrib/unifdef/tests/debian-603860.sh
@@ -0,0 +1 @@
+unifdef -UFOO debian-603860.c
diff --git a/contrib/unifdef/tests/defundef-broken2.experr b/contrib/unifdef/tests/defundef-broken2.experr
new file mode 100644
index 000000000000..fdfd6e237c23
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken2.experr
@@ -0,0 +1,2 @@
+unifdef: broken2.h: 1: Missing macro name in #define
+unifdef: Output may be truncated
diff --git a/contrib/unifdef/tests/defundef-broken2.expout b/contrib/unifdef/tests/defundef-broken2.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/defundef-broken2.exprc b/contrib/unifdef/tests/defundef-broken2.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken2.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/defundef-broken2.sh b/contrib/unifdef/tests/defundef-broken2.sh
new file mode 100644
index 000000000000..16c7384d8cdd
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken2.sh
@@ -0,0 +1 @@
+unifdef -f broken2.h if1.c
diff --git a/contrib/unifdef/tests/defundef-broken3.experr b/contrib/unifdef/tests/defundef-broken3.experr
new file mode 100644
index 000000000000..0b0b63a4b71c
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken3.experr
@@ -0,0 +1,2 @@
+unifdef: broken3.h: 1: Missing macro name in #undef
+unifdef: Output may be truncated
diff --git a/contrib/unifdef/tests/defundef-broken3.expout b/contrib/unifdef/tests/defundef-broken3.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/defundef-broken3.exprc b/contrib/unifdef/tests/defundef-broken3.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken3.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/defundef-broken3.sh b/contrib/unifdef/tests/defundef-broken3.sh
new file mode 100644
index 000000000000..123e725715dd
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken3.sh
@@ -0,0 +1 @@
+unifdef -f broken3.h if1.c
diff --git a/contrib/unifdef/tests/defundef-broken4.experr b/contrib/unifdef/tests/defundef-broken4.experr
new file mode 100644
index 000000000000..65c0ad5ad240
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken4.experr
@@ -0,0 +1,2 @@
+unifdef: broken4.h: 1: Obfuscated preprocessor control line
+unifdef: Output may be truncated
diff --git a/contrib/unifdef/tests/defundef-broken4.expout b/contrib/unifdef/tests/defundef-broken4.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/defundef-broken4.exprc b/contrib/unifdef/tests/defundef-broken4.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken4.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/defundef-broken4.sh b/contrib/unifdef/tests/defundef-broken4.sh
new file mode 100644
index 000000000000..1c85536f7c58
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-broken4.sh
@@ -0,0 +1 @@
+unifdef -f broken4.h if1.c
diff --git a/contrib/unifdef/tests/defundef-funlike.experr b/contrib/unifdef/tests/defundef-funlike.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/defundef-funlike.expout b/contrib/unifdef/tests/defundef-funlike.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-funlike.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/defundef-funlike.exprc b/contrib/unifdef/tests/defundef-funlike.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-funlike.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/defundef-funlike.sh b/contrib/unifdef/tests/defundef-funlike.sh
new file mode 100644
index 000000000000..91c91af4cd0b
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-funlike.sh
@@ -0,0 +1 @@
+unifdef -f funlike.h small1.c
diff --git a/contrib/unifdef/tests/defundef-undefdef.experr b/contrib/unifdef/tests/defundef-undefdef.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/defundef-undefdef.expout b/contrib/unifdef/tests/defundef-undefdef.expout
new file mode 100644
index 000000000000..c51d7a6bec42
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-undefdef.expout
@@ -0,0 +1 @@
+int f1() { return 0; }
diff --git a/contrib/unifdef/tests/defundef-undefdef.exprc b/contrib/unifdef/tests/defundef-undefdef.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-undefdef.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/defundef-undefdef.sh b/contrib/unifdef/tests/defundef-undefdef.sh
new file mode 100644
index 000000000000..4af30c7f1eba
--- /dev/null
+++ b/contrib/unifdef/tests/defundef-undefdef.sh
@@ -0,0 +1 @@
+unifdef -f if6.h if6.c
diff --git a/contrib/unifdef/tests/div.c b/contrib/unifdef/tests/div.c
new file mode 100644
index 000000000000..f825bec5effd
--- /dev/null
+++ b/contrib/unifdef/tests/div.c
@@ -0,0 +1,3 @@
+#if 10 / DENOM
+DIVISION
+#endif
diff --git a/contrib/unifdef/tests/div.experr b/contrib/unifdef/tests/div.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/div.expout b/contrib/unifdef/tests/div.expout
new file mode 100644
index 000000000000..769481fd8910
--- /dev/null
+++ b/contrib/unifdef/tests/div.expout
@@ -0,0 +1,10 @@
+undef
+#if 10 / DENOM
+DIVISION
+#endif
+one
+DIVISION
+zero
+#if 10 / DENOM
+DIVISION
+#endif
diff --git a/contrib/unifdef/tests/div.exprc b/contrib/unifdef/tests/div.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/div.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/div.sh b/contrib/unifdef/tests/div.sh
new file mode 100644
index 000000000000..f526f9f1a1ca
--- /dev/null
+++ b/contrib/unifdef/tests/div.sh
@@ -0,0 +1,10 @@
+echo undef
+if ! unifdef div.c
+then unifdef -d div.c
+fi
+echo one
+unifdef -DDENOM div.c
+echo zero
+if ! unifdef -UDENOM div.c
+then unifdef -d -UDENOM div.c
+fi
diff --git a/contrib/unifdef/tests/empty.c b/contrib/unifdef/tests/empty.c
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/empty.experr b/contrib/unifdef/tests/empty.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/empty.expout b/contrib/unifdef/tests/empty.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/empty.exprc b/contrib/unifdef/tests/empty.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/empty.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/empty.sh b/contrib/unifdef/tests/empty.sh
new file mode 100644
index 000000000000..c2dd1671d623
--- /dev/null
+++ b/contrib/unifdef/tests/empty.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR empty.c
diff --git a/contrib/unifdef/tests/error.c b/contrib/unifdef/tests/error.c
new file mode 100644
index 000000000000..7cd15e7d966a
--- /dev/null
+++ b/contrib/unifdef/tests/error.c
@@ -0,0 +1,4 @@
+#if FOO != 5
+#error
+#endif
+bar
diff --git a/contrib/unifdef/tests/error.experr b/contrib/unifdef/tests/error.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/error.expout b/contrib/unifdef/tests/error.expout
new file mode 100644
index 000000000000..274284345ca2
--- /dev/null
+++ b/contrib/unifdef/tests/error.expout
@@ -0,0 +1,2 @@
+#error
+bar
diff --git a/contrib/unifdef/tests/error.exprc b/contrib/unifdef/tests/error.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/error.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/error.sh b/contrib/unifdef/tests/error.sh
new file mode 100644
index 000000000000..1267f0f0d603
--- /dev/null
+++ b/contrib/unifdef/tests/error.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 error.c
diff --git a/contrib/unifdef/tests/exitmode0a.experr b/contrib/unifdef/tests/exitmode0a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode0a.expout b/contrib/unifdef/tests/exitmode0a.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0a.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode0a.exprc b/contrib/unifdef/tests/exitmode0a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/exitmode0a.sh b/contrib/unifdef/tests/exitmode0a.sh
new file mode 100644
index 000000000000..6c171732a6cf
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0a.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR -x0 if1.c
diff --git a/contrib/unifdef/tests/exitmode0b.experr b/contrib/unifdef/tests/exitmode0b.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode0b.expout b/contrib/unifdef/tests/exitmode0b.expout
new file mode 100644
index 000000000000..9e588c22791c
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0b.expout
@@ -0,0 +1,26 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode0b.exprc b/contrib/unifdef/tests/exitmode0b.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0b.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/exitmode0b.sh b/contrib/unifdef/tests/exitmode0b.sh
new file mode 100644
index 000000000000..339bb3e4149d
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode0b.sh
@@ -0,0 +1 @@
+unifdef -x0 if1.c
diff --git a/contrib/unifdef/tests/exitmode1a.experr b/contrib/unifdef/tests/exitmode1a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode1a.expout b/contrib/unifdef/tests/exitmode1a.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1a.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode1a.exprc b/contrib/unifdef/tests/exitmode1a.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1a.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/exitmode1a.sh b/contrib/unifdef/tests/exitmode1a.sh
new file mode 100644
index 000000000000..4d40a13f69db
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1a.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR -x1 if1.c
diff --git a/contrib/unifdef/tests/exitmode1b.experr b/contrib/unifdef/tests/exitmode1b.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode1b.expout b/contrib/unifdef/tests/exitmode1b.expout
new file mode 100644
index 000000000000..9e588c22791c
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1b.expout
@@ -0,0 +1,26 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode1b.exprc b/contrib/unifdef/tests/exitmode1b.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1b.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/exitmode1b.sh b/contrib/unifdef/tests/exitmode1b.sh
new file mode 100644
index 000000000000..19bf1c196660
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode1b.sh
@@ -0,0 +1 @@
+unifdef -x1 if1.c
diff --git a/contrib/unifdef/tests/exitmode2a.experr b/contrib/unifdef/tests/exitmode2a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode2a.expout b/contrib/unifdef/tests/exitmode2a.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2a.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode2a.exprc b/contrib/unifdef/tests/exitmode2a.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2a.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/exitmode2a.sh b/contrib/unifdef/tests/exitmode2a.sh
new file mode 100644
index 000000000000..42db886dc5da
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2a.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR -x2 if1.c
diff --git a/contrib/unifdef/tests/exitmode2b.experr b/contrib/unifdef/tests/exitmode2b.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitmode2b.expout b/contrib/unifdef/tests/exitmode2b.expout
new file mode 100644
index 000000000000..9e588c22791c
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2b.expout
@@ -0,0 +1,26 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/exitmode2b.exprc b/contrib/unifdef/tests/exitmode2b.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2b.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/exitmode2b.sh b/contrib/unifdef/tests/exitmode2b.sh
new file mode 100644
index 000000000000..30bdd3ba33b9
--- /dev/null
+++ b/contrib/unifdef/tests/exitmode2b.sh
@@ -0,0 +1 @@
+unifdef -x2 if1.c
diff --git a/contrib/unifdef/tests/exitstat.c b/contrib/unifdef/tests/exitstat.c
new file mode 100644
index 000000000000..5413a07a46fc
--- /dev/null
+++ b/contrib/unifdef/tests/exitstat.c
@@ -0,0 +1,3 @@
+#if FALSE
+#elif TRUE
+#endif
diff --git a/contrib/unifdef/tests/exitstat.experr b/contrib/unifdef/tests/exitstat.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/exitstat.expout b/contrib/unifdef/tests/exitstat.expout
new file mode 100644
index 000000000000..e08e8fb49178
--- /dev/null
+++ b/contrib/unifdef/tests/exitstat.expout
@@ -0,0 +1,3 @@
+#if FALSE
+#else
+#endif
diff --git a/contrib/unifdef/tests/exitstat.exprc b/contrib/unifdef/tests/exitstat.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/exitstat.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/exitstat.sh b/contrib/unifdef/tests/exitstat.sh
new file mode 100644
index 000000000000..df0060f73638
--- /dev/null
+++ b/contrib/unifdef/tests/exitstat.sh
@@ -0,0 +1 @@
+unifdef -DTRUE=1 exitstat.c
diff --git a/contrib/unifdef/tests/funlike.h b/contrib/unifdef/tests/funlike.h
new file mode 100644
index 000000000000..5e657946e36b
--- /dev/null
+++ b/contrib/unifdef/tests/funlike.h
@@ -0,0 +1 @@
+#define FOO(a,b,c) a+b+c
diff --git a/contrib/unifdef/tests/if1-a.experr b/contrib/unifdef/tests/if1-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1-a.expout b/contrib/unifdef/tests/if1-a.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/if1-a.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-a.exprc b/contrib/unifdef/tests/if1-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1-a.sh b/contrib/unifdef/tests/if1-a.sh
new file mode 100644
index 000000000000..57b7cd5b7a56
--- /dev/null
+++ b/contrib/unifdef/tests/if1-a.sh
@@ -0,0 +1 @@
+unifdefall.sh -DFOO=1 -DFOOB=42 -UBAR if1.c
diff --git a/contrib/unifdef/tests/if1-f.experr b/contrib/unifdef/tests/if1-f.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1-f.expout b/contrib/unifdef/tests/if1-f.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/if1-f.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-f.exprc b/contrib/unifdef/tests/if1-f.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1-f.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1-f.sh b/contrib/unifdef/tests/if1-f.sh
new file mode 100644
index 000000000000..4a9698c08d3c
--- /dev/null
+++ b/contrib/unifdef/tests/if1-f.sh
@@ -0,0 +1 @@
+unifdef -f if1.h if1.c
diff --git a/contrib/unifdef/tests/if1-k.c b/contrib/unifdef/tests/if1-k.c
new file mode 100644
index 000000000000..712350f9c13c
--- /dev/null
+++ b/contrib/unifdef/tests/if1-k.c
@@ -0,0 +1,38 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is commented out. "#if 1 else" */
+#endif
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-k.experr b/contrib/unifdef/tests/if1-k.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1-k.expout b/contrib/unifdef/tests/if1-k.expout
new file mode 100644
index 000000000000..2be8567b970c
--- /dev/null
+++ b/contrib/unifdef/tests/if1-k.expout
@@ -0,0 +1,30 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-k.exprc b/contrib/unifdef/tests/if1-k.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1-k.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1-k.sh b/contrib/unifdef/tests/if1-k.sh
new file mode 100644
index 000000000000..dc33e1afbda0
--- /dev/null
+++ b/contrib/unifdef/tests/if1-k.sh
@@ -0,0 +1 @@
+unifdef -k if1-k.c
diff --git a/contrib/unifdef/tests/if1-kDU.c b/contrib/unifdef/tests/if1-kDU.c
new file mode 100644
index 000000000000..712350f9c13c
--- /dev/null
+++ b/contrib/unifdef/tests/if1-kDU.c
@@ -0,0 +1,38 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is commented out. "#if 1 else" */
+#endif
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-kDU.experr b/contrib/unifdef/tests/if1-kDU.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1-kDU.expout b/contrib/unifdef/tests/if1-kDU.expout
new file mode 100644
index 000000000000..c308e43b5a09
--- /dev/null
+++ b/contrib/unifdef/tests/if1-kDU.expout
@@ -0,0 +1,20 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1-kDU.exprc b/contrib/unifdef/tests/if1-kDU.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1-kDU.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1-kDU.sh b/contrib/unifdef/tests/if1-kDU.sh
new file mode 100644
index 000000000000..49231b7a4d9a
--- /dev/null
+++ b/contrib/unifdef/tests/if1-kDU.sh
@@ -0,0 +1 @@
+unifdef -k -DFOO=1 -DFOOB=42 -UBAR if1-kDU.c
diff --git a/contrib/unifdef/tests/if1.c b/contrib/unifdef/tests/if1.c
new file mode 100644
index 000000000000..9e588c22791c
--- /dev/null
+++ b/contrib/unifdef/tests/if1.c
@@ -0,0 +1,26 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1.experr b/contrib/unifdef/tests/if1.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1.expout b/contrib/unifdef/tests/if1.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/if1.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1.exprc b/contrib/unifdef/tests/if1.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1.h b/contrib/unifdef/tests/if1.h
new file mode 100644
index 000000000000..3441c1bd8b85
--- /dev/null
+++ b/contrib/unifdef/tests/if1.h
@@ -0,0 +1,3 @@
+#define FOO 1
+#define FOOB 42
+#undef BAR
diff --git a/contrib/unifdef/tests/if1.sh b/contrib/unifdef/tests/if1.sh
new file mode 100644
index 000000000000..36a1cef8285a
--- /dev/null
+++ b/contrib/unifdef/tests/if1.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if1.c
diff --git a/contrib/unifdef/tests/if1a.experr b/contrib/unifdef/tests/if1a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if1a.expout b/contrib/unifdef/tests/if1a.expout
new file mode 100644
index 000000000000..956eea0b20b2
--- /dev/null
+++ b/contrib/unifdef/tests/if1a.expout
@@ -0,0 +1,24 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if   FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/if1a.exprc b/contrib/unifdef/tests/if1a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if1a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if1a.sh b/contrib/unifdef/tests/if1a.sh
new file mode 100644
index 000000000000..ac54227c7502
--- /dev/null
+++ b/contrib/unifdef/tests/if1a.sh
@@ -0,0 +1 @@
+unifdef -UBAR if1.c
diff --git a/contrib/unifdef/tests/if2-a.experr b/contrib/unifdef/tests/if2-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if2-a.expout b/contrib/unifdef/tests/if2-a.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/if2-a.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2-a.exprc b/contrib/unifdef/tests/if2-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if2-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if2-a.sh b/contrib/unifdef/tests/if2-a.sh
new file mode 100644
index 000000000000..acefce8f833c
--- /dev/null
+++ b/contrib/unifdef/tests/if2-a.sh
@@ -0,0 +1 @@
+unifdefall.sh -DFOO=1 -DFOOB=42 -UBAR if2.c
diff --git a/contrib/unifdef/tests/if2-k.c b/contrib/unifdef/tests/if2-k.c
new file mode 100644
index 000000000000..b5a9109d6ff9
--- /dev/null
+++ b/contrib/unifdef/tests/if2-k.c
@@ -0,0 +1,29 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if defined(FOO)
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2-k.experr b/contrib/unifdef/tests/if2-k.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if2-k.expout b/contrib/unifdef/tests/if2-k.expout
new file mode 100644
index 000000000000..6a173a4e0a3b
--- /dev/null
+++ b/contrib/unifdef/tests/if2-k.expout
@@ -0,0 +1,21 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+#if defined(FOO)
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2-k.exprc b/contrib/unifdef/tests/if2-k.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if2-k.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if2-k.sh b/contrib/unifdef/tests/if2-k.sh
new file mode 100644
index 000000000000..5875af3227cd
--- /dev/null
+++ b/contrib/unifdef/tests/if2-k.sh
@@ -0,0 +1 @@
+unifdef -k if2-k.c
diff --git a/contrib/unifdef/tests/if2-kDU.c b/contrib/unifdef/tests/if2-kDU.c
new file mode 100644
index 000000000000..b5a9109d6ff9
--- /dev/null
+++ b/contrib/unifdef/tests/if2-kDU.c
@@ -0,0 +1,29 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if defined(FOO)
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2-kDU.experr b/contrib/unifdef/tests/if2-kDU.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if2-kDU.expout b/contrib/unifdef/tests/if2-kDU.expout
new file mode 100644
index 000000000000..7cf0ddc9c796
--- /dev/null
+++ b/contrib/unifdef/tests/if2-kDU.expout
@@ -0,0 +1,17 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2-kDU.exprc b/contrib/unifdef/tests/if2-kDU.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if2-kDU.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if2-kDU.sh b/contrib/unifdef/tests/if2-kDU.sh
new file mode 100644
index 000000000000..567ca0af4ac9
--- /dev/null
+++ b/contrib/unifdef/tests/if2-kDU.sh
@@ -0,0 +1 @@
+unifdef -k -DFOO=1 -DFOOB=42 -UBAR if2-kDU.c
diff --git a/contrib/unifdef/tests/if2.c b/contrib/unifdef/tests/if2.c
new file mode 100644
index 000000000000..44fdae070f3e
--- /dev/null
+++ b/contrib/unifdef/tests/if2.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(FOO)
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2.experr b/contrib/unifdef/tests/if2.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if2.expout b/contrib/unifdef/tests/if2.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/if2.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if2.exprc b/contrib/unifdef/tests/if2.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if2.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if2.sh b/contrib/unifdef/tests/if2.sh
new file mode 100644
index 000000000000..e10159a1f9f5
--- /dev/null
+++ b/contrib/unifdef/tests/if2.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if2.c
diff --git a/contrib/unifdef/tests/if3-a.experr b/contrib/unifdef/tests/if3-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if3-a.expout b/contrib/unifdef/tests/if3-a.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/if3-a.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3-a.exprc b/contrib/unifdef/tests/if3-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if3-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if3-a.sh b/contrib/unifdef/tests/if3-a.sh
new file mode 100644
index 000000000000..f6b1500a2d2c
--- /dev/null
+++ b/contrib/unifdef/tests/if3-a.sh
@@ -0,0 +1 @@
+unifdefall.sh -DFOO=1 -DFOOB=42 -UBAR if3.c
diff --git a/contrib/unifdef/tests/if3-k.c b/contrib/unifdef/tests/if3-k.c
new file mode 100644
index 000000000000..c90102155f4d
--- /dev/null
+++ b/contrib/unifdef/tests/if3-k.c
@@ -0,0 +1,29 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if ! defined(BAR)
+int foo() { return 0; }
+#else
+#error BAR defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3-k.experr b/contrib/unifdef/tests/if3-k.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if3-k.expout b/contrib/unifdef/tests/if3-k.expout
new file mode 100644
index 000000000000..e0e23867de64
--- /dev/null
+++ b/contrib/unifdef/tests/if3-k.expout
@@ -0,0 +1,21 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+#if ! defined(BAR)
+int foo() { return 0; }
+#else
+#error BAR defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3-k.exprc b/contrib/unifdef/tests/if3-k.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if3-k.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if3-k.sh b/contrib/unifdef/tests/if3-k.sh
new file mode 100644
index 000000000000..4bd48da7c5b7
--- /dev/null
+++ b/contrib/unifdef/tests/if3-k.sh
@@ -0,0 +1 @@
+unifdef -k if3-k.c
diff --git a/contrib/unifdef/tests/if3-kDU.c b/contrib/unifdef/tests/if3-kDU.c
new file mode 100644
index 000000000000..c90102155f4d
--- /dev/null
+++ b/contrib/unifdef/tests/if3-kDU.c
@@ -0,0 +1,29 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if ! defined(BAR)
+int foo() { return 0; }
+#else
+#error BAR defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3-kDU.experr b/contrib/unifdef/tests/if3-kDU.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if3-kDU.expout b/contrib/unifdef/tests/if3-kDU.expout
new file mode 100644
index 000000000000..7cf0ddc9c796
--- /dev/null
+++ b/contrib/unifdef/tests/if3-kDU.expout
@@ -0,0 +1,17 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3-kDU.exprc b/contrib/unifdef/tests/if3-kDU.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if3-kDU.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if3-kDU.sh b/contrib/unifdef/tests/if3-kDU.sh
new file mode 100644
index 000000000000..795e54f25c5f
--- /dev/null
+++ b/contrib/unifdef/tests/if3-kDU.sh
@@ -0,0 +1 @@
+unifdef -k -DFOO=1 -DFOOB=42 -UBAR if3-kDU.c
diff --git a/contrib/unifdef/tests/if3.c b/contrib/unifdef/tests/if3.c
new file mode 100644
index 000000000000..2a87102fab5a
--- /dev/null
+++ b/contrib/unifdef/tests/if3.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if ! defined(BAR)
+int foo() { return 0; }
+#else
+#error BAR defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3.experr b/contrib/unifdef/tests/if3.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if3.expout b/contrib/unifdef/tests/if3.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/if3.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/if3.exprc b/contrib/unifdef/tests/if3.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if3.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if3.sh b/contrib/unifdef/tests/if3.sh
new file mode 100644
index 000000000000..9345010283ff
--- /dev/null
+++ b/contrib/unifdef/tests/if3.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if3.c
diff --git a/contrib/unifdef/tests/if4-a.experr b/contrib/unifdef/tests/if4-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if4-a.expout b/contrib/unifdef/tests/if4-a.expout
new file mode 100644
index 000000000000..55dfe32d1272
--- /dev/null
+++ b/contrib/unifdef/tests/if4-a.expout
@@ -0,0 +1,22 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4-a.exprc b/contrib/unifdef/tests/if4-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if4-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if4-a.sh b/contrib/unifdef/tests/if4-a.sh
new file mode 100644
index 000000000000..888f9014f0a5
--- /dev/null
+++ b/contrib/unifdef/tests/if4-a.sh
@@ -0,0 +1 @@
+unifdefall.sh -DFOO=1 -DFOOB=42 -UBAR if4.c
diff --git a/contrib/unifdef/tests/if4-k.c b/contrib/unifdef/tests/if4-k.c
new file mode 100644
index 000000000000..b31bca49c443
--- /dev/null
+++ b/contrib/unifdef/tests/if4-k.c
@@ -0,0 +1,50 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if defined(FOO) || defined(FOOB)
+int foo1() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOOB) || defined(FOO)
+int foo2() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOO) && defined(FOOB)
+int foo3() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+#if defined(FOOB) && defined(FOO)
+int foo4() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4-k.experr b/contrib/unifdef/tests/if4-k.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if4-k.expout b/contrib/unifdef/tests/if4-k.expout
new file mode 100644
index 000000000000..bb94d6a14e64
--- /dev/null
+++ b/contrib/unifdef/tests/if4-k.expout
@@ -0,0 +1,42 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+#if defined(FOO) || defined(FOOB)
+int foo1() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOOB) || defined(FOO)
+int foo2() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOO) && defined(FOOB)
+int foo3() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+#if defined(FOOB) && defined(FOO)
+int foo4() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4-k.exprc b/contrib/unifdef/tests/if4-k.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if4-k.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if4-k.sh b/contrib/unifdef/tests/if4-k.sh
new file mode 100644
index 000000000000..277d248a1328
--- /dev/null
+++ b/contrib/unifdef/tests/if4-k.sh
@@ -0,0 +1 @@
+unifdef -k if4-k.c
diff --git a/contrib/unifdef/tests/if4-kDU.c b/contrib/unifdef/tests/if4-kDU.c
new file mode 100644
index 000000000000..b31bca49c443
--- /dev/null
+++ b/contrib/unifdef/tests/if4-kDU.c
@@ -0,0 +1,50 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if defined(FOO) || defined(FOOB)
+int foo1() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOOB) || defined(FOO)
+int foo2() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOO) && defined(FOOB)
+int foo3() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+#if defined(FOOB) && defined(FOO)
+int foo4() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4-kDU.experr b/contrib/unifdef/tests/if4-kDU.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if4-kDU.expout b/contrib/unifdef/tests/if4-kDU.expout
new file mode 100644
index 000000000000..919bd63a8eda
--- /dev/null
+++ b/contrib/unifdef/tests/if4-kDU.expout
@@ -0,0 +1,26 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4-kDU.exprc b/contrib/unifdef/tests/if4-kDU.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if4-kDU.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if4-kDU.sh b/contrib/unifdef/tests/if4-kDU.sh
new file mode 100644
index 000000000000..57c3e93d1c8b
--- /dev/null
+++ b/contrib/unifdef/tests/if4-kDU.sh
@@ -0,0 +1 @@
+unifdef -k -DFOO=1 -DFOOB=42 -UBAR if4-kDU.c
diff --git a/contrib/unifdef/tests/if4.c b/contrib/unifdef/tests/if4.c
new file mode 100644
index 000000000000..a8be34883d02
--- /dev/null
+++ b/contrib/unifdef/tests/if4.c
@@ -0,0 +1,38 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(FOO) || defined(FOOB)
+int foo1() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOOB) || defined(FOO)
+int foo2() { return 0; }
+#else
+#error FOO or FOOB not defined
+#endif
+
+#if defined(FOO) && defined(FOOB)
+int foo3() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+#if defined(FOOB) && defined(FOO)
+int foo4() { return 0; }
+#else
+#error FOO and FOOB not defined
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4.experr b/contrib/unifdef/tests/if4.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if4.expout b/contrib/unifdef/tests/if4.expout
new file mode 100644
index 000000000000..55dfe32d1272
--- /dev/null
+++ b/contrib/unifdef/tests/if4.expout
@@ -0,0 +1,22 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+}
diff --git a/contrib/unifdef/tests/if4.exprc b/contrib/unifdef/tests/if4.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if4.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if4.sh b/contrib/unifdef/tests/if4.sh
new file mode 100644
index 000000000000..efbdbcfacc33
--- /dev/null
+++ b/contrib/unifdef/tests/if4.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if4.c
diff --git a/contrib/unifdef/tests/if5-a.experr b/contrib/unifdef/tests/if5-a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if5-a.expout b/contrib/unifdef/tests/if5-a.expout
new file mode 100644
index 000000000000..ffacc5e5a97f
--- /dev/null
+++ b/contrib/unifdef/tests/if5-a.expout
@@ -0,0 +1,40 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int foo5() { return 0; }
+
+int foo6() { return 0; }
+
+int foo7() { return 0; }
+
+int foo8() { return 0; }
+
+int foo9() { return 0; }
+
+int foo10() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+  foo7();
+  foo8();
+  foo9();
+  foo10();
+}
diff --git a/contrib/unifdef/tests/if5-a.exprc b/contrib/unifdef/tests/if5-a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if5-a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if5-a.sh b/contrib/unifdef/tests/if5-a.sh
new file mode 100644
index 000000000000..6c30b1f6d8cc
--- /dev/null
+++ b/contrib/unifdef/tests/if5-a.sh
@@ -0,0 +1 @@
+unifdefall.sh -DFOO=1 -DFOOB=42 -UBAR if5.c
diff --git a/contrib/unifdef/tests/if5-k.c b/contrib/unifdef/tests/if5-k.c
new file mode 100644
index 000000000000..2be184790ce8
--- /dev/null
+++ b/contrib/unifdef/tests/if5-k.c
@@ -0,0 +1,64 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if FOOB == 42
+int foo1() { return 0; }
+#else
+#error FOOB not 42
+#endif
+
+#if FOOB != 42
+#error FOO is 2
+#else
+int foo2() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO == 1
+intx foo3() { return 0; }
+#else
+#error FOO not 1 or BAR not 1
+#endif
+
+#if FOOB != 42 && FOO != 1
+#error FOOB not 42 and FOO not 1
+#else
+int foo4() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO != 1
+int foo5() { return 0; }
+#else
+#error FOOB is 42 or FOO is not 1
+#endif
+
+#if FOO != 1 || FOOB != 42
+#error FOO is 1 or FOOB is 42
+#else
+int foo6() { return 0; }
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+}
diff --git a/contrib/unifdef/tests/if5-k.experr b/contrib/unifdef/tests/if5-k.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if5-k.expout b/contrib/unifdef/tests/if5-k.expout
new file mode 100644
index 000000000000..4ae22c63d84a
--- /dev/null
+++ b/contrib/unifdef/tests/if5-k.expout
@@ -0,0 +1,56 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+#if FOOB == 42
+int foo1() { return 0; }
+#else
+#error FOOB not 42
+#endif
+
+#if FOOB != 42
+#error FOO is 2
+#else
+int foo2() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO == 1
+intx foo3() { return 0; }
+#else
+#error FOO not 1 or BAR not 1
+#endif
+
+#if FOOB != 42 && FOO != 1
+#error FOOB not 42 and FOO not 1
+#else
+int foo4() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO != 1
+int foo5() { return 0; }
+#else
+#error FOOB is 42 or FOO is not 1
+#endif
+
+#if FOO != 1 || FOOB != 42
+#error FOO is 1 or FOOB is 42
+#else
+int foo6() { return 0; }
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+}
diff --git a/contrib/unifdef/tests/if5-k.exprc b/contrib/unifdef/tests/if5-k.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if5-k.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if5-k.sh b/contrib/unifdef/tests/if5-k.sh
new file mode 100644
index 000000000000..01d92be152b3
--- /dev/null
+++ b/contrib/unifdef/tests/if5-k.sh
@@ -0,0 +1 @@
+unifdef -k if5-k.c
diff --git a/contrib/unifdef/tests/if5-kDU.c b/contrib/unifdef/tests/if5-kDU.c
new file mode 100644
index 000000000000..2be184790ce8
--- /dev/null
+++ b/contrib/unifdef/tests/if5-kDU.c
@@ -0,0 +1,64 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if 0
+/* This code is commented out. "#if 0 then" */
+#else
+/* This code is passed through. "#if 0 else" */
+#endif
+
+#if 1
+/* This code is passed through. "#if 1 then" */
+#else
+/* This code is passed through. "#if 1 else" */
+#endif
+
+#if FOOB == 42
+int foo1() { return 0; }
+#else
+#error FOOB not 42
+#endif
+
+#if FOOB != 42
+#error FOO is 2
+#else
+int foo2() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO == 1
+intx foo3() { return 0; }
+#else
+#error FOO not 1 or BAR not 1
+#endif
+
+#if FOOB != 42 && FOO != 1
+#error FOOB not 42 and FOO not 1
+#else
+int foo4() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO != 1
+int foo5() { return 0; }
+#else
+#error FOOB is 42 or FOO is not 1
+#endif
+
+#if FOO != 1 || FOOB != 42
+#error FOO is 1 or FOOB is 42
+#else
+int foo6() { return 0; }
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+}
diff --git a/contrib/unifdef/tests/if5-kDU.experr b/contrib/unifdef/tests/if5-kDU.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if5-kDU.expout b/contrib/unifdef/tests/if5-kDU.expout
new file mode 100644
index 000000000000..a8de2a19e987
--- /dev/null
+++ b/contrib/unifdef/tests/if5-kDU.expout
@@ -0,0 +1,32 @@
+/* Copyright 2004, 2008 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* This code is passed through. "#if 0 else" */
+
+/* This code is passed through. "#if 1 then" */
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+intx foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int foo5() { return 0; }
+
+int foo6() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+}
diff --git a/contrib/unifdef/tests/if5-kDU.exprc b/contrib/unifdef/tests/if5-kDU.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if5-kDU.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if5-kDU.sh b/contrib/unifdef/tests/if5-kDU.sh
new file mode 100644
index 000000000000..71f1677ee424
--- /dev/null
+++ b/contrib/unifdef/tests/if5-kDU.sh
@@ -0,0 +1 @@
+unifdef -k -DFOO=1 -DFOOB=42 -UBAR if5-kDU.c
diff --git a/contrib/unifdef/tests/if5.c b/contrib/unifdef/tests/if5.c
new file mode 100644
index 000000000000..5edba56817dc
--- /dev/null
+++ b/contrib/unifdef/tests/if5.c
@@ -0,0 +1,80 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOOB == 42
+int foo1() { return 0; }
+#else
+#error FOOB not 42
+#endif
+
+#if FOOB != 42
+#error FOO is 2
+#else
+int foo2() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO == 1
+int foo3() { return 0; }
+#else
+#error FOO not 1 or BAR not 1
+#endif
+
+#if FOOB != 42 && FOO != 1
+#error FOOB not 42 and FOO not 1
+#else
+int foo4() { return 0; }
+#endif
+
+#if FOOB == 42 || FOO != 1
+int foo5() { return 0; }
+#else
+#error FOOB is 42 or FOO is not 1
+#endif
+
+#if FOO != 1 || FOOB != 42
+#error FOO is 1 or FOOB is 42
+#else
+int foo6() { return 0; }
+#endif
+
+#if FOO > FOOB
+#error FOO is greater than FOOB
+#else
+int foo7() { return 0; }
+#endif
+
+#if FOOB < FOO
+#error FOOB is less than FOO
+#else
+int foo8() { return 0; }
+#endif
+
+#if FOO >= FOOB
+#error FOO is greater than or equal FOOB
+#else
+int foo9() { return 0; }
+#endif
+
+#if FOOB <= FOO
+#error FOOB is less than or equal FOO
+#else
+int foo10() { return 0; }
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+  foo7();
+  foo8();
+  foo9();
+  foo10();
+}
diff --git a/contrib/unifdef/tests/if5.experr b/contrib/unifdef/tests/if5.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if5.expout b/contrib/unifdef/tests/if5.expout
new file mode 100644
index 000000000000..ffacc5e5a97f
--- /dev/null
+++ b/contrib/unifdef/tests/if5.expout
@@ -0,0 +1,40 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int foo5() { return 0; }
+
+int foo6() { return 0; }
+
+int foo7() { return 0; }
+
+int foo8() { return 0; }
+
+int foo9() { return 0; }
+
+int foo10() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+  foo7();
+  foo8();
+  foo9();
+  foo10();
+}
diff --git a/contrib/unifdef/tests/if5.exprc b/contrib/unifdef/tests/if5.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if5.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if5.sh b/contrib/unifdef/tests/if5.sh
new file mode 100644
index 000000000000..e9417fbc800c
--- /dev/null
+++ b/contrib/unifdef/tests/if5.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if5.c
diff --git a/contrib/unifdef/tests/if6.c b/contrib/unifdef/tests/if6.c
new file mode 100644
index 000000000000..6abadb1106e2
--- /dev/null
+++ b/contrib/unifdef/tests/if6.c
@@ -0,0 +1,11 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#elif F3
+int f3() { return 0; }
+#elif F4
+int f4() { return 0; }
+#else
+int f() { return 0; }
+#endif
diff --git a/contrib/unifdef/tests/if6.h b/contrib/unifdef/tests/if6.h
new file mode 100644
index 000000000000..5c2faa2d6223
--- /dev/null
+++ b/contrib/unifdef/tests/if6.h
@@ -0,0 +1,2 @@
+#undef gruntfuttock
+#define F1 1
diff --git a/contrib/unifdef/tests/if6a.experr b/contrib/unifdef/tests/if6a.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if6a.expout b/contrib/unifdef/tests/if6a.expout
new file mode 100644
index 000000000000..c51d7a6bec42
--- /dev/null
+++ b/contrib/unifdef/tests/if6a.expout
@@ -0,0 +1 @@
+int f1() { return 0; }
diff --git a/contrib/unifdef/tests/if6a.exprc b/contrib/unifdef/tests/if6a.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if6a.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if6a.sh b/contrib/unifdef/tests/if6a.sh
new file mode 100644
index 000000000000..fec1e5f9ff27
--- /dev/null
+++ b/contrib/unifdef/tests/if6a.sh
@@ -0,0 +1 @@
+unifdef -DF1 if6.c
diff --git a/contrib/unifdef/tests/if6b.experr b/contrib/unifdef/tests/if6b.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if6b.expout b/contrib/unifdef/tests/if6b.expout
new file mode 100644
index 000000000000..0b7aa04243fb
--- /dev/null
+++ b/contrib/unifdef/tests/if6b.expout
@@ -0,0 +1,5 @@
+#if F1
+int f1() { return 0; }
+#else
+int f2() { return 0; }
+#endif
diff --git a/contrib/unifdef/tests/if6b.exprc b/contrib/unifdef/tests/if6b.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if6b.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if6b.sh b/contrib/unifdef/tests/if6b.sh
new file mode 100644
index 000000000000..bc46c0065c66
--- /dev/null
+++ b/contrib/unifdef/tests/if6b.sh
@@ -0,0 +1 @@
+unifdef -DF2 if6.c
diff --git a/contrib/unifdef/tests/if6c.experr b/contrib/unifdef/tests/if6c.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if6c.expout b/contrib/unifdef/tests/if6c.expout
new file mode 100644
index 000000000000..03341d93d850
--- /dev/null
+++ b/contrib/unifdef/tests/if6c.expout
@@ -0,0 +1,7 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#else
+int f3() { return 0; }
+#endif
diff --git a/contrib/unifdef/tests/if6c.exprc b/contrib/unifdef/tests/if6c.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if6c.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if6c.sh b/contrib/unifdef/tests/if6c.sh
new file mode 100644
index 000000000000..996a50dae773
--- /dev/null
+++ b/contrib/unifdef/tests/if6c.sh
@@ -0,0 +1 @@
+unifdef -DF3 if6.c
diff --git a/contrib/unifdef/tests/if6d.experr b/contrib/unifdef/tests/if6d.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if6d.expout b/contrib/unifdef/tests/if6d.expout
new file mode 100644
index 000000000000..76d70116976d
--- /dev/null
+++ b/contrib/unifdef/tests/if6d.expout
@@ -0,0 +1,9 @@
+#if F1
+int f1() { return 0; }
+#elif F2
+int f2() { return 0; }
+#elif F3
+int f3() { return 0; }
+#else
+int f4() { return 0; }
+#endif
diff --git a/contrib/unifdef/tests/if6d.exprc b/contrib/unifdef/tests/if6d.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if6d.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if6d.sh b/contrib/unifdef/tests/if6d.sh
new file mode 100644
index 000000000000..a9f180788cce
--- /dev/null
+++ b/contrib/unifdef/tests/if6d.sh
@@ -0,0 +1 @@
+unifdef -DF4 if6.c
diff --git a/contrib/unifdef/tests/if7.c b/contrib/unifdef/tests/if7.c
new file mode 100644
index 000000000000..1f86f8f598ea
--- /dev/null
+++ b/contrib/unifdef/tests/if7.c
@@ -0,0 +1,94 @@
+/*
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if (FOOB | FOO) == 43
+int foo1() { return 0; }
+#else
+#error FOOB bitwise-or FOO is not 43
+#endif
+
+#if (FOO ^ FOO) == 0
+int foo2() { return 0; }
+#else
+#error FOO bitwise-xor FOO is not 0
+#endif
+
+#if (FOOB & 2) == 2
+int foo3() { return 0; }
+#else
+#error FOOB bitwise-and 2 is not 2
+#endif
+
+#if (FOO << 1) == 2
+int foo4() { return 0; }
+#else
+#error FOO left-shift 2 is not 2
+#endif
+
+#if (FOOB >> 4) == 2
+int foo5() { return 0; }
+#else
+#error FOOB right-shift 2 is not 2
+#endif
+
+#if (FOOB + FOO) == 43
+int foo6() { return 0; }
+#else
+#error FOOB add FOO is not 43
+#endif
+
+#if (FOOB - FOO) == 41
+int foo7() { return 0; }
+#else
+#error FOOB subtract FOO is not 41
+#endif
+
+#if (FOOB * 2) == 84
+int foo8() { return 0; }
+#else
+#error FOOB multiply 2 is not 84
+#endif
+
+#if (FOOB / 2) == 21
+int foo9() { return 0; }
+#else
+#error FOOB divided 2 is not 21
+#endif
+
+#if (FOOB % FOO) == 0
+int foo10() { return 0; }
+#else
+#error FOOB modulo FOO is not 0
+#endif
+
+#if ~(FOOB) == -43
+int foo11() { return 0; }
+#else
+#error bitwise-not FOOB is not -43
+#endif
+
+#if -(FOOB) == -42
+int foo12() { return 0; }
+#else
+#error negate FOOB is not -42
+#endif
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+  foo7();
+  foo8();
+  foo9();
+  foo10();
+  foo11();
+  foo12();
+}
diff --git a/contrib/unifdef/tests/if7.experr b/contrib/unifdef/tests/if7.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/if7.expout b/contrib/unifdef/tests/if7.expout
new file mode 100644
index 000000000000..136a82a41bf6
--- /dev/null
+++ b/contrib/unifdef/tests/if7.expout
@@ -0,0 +1,46 @@
+/*
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo1() { return 0; }
+
+int foo2() { return 0; }
+
+int foo3() { return 0; }
+
+int foo4() { return 0; }
+
+int foo5() { return 0; }
+
+int foo6() { return 0; }
+
+int foo7() { return 0; }
+
+int foo8() { return 0; }
+
+int foo9() { return 0; }
+
+int foo10() { return 0; }
+
+int foo11() { return 0; }
+
+int foo12() { return 0; }
+
+int main()
+{
+  foo1();
+  foo2();
+  foo3();
+  foo4();
+  foo5();
+  foo6();
+  foo7();
+  foo8();
+  foo9();
+  foo10();
+  foo11();
+  foo12();
+}
diff --git a/contrib/unifdef/tests/if7.exprc b/contrib/unifdef/tests/if7.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/if7.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/if7.sh b/contrib/unifdef/tests/if7.sh
new file mode 100644
index 000000000000..107d5ed739ed
--- /dev/null
+++ b/contrib/unifdef/tests/if7.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR if7.c
diff --git a/contrib/unifdef/tests/indirect.experr b/contrib/unifdef/tests/indirect.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/indirect.expout b/contrib/unifdef/tests/indirect.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/indirect.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/indirect.exprc b/contrib/unifdef/tests/indirect.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/indirect.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/indirect.sh b/contrib/unifdef/tests/indirect.sh
new file mode 100644
index 000000000000..32fdee059b22
--- /dev/null
+++ b/contrib/unifdef/tests/indirect.sh
@@ -0,0 +1 @@
+unifdef -DFOO=ZIG -DZIG -DFOOB=42 -UBAR if1.c
diff --git a/contrib/unifdef/tests/multi-generic-sh b/contrib/unifdef/tests/multi-generic-sh
new file mode 100644
index 000000000000..80e568a72c30
--- /dev/null
+++ b/contrib/unifdef/tests/multi-generic-sh
@@ -0,0 +1,15 @@
+mfiles=""
+for f in $files
+do
+	rm -f m$f
+	[ -f $f ] && cp $f m$f
+	mfiles="$mfiles m$f"
+done
+unifdef -M~ $opts $mfiles
+e=$?
+for f in $mfiles
+do
+	diff -u $f~ $f | sed '/^[+-]\{3\} /s/	.*//'
+	rm -f $f~ $f
+done
+exit $e
diff --git a/contrib/unifdef/tests/multi.experr b/contrib/unifdef/tests/multi.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/multi.expout b/contrib/unifdef/tests/multi.expout
new file mode 100644
index 000000000000..c05227749e20
--- /dev/null
+++ b/contrib/unifdef/tests/multi.expout
@@ -0,0 +1,36 @@
+--- mif1.c~
++++ mif1.c
+@@ -5,19 +5,9 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if FOO
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+-#if BAR
+-int foo() { return 0; }
+-#elif FOO
+ int bar() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+ int main()
+ {
+--- mif2.c~
++++ mif2.c
+@@ -5,11 +5,7 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if defined(FOO)
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+ int main()
+ {
diff --git a/contrib/unifdef/tests/multi.exprc b/contrib/unifdef/tests/multi.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/multi.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/multi.sh b/contrib/unifdef/tests/multi.sh
new file mode 100644
index 000000000000..b0553ffea051
--- /dev/null
+++ b/contrib/unifdef/tests/multi.sh
@@ -0,0 +1,3 @@
+opts="-DFOO=1 -DFOOB=42 -UBAR"
+files="if1.c if2.c"
+. ./multi-generic-sh
diff --git a/contrib/unifdef/tests/multilnnum.experr b/contrib/unifdef/tests/multilnnum.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/multilnnum.expout b/contrib/unifdef/tests/multilnnum.expout
new file mode 100644
index 000000000000..628b359512f0
--- /dev/null
+++ b/contrib/unifdef/tests/multilnnum.expout
@@ -0,0 +1,42 @@
+--- mif1.c~
++++ mif1.c
+@@ -5,19 +5,13 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if FOO
++#line 9 "mif1.c"
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
++#line 13 "mif1.c"
+ 
+-#if BAR
+-int foo() { return 0; }
+-#elif FOO
++#line 17 "mif1.c"
+ int bar() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
++#line 21 "mif1.c"
+ 
+ int main()
+ {
+--- mif2.c~
++++ mif2.c
+@@ -5,11 +5,9 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if defined(FOO)
++#line 9 "mif2.c"
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
++#line 13 "mif2.c"
+ 
+ int main()
+ {
diff --git a/contrib/unifdef/tests/multilnnum.exprc b/contrib/unifdef/tests/multilnnum.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/multilnnum.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/multilnnum.sh b/contrib/unifdef/tests/multilnnum.sh
new file mode 100644
index 000000000000..df0953ebc2ef
--- /dev/null
+++ b/contrib/unifdef/tests/multilnnum.sh
@@ -0,0 +1,3 @@
+opts="-DFOO=1 -DFOOB=42 -UBAR -n"
+files="if1.c if2.c"
+. ./multi-generic-sh
diff --git a/contrib/unifdef/tests/multimissing.experr b/contrib/unifdef/tests/multimissing.experr
new file mode 100644
index 000000000000..d31b29f67d00
--- /dev/null
+++ b/contrib/unifdef/tests/multimissing.experr
@@ -0,0 +1,4 @@
+unifdef: can't open mifmissing.c: No such file or directory
+diff: mifmissing.c~: No such file or directory
+diff: mifmissing.c: No such file or directory
+diff: mif2.c~: No such file or directory
diff --git a/contrib/unifdef/tests/multimissing.expout b/contrib/unifdef/tests/multimissing.expout
new file mode 100644
index 000000000000..e130b731ac79
--- /dev/null
+++ b/contrib/unifdef/tests/multimissing.expout
@@ -0,0 +1,22 @@
+--- mif1.c~
++++ mif1.c
+@@ -5,19 +5,9 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if FOO
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+-#if BAR
+-int foo() { return 0; }
+-#elif FOO
+ int bar() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+ int main()
+ {
diff --git a/contrib/unifdef/tests/multimissing.exprc b/contrib/unifdef/tests/multimissing.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/multimissing.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/multimissing.sh b/contrib/unifdef/tests/multimissing.sh
new file mode 100644
index 000000000000..9c51147863b9
--- /dev/null
+++ b/contrib/unifdef/tests/multimissing.sh
@@ -0,0 +1,3 @@
+opts="-DFOO=1 -DFOOB=42 -UBAR"
+files="if1.c ifmissing.c if2.c"
+. ./multi-generic-sh
diff --git a/contrib/unifdef/tests/multinewline.experr b/contrib/unifdef/tests/multinewline.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/multinewline.expout b/contrib/unifdef/tests/multinewline.expout
new file mode 100644
index 000000000000..ff6118e57b6f
--- /dev/null
+++ b/contrib/unifdef/tests/multinewline.expout
@@ -0,0 +1,39 @@
+--- mcrlf.c~
++++ mcrlf.c
+@@ -1,14 +1,4 @@
+-#if F1
+ int f1() { return 0; }
+-#elif F2
+-int f2() { return 0; }
+-#elif F3
+-int f3() { return 0; }
+-#elif F4
+-int f4() { return 0; }
+-#else
+-int f() { return 0; }
+-#endif
+ \/
+ /\
+ comment
+--- mif1.c~
++++ mif1.c
+@@ -5,18 +5,12 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ 
+-#if FOO
+ int foo() { return 0; }
+-#else
+-#error FOO not defined
+-#endif
+ 
+ #if BAR
+ int foo() { return 0; }
+-#elif FOO
+-int bar() { return 0; }
+ #else
+-#error FOO not defined
++int bar() { return 0; }
+ #endif
+ 
+ int main()
diff --git a/contrib/unifdef/tests/multinewline.exprc b/contrib/unifdef/tests/multinewline.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/multinewline.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/multinewline.sh b/contrib/unifdef/tests/multinewline.sh
new file mode 100644
index 000000000000..19287a6340f6
--- /dev/null
+++ b/contrib/unifdef/tests/multinewline.sh
@@ -0,0 +1,3 @@
+opts="-DFOO -DF1"
+files="crlf.c if1.c"
+. ./multi-generic-sh
diff --git a/contrib/unifdef/tests/none.c b/contrib/unifdef/tests/none.c
new file mode 100644
index 000000000000..09d66b69ba9f
--- /dev/null
+++ b/contrib/unifdef/tests/none.c
@@ -0,0 +1,5 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+int foo() { return 0; }
diff --git a/contrib/unifdef/tests/none.experr b/contrib/unifdef/tests/none.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/none.expout b/contrib/unifdef/tests/none.expout
new file mode 100644
index 000000000000..09d66b69ba9f
--- /dev/null
+++ b/contrib/unifdef/tests/none.expout
@@ -0,0 +1,5 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+int foo() { return 0; }
diff --git a/contrib/unifdef/tests/none.exprc b/contrib/unifdef/tests/none.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/none.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/none.sh b/contrib/unifdef/tests/none.sh
new file mode 100644
index 000000000000..622f53b28434
--- /dev/null
+++ b/contrib/unifdef/tests/none.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR none.c
diff --git a/contrib/unifdef/tests/outdir.experr b/contrib/unifdef/tests/outdir.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/outdir.expout b/contrib/unifdef/tests/outdir.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/outdir.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/outdir.exprc b/contrib/unifdef/tests/outdir.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/outdir.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/outdir.sh b/contrib/unifdef/tests/outdir.sh
new file mode 100644
index 000000000000..c2de8547e646
--- /dev/null
+++ b/contrib/unifdef/tests/outdir.sh
@@ -0,0 +1,6 @@
+mkdir -p outdir
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooutdir/outfile.c if1.c
+e=$?
+cat outdir/outfile.c
+rm -r outdir
+exit $e
diff --git a/contrib/unifdef/tests/outeperm.experr b/contrib/unifdef/tests/outeperm.experr
new file mode 100644
index 000000000000..bed245174cf6
--- /dev/null
+++ b/contrib/unifdef/tests/outeperm.experr
@@ -0,0 +1 @@
+unifdef: can't create outdir/outfile.c: Permission denied
diff --git a/contrib/unifdef/tests/outeperm.expout b/contrib/unifdef/tests/outeperm.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/outeperm.exprc b/contrib/unifdef/tests/outeperm.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/outeperm.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/outeperm.sh b/contrib/unifdef/tests/outeperm.sh
new file mode 100644
index 000000000000..5f5abf0e41bd
--- /dev/null
+++ b/contrib/unifdef/tests/outeperm.sh
@@ -0,0 +1,6 @@
+mkdir -p outdir
+chmod 555 outdir
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooutdir/outfile.c if1.c
+e=$?
+rmdir outdir
+exit $e
diff --git a/contrib/unifdef/tests/outfile.experr b/contrib/unifdef/tests/outfile.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/outfile.expout b/contrib/unifdef/tests/outfile.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/outfile.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/outfile.exprc b/contrib/unifdef/tests/outfile.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/outfile.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/outfile.sh b/contrib/unifdef/tests/outfile.sh
new file mode 100644
index 000000000000..cdae73da9a44
--- /dev/null
+++ b/contrib/unifdef/tests/outfile.sh
@@ -0,0 +1,5 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooutfile.c if1.c
+e=$?
+cat outfile.c
+rm outfile.c
+exit $e
diff --git a/contrib/unifdef/tests/outperms.experr b/contrib/unifdef/tests/outperms.experr
new file mode 100644
index 000000000000..a2ef92c4c82d
--- /dev/null
+++ b/contrib/unifdef/tests/outperms.experr
@@ -0,0 +1 @@
+-rw-r-----
diff --git a/contrib/unifdef/tests/outperms.expout b/contrib/unifdef/tests/outperms.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/outperms.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/outperms.exprc b/contrib/unifdef/tests/outperms.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/outperms.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/outperms.sh b/contrib/unifdef/tests/outperms.sh
new file mode 100644
index 000000000000..2583bf5c076d
--- /dev/null
+++ b/contrib/unifdef/tests/outperms.sh
@@ -0,0 +1,10 @@
+umask 027
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooutfile.c if1.c
+e=$?
+case ${BUILD_MINGW} in
+(yes)	printf '%s\n' '-rw-r-----' 1>&2 ;;
+(*)	ls -l outfile.c | cut -d' ' -f1 1>&2 ;;
+esac
+cat outfile.c
+rm outfile.c
+exit $e
diff --git a/contrib/unifdef/tests/overdir.experr b/contrib/unifdef/tests/overdir.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overdir.expout b/contrib/unifdef/tests/overdir.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/overdir.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/overdir.exprc b/contrib/unifdef/tests/overdir.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/overdir.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/overdir.sh b/contrib/unifdef/tests/overdir.sh
new file mode 100644
index 000000000000..44124272f6f4
--- /dev/null
+++ b/contrib/unifdef/tests/overdir.sh
@@ -0,0 +1,7 @@
+mkdir -p overdir
+cp if1.c overdir/overwrite.c
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooverdir/overwrite.c overdir/overwrite.c
+e=$?
+cat overdir/overwrite.c
+rm -r overdir
+exit $e
diff --git a/contrib/unifdef/tests/overenoent.experr b/contrib/unifdef/tests/overenoent.experr
new file mode 100644
index 000000000000..f4e962f30651
--- /dev/null
+++ b/contrib/unifdef/tests/overenoent.experr
@@ -0,0 +1 @@
+unifdef: can't create outfile.c: No such file or directory
diff --git a/contrib/unifdef/tests/overenoent.expout b/contrib/unifdef/tests/overenoent.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overenoent.exprc b/contrib/unifdef/tests/overenoent.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/overenoent.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/overenoent.sh b/contrib/unifdef/tests/overenoent.sh
new file mode 100644
index 000000000000..9cbf2ab332ac
--- /dev/null
+++ b/contrib/unifdef/tests/overenoent.sh
@@ -0,0 +1,5 @@
+ln -s nonexistent/path outfile.c
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooutfile.c if1.c
+e=$?
+rm -f outfile.c
+exit $e
diff --git a/contrib/unifdef/tests/overin.experr b/contrib/unifdef/tests/overin.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overin.expout b/contrib/unifdef/tests/overin.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/overin.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/overin.exprc b/contrib/unifdef/tests/overin.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/overin.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/overin.sh b/contrib/unifdef/tests/overin.sh
new file mode 100644
index 000000000000..78eb75ab4b80
--- /dev/null
+++ b/contrib/unifdef/tests/overin.sh
@@ -0,0 +1,6 @@
+cp if1.c overin.c
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooverin.c <overin.c
+e=$?
+cat overin.c
+rm overin.c
+exit $e
diff --git a/contrib/unifdef/tests/overlnnum.experr b/contrib/unifdef/tests/overlnnum.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overlnnum.expout b/contrib/unifdef/tests/overlnnum.expout
new file mode 100644
index 000000000000..c3f5787a98c4
--- /dev/null
+++ b/contrib/unifdef/tests/overlnnum.expout
@@ -0,0 +1,20 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#line 9 "overwrite.c"
+int foo() { return 0; }
+#line 13 "overwrite.c"
+
+#line 17 "overwrite.c"
+int bar() { return 0; }
+#line 21 "overwrite.c"
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/overlnnum.exprc b/contrib/unifdef/tests/overlnnum.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/overlnnum.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/overlnnum.sh b/contrib/unifdef/tests/overlnnum.sh
new file mode 100644
index 000000000000..f6090bdc0018
--- /dev/null
+++ b/contrib/unifdef/tests/overlnnum.sh
@@ -0,0 +1,6 @@
+cp if1.c overwrite.c
+unifdef -DFOO=1 -DFOOB=42 -UBAR -n -ooverwrite.c overwrite.c
+e=$?
+cat overwrite.c
+rm overwrite.c
+exit $e
diff --git a/contrib/unifdef/tests/overperms.experr b/contrib/unifdef/tests/overperms.experr
new file mode 100644
index 000000000000..9fc8473109d5
--- /dev/null
+++ b/contrib/unifdef/tests/overperms.experr
@@ -0,0 +1,2 @@
+-rw-r-----
+-rw-r-----
diff --git a/contrib/unifdef/tests/overperms.expout b/contrib/unifdef/tests/overperms.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/overperms.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/overperms.exprc b/contrib/unifdef/tests/overperms.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/overperms.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/overperms.sh b/contrib/unifdef/tests/overperms.sh
new file mode 100644
index 000000000000..fa1559333c40
--- /dev/null
+++ b/contrib/unifdef/tests/overperms.sh
@@ -0,0 +1,12 @@
+cp if1.c outfile.c
+chmod 640 outfile.c
+ls -l outfile.c | cut -d' ' -f1 1>&2
+unifdef -DFOO=1 -DFOOB=42 -UBAR -m outfile.c
+e=$?
+case ${BUILD_MINGW} in
+(yes)	printf '%s\n' '-rw-r-----' 1>&2 ;;
+(*)	ls -l outfile.c | cut -d' ' -f1 1>&2 ;;
+esac
+cat outfile.c
+rm outfile.c
+exit $e
diff --git a/contrib/unifdef/tests/overunchanged.experr b/contrib/unifdef/tests/overunchanged.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overunchanged.expout b/contrib/unifdef/tests/overunchanged.expout
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overunchanged.exprc b/contrib/unifdef/tests/overunchanged.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/overunchanged.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/overunchanged.sh b/contrib/unifdef/tests/overunchanged.sh
new file mode 100644
index 000000000000..a4a4c790ee14
--- /dev/null
+++ b/contrib/unifdef/tests/overunchanged.sh
@@ -0,0 +1,8 @@
+cp if1.c overunchanged.c
+ls -i overunchanged.c >overunchanged-before
+unifdef -DWEASEL=1 -ooverunchanged.c overunchanged.c
+e=$?
+ls -i overunchanged.c >overunchanged-after
+diff overunchanged-before overunchanged-after
+rm -f overunchanged-before overunchanged-after overunchanged.c
+exit $e
diff --git a/contrib/unifdef/tests/overwrite.experr b/contrib/unifdef/tests/overwrite.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/overwrite.expout b/contrib/unifdef/tests/overwrite.expout
new file mode 100644
index 000000000000..56ae03cc38de
--- /dev/null
+++ b/contrib/unifdef/tests/overwrite.expout
@@ -0,0 +1,16 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int bar() { return 0; }
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/overwrite.exprc b/contrib/unifdef/tests/overwrite.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/overwrite.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/overwrite.sh b/contrib/unifdef/tests/overwrite.sh
new file mode 100644
index 000000000000..8d9a9c7d7ecf
--- /dev/null
+++ b/contrib/unifdef/tests/overwrite.sh
@@ -0,0 +1,6 @@
+cp if1.c overwrite.c
+unifdef -DFOO=1 -DFOOB=42 -UBAR -ooverwrite.c overwrite.c
+e=$?
+cat overwrite.c
+rm overwrite.c
+exit $e
diff --git a/contrib/unifdef/tests/recursive.experr b/contrib/unifdef/tests/recursive.experr
new file mode 100644
index 000000000000..bcb00f76d094
--- /dev/null
+++ b/contrib/unifdef/tests/recursive.experr
@@ -0,0 +1,120 @@
+unifdef: addsym FOO=BAR
+unifdef: addsym BAR=ZIG
+unifdef: addsym ZIG=BAR
+unifdef: addsym QUX=QUX
+unifdef: findsym BAR=ZIG
+unifdef: indir... FOO=BAR
+unifdef: ...ectsym FOO=ZIG
+unifdef: findsym ZIG=BAR
+unifdef: indir... BAR=ZIG
+unifdef: ...ectsym BAR=BAR
+unifdef: findsym BAR=BAR
+unifdef: findsym QUX=QUX
+unifdef: findsym ZIG=BAR
+unifdef: indir... FOO=ZIG
+unifdef: ...ectsym FOO=BAR
+unifdef: findsym BAR=BAR
+unifdef: findsym BAR=BAR
+unifdef: findsym QUX=QUX
+unifdef: findsym BAR=BAR
+unifdef: findsym BAR=BAR
+unifdef: findsym BAR=BAR
+unifdef: findsym QUX=QUX
+unifdef: parser line 1 state C comment START line
+unifdef: process line 1 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 2 state C comment START line
+unifdef: process line 2 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 3 state NO comment START line
+unifdef: process line 3 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 4 state NO comment START line
+unifdef: process line 4 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 5 state NO comment START line
+unifdef: process line 5 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 6 state NO comment START line
+unifdef: process line 6 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 7 state NO comment START line
+unifdef: process line 7 PLAIN -> OUTSIDE depth 0
+unifdef: eval  FOO
+
+unifdef: eval0
+unifdef: eval1
+unifdef: eval2
+unifdef: eval3
+unifdef: eval4
+unifdef: eval5
+unifdef: eval6
+unifdef: eval7
+unifdef: eval8
+unifdef: eval9
+unifdef: eval10 symbol
+unifdef: findsym FOO=BAR
+unifdef: eval = 0
+unifdef: parser line 8 state NO comment START line
+unifdef: process line 8 IF -> PASS_MIDDLE depth 1
+unifdef: parser line 9 state NO comment START line
+unifdef: process line 9 PLAIN -> PASS_MIDDLE depth 1
+unifdef: parser line 10 state NO comment START line
+unifdef: process line 10 ELSE -> PASS_ELSE depth 1
+unifdef: parser line 11 state NO comment START line
+unifdef: process line 11 PLAIN -> PASS_ELSE depth 1
+unifdef: parser line 12 state NO comment START line
+unifdef: process line 12 ENDIF -> OUTSIDE depth 0
+unifdef: parser line 13 state NO comment START line
+unifdef: process line 13 PLAIN -> OUTSIDE depth 0
+unifdef: eval  BAR
+
+unifdef: eval0
+unifdef: eval1
+unifdef: eval2
+unifdef: eval3
+unifdef: eval4
+unifdef: eval5
+unifdef: eval6
+unifdef: eval7
+unifdef: eval8
+unifdef: eval9
+unifdef: eval10 symbol
+unifdef: findsym BAR=BAR
+unifdef: eval = 0
+unifdef: parser line 14 state NO comment START line
+unifdef: process line 14 IF -> PASS_MIDDLE depth 1
+unifdef: parser line 15 state NO comment START line
+unifdef: process line 15 PLAIN -> PASS_MIDDLE depth 1
+unifdef: eval  FOO
+
+unifdef: eval0
+unifdef: eval1
+unifdef: eval2
+unifdef: eval3
+unifdef: eval4
+unifdef: eval5
+unifdef: eval6
+unifdef: eval7
+unifdef: eval8
+unifdef: eval9
+unifdef: eval10 symbol
+unifdef: findsym FOO=BAR
+unifdef: eval = 0
+unifdef: parser line 16 state NO comment START line
+unifdef: process line 16 ELIF -> PASS_MIDDLE depth 1
+unifdef: parser line 17 state NO comment START line
+unifdef: process line 17 PLAIN -> PASS_MIDDLE depth 1
+unifdef: parser line 18 state NO comment START line
+unifdef: process line 18 ELSE -> PASS_ELSE depth 1
+unifdef: parser line 19 state NO comment START line
+unifdef: process line 19 PLAIN -> PASS_ELSE depth 1
+unifdef: parser line 20 state NO comment START line
+unifdef: process line 20 ENDIF -> OUTSIDE depth 0
+unifdef: parser line 21 state NO comment START line
+unifdef: process line 21 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 22 state NO comment START line
+unifdef: process line 22 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 23 state NO comment START line
+unifdef: process line 23 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 24 state NO comment START line
+unifdef: process line 24 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 25 state NO comment START line
+unifdef: process line 25 PLAIN -> OUTSIDE depth 0
+unifdef: parser line 26 state NO comment START line
+unifdef: process line 26 PLAIN -> OUTSIDE depth 0
+unifdef: process line 27 EOF -> OUTSIDE depth 0
diff --git a/contrib/unifdef/tests/recursive.expout b/contrib/unifdef/tests/recursive.expout
new file mode 100644
index 000000000000..9e588c22791c
--- /dev/null
+++ b/contrib/unifdef/tests/recursive.expout
@@ -0,0 +1,26 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+#if BAR
+int foo() { return 0; }
+#elif FOO
+int bar() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+  bar();
+}
diff --git a/contrib/unifdef/tests/recursive.exprc b/contrib/unifdef/tests/recursive.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/recursive.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/recursive.sh b/contrib/unifdef/tests/recursive.sh
new file mode 100644
index 000000000000..eb857de7e133
--- /dev/null
+++ b/contrib/unifdef/tests/recursive.sh
@@ -0,0 +1 @@
+unifdef -d -DFOO=BAR -DBAR=ZIG -DZIG=BAR -DQUX=QUX if1.c
diff --git a/contrib/unifdef/tests/small1.c b/contrib/unifdef/tests/small1.c
new file mode 100644
index 000000000000..eb1c26d0851c
--- /dev/null
+++ b/contrib/unifdef/tests/small1.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifdef FOO
+int foo() { return 0; }
+#else
+#error FOO not defined
+#endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/small1.experr b/contrib/unifdef/tests/small1.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/small1.expout b/contrib/unifdef/tests/small1.expout
new file mode 100644
index 000000000000..b64cfc265bd2
--- /dev/null
+++ b/contrib/unifdef/tests/small1.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/small1.exprc b/contrib/unifdef/tests/small1.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/small1.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/small1.sh b/contrib/unifdef/tests/small1.sh
new file mode 100644
index 000000000000..b948726042ec
--- /dev/null
+++ b/contrib/unifdef/tests/small1.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR small1.c
diff --git a/contrib/unifdef/tests/small2.c b/contrib/unifdef/tests/small2.c
new file mode 100644
index 000000000000..4a5c813cb0f4
--- /dev/null
+++ b/contrib/unifdef/tests/small2.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifndef BAR
+int bar() { return 0; }
+#else
+#error BAR not defined
+#endif
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/small2.experr b/contrib/unifdef/tests/small2.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/small2.expout b/contrib/unifdef/tests/small2.expout
new file mode 100644
index 000000000000..5c1f8b4f23f0
--- /dev/null
+++ b/contrib/unifdef/tests/small2.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int bar() { return 0; }
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/small2.exprc b/contrib/unifdef/tests/small2.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/small2.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/small2.sh b/contrib/unifdef/tests/small2.sh
new file mode 100644
index 000000000000..fdedd7d88f2e
--- /dev/null
+++ b/contrib/unifdef/tests/small2.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR small2.c
diff --git a/contrib/unifdef/tests/spaces1.c b/contrib/unifdef/tests/spaces1.c
new file mode 100644
index 000000000000..947dacf55fa1
--- /dev/null
+++ b/contrib/unifdef/tests/spaces1.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+# include <stdlib.h>
+
+# ifdef FOO
+int foo() { return 0; }
+# else
+#  error FOO not defined
+# endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/spaces1.experr b/contrib/unifdef/tests/spaces1.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/spaces1.expout b/contrib/unifdef/tests/spaces1.expout
new file mode 100644
index 000000000000..766f2358b55e
--- /dev/null
+++ b/contrib/unifdef/tests/spaces1.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+# include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/spaces1.exprc b/contrib/unifdef/tests/spaces1.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/spaces1.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/spaces1.sh b/contrib/unifdef/tests/spaces1.sh
new file mode 100644
index 000000000000..e5ef62bc65bb
--- /dev/null
+++ b/contrib/unifdef/tests/spaces1.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR spaces1.c
diff --git a/contrib/unifdef/tests/spaces2.c b/contrib/unifdef/tests/spaces2.c
new file mode 100644
index 000000000000..f5a250a1ee69
--- /dev/null
+++ b/contrib/unifdef/tests/spaces2.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+# include <stdlib.h>
+
+# ifndef BAR
+int bar() { return 0; }
+# else
+#  error BAR defined
+# endif
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/spaces2.experr b/contrib/unifdef/tests/spaces2.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/spaces2.expout b/contrib/unifdef/tests/spaces2.expout
new file mode 100644
index 000000000000..7d377599b7c3
--- /dev/null
+++ b/contrib/unifdef/tests/spaces2.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+# include <stdlib.h>
+
+int bar() { return 0; }
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/spaces2.exprc b/contrib/unifdef/tests/spaces2.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/spaces2.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/spaces2.sh b/contrib/unifdef/tests/spaces2.sh
new file mode 100644
index 000000000000..cb80f89d5b75
--- /dev/null
+++ b/contrib/unifdef/tests/spaces2.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR spaces2.c
diff --git a/contrib/unifdef/tests/spaces3.c b/contrib/unifdef/tests/spaces3.c
new file mode 100644
index 000000000000..7284634a2968
--- /dev/null
+++ b/contrib/unifdef/tests/spaces3.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+ # include <stdlib.h>
+
+ # ifndef BAR
+int bar() { return 0; }
+ # else
+   # error BAR defined
+ # endif
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/spaces3.experr b/contrib/unifdef/tests/spaces3.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/spaces3.expout b/contrib/unifdef/tests/spaces3.expout
new file mode 100644
index 000000000000..60aceee7571d
--- /dev/null
+++ b/contrib/unifdef/tests/spaces3.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+ # include <stdlib.h>
+
+int bar() { return 0; }
+
+int main()
+{
+  bar();
+}
diff --git a/contrib/unifdef/tests/spaces3.exprc b/contrib/unifdef/tests/spaces3.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/spaces3.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/spaces3.sh b/contrib/unifdef/tests/spaces3.sh
new file mode 100644
index 000000000000..0bce1847ab0c
--- /dev/null
+++ b/contrib/unifdef/tests/spaces3.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR spaces3.c
diff --git a/contrib/unifdef/tests/spaces4.c b/contrib/unifdef/tests/spaces4.c
new file mode 100644
index 000000000000..6fbc6f239891
--- /dev/null
+++ b/contrib/unifdef/tests/spaces4.c
@@ -0,0 +1,17 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+ # include <stdlib.h>
+
+ # ifdef FOO
+int foo() { return 0; }
+ # else
+   # error FOO defined
+ # endif
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/spaces4.experr b/contrib/unifdef/tests/spaces4.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/spaces4.expout b/contrib/unifdef/tests/spaces4.expout
new file mode 100644
index 000000000000..fbf0d3cba46b
--- /dev/null
+++ b/contrib/unifdef/tests/spaces4.expout
@@ -0,0 +1,13 @@
+/* Copyright 2004 Bob Proulx <bob@proulx.com>
+Distributed under the two-clause BSD licence;
+see the COPYING file for details. */
+
+# include <stdio.h>
+ # include <stdlib.h>
+
+int foo() { return 0; }
+
+int main()
+{
+  foo();
+}
diff --git a/contrib/unifdef/tests/spaces4.exprc b/contrib/unifdef/tests/spaces4.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/spaces4.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/spaces4.sh b/contrib/unifdef/tests/spaces4.sh
new file mode 100644
index 000000000000..1390ab7870ac
--- /dev/null
+++ b/contrib/unifdef/tests/spaces4.sh
@@ -0,0 +1 @@
+unifdef -DFOO=1 -DFOOB=42 -UBAR spaces4.c
diff --git a/contrib/unifdef/tests/whitespace-1.experr b/contrib/unifdef/tests/whitespace-1.experr
new file mode 100644
index 000000000000..cb23fce713ce
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-1.experr
@@ -0,0 +1,2 @@
+unifdef: whitespace.c: 4: Obfuscated preprocessor control line (#if line 1 depth 1)
+unifdef: Output may be truncated
diff --git a/contrib/unifdef/tests/whitespace-1.expout b/contrib/unifdef/tests/whitespace-1.expout
new file mode 100644
index 000000000000..257cc5642cb1
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-1.expout
@@ -0,0 +1 @@
+foo
diff --git a/contrib/unifdef/tests/whitespace-1.exprc b/contrib/unifdef/tests/whitespace-1.exprc
new file mode 100644
index 000000000000..0cfbf08886fc
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-1.exprc
@@ -0,0 +1 @@
+2
diff --git a/contrib/unifdef/tests/whitespace-1.sh b/contrib/unifdef/tests/whitespace-1.sh
new file mode 100644
index 000000000000..51ad39bc1768
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-1.sh
@@ -0,0 +1 @@
+unifdef -DFOO whitespace.c
diff --git a/contrib/unifdef/tests/whitespace-2.experr b/contrib/unifdef/tests/whitespace-2.experr
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/contrib/unifdef/tests/whitespace-2.expout b/contrib/unifdef/tests/whitespace-2.expout
new file mode 100644
index 000000000000..84cabfea1056
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-2.expout
@@ -0,0 +1,5 @@
+#ifdef FOO
+foo
+#endif                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        //spong
+
+bar
diff --git a/contrib/unifdef/tests/whitespace-2.exprc b/contrib/unifdef/tests/whitespace-2.exprc
new file mode 100644
index 000000000000..d00491fd7e5b
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-2.exprc
@@ -0,0 +1 @@
+1
diff --git a/contrib/unifdef/tests/whitespace-2.sh b/contrib/unifdef/tests/whitespace-2.sh
new file mode 100644
index 000000000000..1aa178b5e071
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace-2.sh
@@ -0,0 +1 @@
+unifdef -DBAR whitespace.c
diff --git a/contrib/unifdef/tests/whitespace.c b/contrib/unifdef/tests/whitespace.c
new file mode 100644
index 000000000000..de0b9e4be176
--- /dev/null
+++ b/contrib/unifdef/tests/whitespace.c
@@ -0,0 +1,7 @@
+#ifdef FOO
+foo
+#endif                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        //spong
+
+#ifdef BAR
+bar
+#endif
\ No newline at end of file
diff --git a/contrib/unifdef/tests/xterm.experr b/contrib/unifdef/tests/xterm.experr
new file mode 100644
index 000000000000..7938dcdde861
--- /dev/null
+++ b/contrib/unifdef/tests/xterm.experr
@@ -0,0 +1,3 @@
+0
+1
+0
diff --git a/contrib/unifdef/tests/xterm.expout b/contrib/unifdef/tests/xterm.expout
new file mode 100644
index 000000000000..d05d26545dbb
--- /dev/null
+++ b/contrib/unifdef/tests/xterm.expout
@@ -0,0 +1,83 @@
+#define RES_OFFSET(field)	XtOffsetOf(XTERM_RESOURCE, field)
+#include <xterm.h>
+#include <version.h>
+#include <X11/cursorfont.h>
+#include <X11/Xlocale.h>
+#include <pwd.h>
+#include <ctype.h>
+#include <data.h>
+#include <error.h>
+#include <menu.h>
+#include <main.h>
+#include <xstrings.h>
+#include <xtermcap.h>
+#include <xterm_io.h>
+#include <sys/stat.h>
+#include <sys/resource.h>
+#define HAS_BSD_GROUPS
+#include <sys/param.h>		/* for NOFILE */
+#define WTMP
+#include <stdio.h>
+#define UTMP_STR utmp
+#include <libutil.h>		/* openpty() */
+#include <signal.h>
+#include <sys/wait.h>
+#define TERMCAP_ERASE "kb"
+#define VAL_INITIAL_ERASE A2E(8)
+#define VAL_LINE_SPEED B38400
+#define TERMIO_STRUCT struct termios
+#define ttySetAttr(fd, datap) tcsetattr(fd, TCSANOW, datap)
+#define ttyGetAttr(fd, datap) tcgetattr(fd, datap)
+#define ttyFlush(fd)          tcflush(fd, TCOFLUSH)
+#define TTYMODE(name) { name, sizeof(name)-1, 0, 0 }
+#define XTTYMODE_intr	0
+#define XTTYMODE_quit	1
+#define XTTYMODE_erase	2
+#define XTTYMODE_kill	3
+#define XTTYMODE_eof	4
+#define XTTYMODE_eol	5
+#define XTTYMODE_swtch	6
+#define XTTYMODE_start	7
+#define XTTYMODE_stop	8
+#define XTTYMODE_brk	9
+#define XTTYMODE_susp	10
+#define XTTYMODE_dsusp	11
+#define XTTYMODE_rprnt	12
+#define XTTYMODE_flush	13
+#define XTTYMODE_weras	14
+#define XTTYMODE_lnext	15
+#define XTTYMODE_status	16
+#define XTTYMODE_erase2	17
+#define XTTYMODE_eol2	18
+#define validTtyChar(data, n) \
+#define TMODE(ind,var) if (ttymodelist[ind].set) var = (cc_t) ttymodelist[ind].value
+#include <X11/Xmu/SysUtil.h>	/* XmuGetHostname */
+#define MIT_CONSOLE_LEN	12
+#define MIT_CONSOLE "MIT_CONSOLE_"
+#define SetUtmpHost(dst, screen) \
+{"#",		".iconGeometry",XrmoptionStickyArg,	(XPointer) NULL},
+{ "#geom",                 "icon window geometry" },
+    TRACE(("...decode_keyvalue %#x\n", value));
+#define isOption(string) (Boolean)((string)[0] == '-' || (string)[0] == '+')
+#define DATA(option,kind) { option, NULL, kind, (XtPointer) NULL }
+#undef DATA
+#define ITEM(n) ((Cardinal)(n) < XtNumber(optionDescList) \
+#undef ITEM
+#define disableSetUid()		/* nothing */
+#define disableSetGid()		/* nothing */
+#define DATA(name) { #name, es##name }
+#undef DATA
+#define USE_OPENPTY 1
+#define NO_FDS {-1, -1}
+#define TRACE_HANDSHAKE(tag, data)	/* nothing */
+    TRACE(("set_owner(%s, uid=%d, gid=%d, mode=%#o\n",
+		TRACE(("...stat uid=%d, gid=%d, mode=%#o\n",
+#define close_fd(fd) close(fd), fd = -1
+#define USE_NO_DEV_TTY 1
+	if ((ptr1 = x_strindex(oldtc, "co#")) == NULL) {
+	    strcat(oldtc, "co#80:");
+	    ptr1 = x_strindex(oldtc, "co#");
+	if ((ptr2 = x_strindex(oldtc, "li#")) == NULL) {
+	    strcat(oldtc, "li#24:");
+	    ptr2 = x_strindex(oldtc, "li#");
+	    TRACE(("...parsed #%d: %s=%#x\n", count, mp->name, c));
diff --git a/contrib/unifdef/tests/xterm.exprc b/contrib/unifdef/tests/xterm.exprc
new file mode 100644
index 000000000000..573541ac9702
--- /dev/null
+++ b/contrib/unifdef/tests/xterm.exprc
@@ -0,0 +1 @@
+0
diff --git a/contrib/unifdef/tests/xterm.sh b/contrib/unifdef/tests/xterm.sh
new file mode 100644
index 000000000000..88c856bceef4
--- /dev/null
+++ b/contrib/unifdef/tests/xterm.sh
@@ -0,0 +1,35 @@
+# hacks so we don't have to distribute huge chunks of XTerm
+
+if [ ! -f xterm-really ]
+then
+	cat xterm.expout
+	cat xterm.experr 1>&2
+	exit $(cat xterm.exprc)
+fi
+if [ -f xterm-clean ]
+then
+	rm xterm.tar.gz xterm-defs.h xterm-main.c
+fi
+
+if [ ! -f xterm.tar.gz ]
+then
+	wget -q http://invisible-island.net/datafiles/release/xterm.tar.gz
+fi
+if [ ! -f xterm-main.c ]
+then
+	tar xf xterm.tar.gz
+	cd xterm-[0-9][0-9][0-9]
+	gcc -I/usr/X11R6/include -I. -E -dM \
+		main.c > ../xterm-defs.h
+	cat     main.c > ../xterm-main.c
+	cd ..
+	rm -r xterm-[0-9][0-9][0-9]
+fi
+
+unifdef -s xterm-main.c | sed 's/^/#undef /' >xterm-undefs.h
+echo $? 1>&2
+unifdef -f xterm-undefs.h -f xterm-defs.h xterm-main.c >xterm-out.c
+echo $? 1>&2
+grep '#' xterm-out.c
+echo $? 1>&2
+rm -f xterm-undefs.h xterm-out.c
diff --git a/contrib/unifdef/unifdef.1 b/contrib/unifdef/unifdef.1
new file mode 100644
index 000000000000..0e349d6fd5a3
--- /dev/null
+++ b/contrib/unifdef/unifdef.1
@@ -0,0 +1,530 @@
+.\" Copyright (c) 1985, 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\" Copyright (c) 2002 - 2015 Tony Finch <dot@dotat.at>.  All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" Dave Yost. It was rewritten to support ANSI C by Tony Finch.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.Dd December 3, 2015
+.Dt UNIFDEF 1 PRM
+.Os " "
+.Sh NAME
+.Nm unifdef , unifdefall
+.Nd remove preprocessor conditionals from code
+.Sh SYNOPSIS
+.Nm
+.Op Fl bBcdehKkmnsStV
+.Op Fl I Ns Ar path
+.Op Fl [i]D Ns Ar sym Ns Op = Ns Ar val
+.Op Fl [i]U Ns Ar sym
+.Ar ...
+.Op Fl f Ar defile
+.Op Fl x Bro Ar 012 Brc
+.Op Fl M Ar backext
+.Op Fl o Ar outfile
+.Op Ar infile ...
+.Nm unifdefall
+.Op Fl I Ns Ar path
+.Ar ...
+.Ar file
+.Sh DESCRIPTION
+The
+.Nm
+utility selectively processes conditional
+.Xr cpp 1
+directives.
+It removes from a file
+both the directives
+and any additional text that they specify should be removed,
+while otherwise leaving the file alone.
+.Pp
+The
+.Nm
+utility acts on
+.Ic #if , #ifdef , #ifndef ,
+.Ic #elif , #else ,
+and
+.Ic #endif
+lines,
+using macros specified in
+.Fl D
+and
+.Fl U
+command line options or in
+.Fl f
+definitions files.
+A directive is processed
+if the macro specifications are sufficient to provide
+a definite value for its control expression.
+If the result is false,
+the directive and the following lines under its control are removed.
+If the result is true,
+only the directive is removed.
+An
+.Ic #ifdef
+or
+.Ic #ifndef
+directive is passed through unchanged
+if its controlling macro is not specified.
+Any
+.Ic #if
+or
+.Ic #elif
+control expression that has an unknown value or that
+.Nm
+cannot parse is passed through unchanged.
+By default,
+.Nm
+ignores
+.Ic #if
+and
+.Ic #elif
+lines with constant expressions;
+it can be told to process them by specifying the
+.Fl k
+flag on the command line.
+.Pp
+It understands a commonly-used subset
+of the expression syntax for
+.Ic #if
+and
+.Ic #elif
+lines:
+integer constants,
+integer values of macros defined on the command line,
+the
+.Fn defined
+operator,
+the operators
+.Ic \&! , ~ , -
+(unary),
+.Ic * , / , % , + , - ,
+.Ic < , <= , > , >= , == , != , & , ^ , \&| ,
+.Ic && , || ,
+and parenthesized expressions.
+Division by zero is treated as an unknown value.
+A kind of
+.Dq "short circuit"
+evaluation is used for the
+.Ic &&
+operator:
+if either operand is definitely false then the result is false,
+even if the value of the other operand is unknown.
+Similarly,
+if either operand of
+.Ic ||
+is definitely true then the result is true.
+.Pp
+When evaluating an expression,
+.Nm
+does not expand macros first.
+The value of a macro must be a simple number,
+not an expression.
+A limited form of indirection is allowed,
+where one macro's value is the name of another.
+.Pp
+In most cases,
+.Nm
+does not distinguish between object-like macros
+(without arguments) and function-like macros (with arguments).
+A function-like macro invocation can appear in
+.Ic #if
+and
+.Ic #elif
+control expressions.
+If the macro is not explicitly defined,
+or is defined with the
+.Fl D
+flag on the command-line,
+or with
+.Ic #define
+in a
+.Fl f
+definitions file,
+its arguments are ignored.
+If a macro is explicitly undefined on the command line with the
+.Fl U
+flag,
+or with
+.Ic #undef
+in a
+.Fl f
+definitions file,
+it may not have any arguments since this leads to a syntax error.
+.Pp
+The
+.Nm
+utility understands just enough about C
+to know when one of the directives is inactive
+because it is inside
+a comment,
+or cannot be evaluated because it is split by a backslash-continued line.
+It spots unusually-formatted preprocessor directives
+and passes them through unchanged when the layout is too odd for it to handle.
+(See the
+.Sx BUGS
+section below.)
+.Pp
+A script called
+.Nm unifdefall
+can be used to remove all conditional
+.Xr cpp 1
+directives from a file.
+It uses
+.Nm Fl s
+and
+.Nm cpp Fl dM
+to get lists of all the controlling macros
+and their definitions (or lack thereof),
+then invokes
+.Nm
+with appropriate arguments to process the file.
+.Sh OPTIONS
+.Bl -tag -width indent -compact
+.It Fl D Ns Ar sym Ns = Ns Ar val
+Specify that a macro is defined to a given value.
+.Pp
+.It Fl D Ns Ar sym
+Specify that a macro is defined to the value 1.
+.Pp
+.It Fl U Ns Ar sym
+Specify that a macro is undefined.
+.Pp
+If the same macro appears in more than one argument,
+the last occurrence dominates.
+.Pp
+.It Fl iD Ns Ar sym Ns Op = Ns Ar val
+.It Fl iU Ns Ar sym
+C strings, comments,
+and line continuations
+are ignored within
+.Ic #ifdef
+and
+.Ic #ifndef
+blocks
+controlled by macros
+specified with these options.
+.Pp
+.It Fl f Ar defile
+The file
+.Ar defile
+contains
+.Ic #define
+and
+.Ic #undef
+preprocessor directives,
+which have the same effect as the corresponding
+.Fl D
+and
+.Fl U
+command-line arguments.
+You can have multiple
+.Fl f
+arguments and mix them with
+.Fl D
+and
+.Fl U
+arguments;
+later options override earlier ones.
+.Pp
+Each directive must be on a single line.
+Object-like macro definitions (without arguments)
+are set to the given value.
+Function-like macro definitions (with arguments)
+are treated as if they are set to 1.
+.Pp
+.Em Warning:
+string literals and character constants are not parsed correctly in
+.Fl f
+files.
+.Pp
+.It Fl b
+Replace removed lines with blank lines
+instead of deleting them.
+Mutually exclusive with the
+.Fl B
+option.
+.Pp
+.It Fl B
+Compress blank lines around a deleted section.
+Mutually exclusive with the
+.Fl b
+option.
+.Pp
+.It Fl c
+Complement,
+i.e., lines that would have been removed or blanked
+are retained and vice versa.
+.Pp
+.It Fl d
+Turn on printing of debugging messages.
+.Pp
+.It Fl e
+By default,
+.Nm
+will report an error if it needs to remove
+a preprocessor directive that spans more than one line,
+for example, if it has a multi-line
+comment hanging off its right hand end.
+The
+.Fl e
+flag makes it ignore the line instead.
+.Pp
+.It Fl h
+Print help.
+.Pp
+.It Fl I Ns Ar path
+Specifies to
+.Nm unifdefall
+an additional place to look for
+.Ic #include
+files.
+This option is ignored by
+.Nm
+for compatibility with
+.Xr cpp 1
+and to simplify the implementation of
+.Nm unifdefall .
+.Pp
+.It Fl K
+Always treat the result of
+.Ic &&
+and
+.Ic ||
+operators as unknown if either operand is unknown,
+instead of short-circuiting when unknown operands can't affect the result.
+This option is for compatibility with older versions of
+.Nm .
+.Pp
+.It Fl k
+Process
+.Ic #if
+and
+.Ic #elif
+lines with constant expressions.
+By default, sections controlled by such lines are passed through unchanged
+because they typically start
+.Dq Li "#if 0"
+and are used as a kind of comment to sketch out future or past development.
+It would be rude to strip them out, just as it would be for normal comments.
+.Pp
+.It Fl m
+Modify one or more input files in place.
+If an input file is not modified,
+the original is preserved instead of being overwritten with an identical copy.
+.Pp
+.It Fl M Ar backext
+Modify input files in place, and keep backups of the original files by
+appending the
+.Ar backext
+to the input filenames.
+A zero length
+.Ar backext
+behaves the same as the
+.Fl m
+option.
+.Pp
+.It Fl n
+Add
+.Li #line
+directives to the output following any deleted lines,
+so that errors produced when compiling the output file correspond to
+line numbers in the input file.
+.Pp
+.It Fl o Ar outfile
+Write output to the file
+.Ar outfile
+instead of the standard output when processing a single file.
+.Pp
+.It Fl s
+Instead of processing an input file as usual,
+this option causes
+.Nm
+to produce a list of macros that are used in
+preprocessor directive controlling expressions.
+.Pp
+.It Fl S
+Like the
+.Fl s
+option, but the nesting depth of each macro is also printed.
+This is useful for working out the number of possible combinations
+of interdependent defined/undefined macros.
+.Pp
+.It Fl t
+Disables parsing for C strings, comments,
+and line continuations,
+which is useful
+for plain text.
+This is a blanket version of the
+.Fl iD
+and
+.Fl iU
+flags.
+.Pp
+.It Fl V
+Print version details.
+.Pp
+.It Fl x Bro Ar 012 Brc
+Set exit status mode to zero, one, or two.
+See the
+.Sx EXIT STATUS
+section below for details.
+.El
+.Pp
+The
+.Nm
+utility takes its input from
+.Em stdin
+if there are no
+.Ar file
+arguments.
+You must use the
+.Fl m
+or
+.Fl M
+options if there are multiple input files.
+You can specify input from stdin or output to stdout with
+.Ql - .
+.Pp
+The
+.Nm
+utility works nicely with the
+.Fl D Ns Ar sym
+option of
+.Xr diff 1 .
+.Sh EXIT STATUS
+In normal usage the
+.Nm
+utility's exit status depends on the mode set using the
+.Fl x
+option.
+.Pp
+If the exit mode is zero (the default) then
+.Nm
+exits with status 0 if the output is an exact copy of the input,
+or with status 1 if the output differs.
+.Pp
+If the exit mode is one,
+.Nm
+exits with status 1 if the output is unmodified
+or 0 if it differs.
+.Pp
+If the exit mode is two,
+.Nm
+exits with status zero in both cases.
+.Pp
+In all exit modes,
+.Nm
+exits with status 2 if there is an error.
+.Pp
+The exit status is 0 if the
+.Fl h
+or
+.Fl V
+command line options are given.
+.Sh DIAGNOSTICS
+.Bl -item
+.It
+.Tn EOF
+in comment
+.It
+Inappropriate
+.Ic #elif ,
+.Ic #else
+or
+.Ic #endif
+.It
+Missing macro name in #define or #undef
+.It
+Obfuscated preprocessor control line
+.It
+Premature
+.Tn EOF
+(with the line number of the most recent unterminated
+.Ic #if )
+.It
+Too many levels of nesting
+.It
+Unrecognized preprocessor directive
+.It
+Unterminated char or string literal
+.El
+.Sh SEE ALSO
+.Xr cpp 1 ,
+.Xr diff 1
+.Pp
+The unifdef home page is
+.Pa http://dotat.at/prog/unifdef
+.Sh HISTORY
+The
+.Nm
+command appeared in
+.Bx 2.9 .
+.Tn ANSI\~C
+support was added in
+.Fx 4.7 .
+.Sh AUTHORS
+.An -nosplit
+The original implementation was written by
+.An Dave Yost Aq Mt Dave@Yost.com .
+.An Tony Finch Aq Mt dot@dotat.at
+rewrote it to support
+.Tn ANSI\~C .
+.Sh BUGS
+.Bl -bullet
+.It
+Expression evaluation is very limited.
+.It
+Character constants are not evaluated.
+String literals and character constants in
+.Fl f
+definition files are ignored rather than parsed as
+part of a macro's replacement tokens.
+.It
+Only the basic form of C++ raw string literals is recognized,
+like
+.Li R"(string)"
+without delimiters as in
+.Li R"delimiter(string)delimiter" .
+.It
+Source files are processed one line at a time,
+so preprocessor directives split across more than one physical line
+(because of comments or backslash-newline)
+cannot be handled in every situation.
+.It
+Trigraphs are not recognized.
+.It
+There is no support for macros with different definitions at
+different points in the source file.
+.It
+The text-mode and ignore functionality does not correspond to modern
+.Xr cpp 1
+behaviour.
+.El
+.Pp
+Please send bug reports by email to
+.Aq Mt dot@dotat.at .
diff --git a/contrib/unifdef/unifdef.c b/contrib/unifdef/unifdef.c
new file mode 100644
index 000000000000..82f6acd66038
--- /dev/null
+++ b/contrib/unifdef/unifdef.c
@@ -0,0 +1,1702 @@
+/*
+ * Copyright (c) 2002 - 2020 Tony Finch <dot@dotat.at>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * unifdef - remove ifdef'ed lines
+ *
+ * This code was derived from software contributed to Berkeley by Dave Yost.
+ * It was rewritten to support ANSI C by Tony Finch. The original version
+ * of unifdef carried the 4-clause BSD copyright licence. None of its code
+ * remains in this version (though some of the names remain) so it now
+ * carries a more liberal licence.
+ *
+ *  Wishlist:
+ *      provide an option which will append the name of the
+ *        appropriate symbol after #else's and #endif's
+ *      provide an option which will check symbols after
+ *        #else's and #endif's to see that they match their
+ *        corresponding #ifdef or #ifndef
+ *
+ *   These require better buffer handling, which would also make
+ *   it possible to handle all "dodgy" directives correctly.
+ */
+
+#include "unifdef.h"
+
+static const char copyright[] =
+    #include "version.h"
+    "@(#) $Author: Tony Finch (dot@dotat.at) $\n"
+    "@(#) $URL: http://dotat.at/prog/unifdef $\n"
+;
+
+/* types of input lines: */
+typedef enum {
+	LT_TRUEI,		/* a true #if with ignore flag */
+	LT_FALSEI,		/* a false #if with ignore flag */
+	LT_IF,			/* an unknown #if */
+	LT_TRUE,		/* a true #if */
+	LT_FALSE,		/* a false #if */
+	LT_ELIF,		/* an unknown #elif */
+	LT_ELTRUE,		/* a true #elif */
+	LT_ELFALSE,		/* a false #elif */
+	LT_ELSE,		/* #else */
+	LT_ENDIF,		/* #endif */
+	LT_DODGY,		/* flag: directive is not on one line */
+	LT_DODGY_LAST = LT_DODGY + LT_ENDIF,
+	LT_PLAIN,		/* ordinary line */
+	LT_EOF,			/* end of file */
+	LT_ERROR,		/* unevaluable #if */
+	LT_COUNT
+} Linetype;
+
+static char const * const linetype_name[] = {
+	"TRUEI", "FALSEI", "IF", "TRUE", "FALSE",
+	"ELIF", "ELTRUE", "ELFALSE", "ELSE", "ENDIF",
+	"DODGY TRUEI", "DODGY FALSEI",
+	"DODGY IF", "DODGY TRUE", "DODGY FALSE",
+	"DODGY ELIF", "DODGY ELTRUE", "DODGY ELFALSE",
+	"DODGY ELSE", "DODGY ENDIF",
+	"PLAIN", "EOF", "ERROR"
+};
+
+#define linetype_if2elif(lt) ((Linetype)(lt - LT_IF + LT_ELIF))
+#define linetype_2dodgy(lt) ((Linetype)(lt + LT_DODGY))
+
+/* state of #if processing */
+typedef enum {
+	IS_OUTSIDE,
+	IS_FALSE_PREFIX,	/* false #if followed by false #elifs */
+	IS_TRUE_PREFIX,		/* first non-false #(el)if is true */
+	IS_PASS_MIDDLE,		/* first non-false #(el)if is unknown */
+	IS_FALSE_MIDDLE,	/* a false #elif after a pass state */
+	IS_TRUE_MIDDLE,		/* a true #elif after a pass state */
+	IS_PASS_ELSE,		/* an else after a pass state */
+	IS_FALSE_ELSE,		/* an else after a true state */
+	IS_TRUE_ELSE,		/* an else after only false states */
+	IS_FALSE_TRAILER,	/* #elifs after a true are false */
+	IS_COUNT
+} Ifstate;
+
+static char const * const ifstate_name[] = {
+	"OUTSIDE", "FALSE_PREFIX", "TRUE_PREFIX",
+	"PASS_MIDDLE", "FALSE_MIDDLE", "TRUE_MIDDLE",
+	"PASS_ELSE", "FALSE_ELSE", "TRUE_ELSE",
+	"FALSE_TRAILER"
+};
+
+/* state of comment parser */
+typedef enum {
+	NO_COMMENT = false,	/* outside a comment */
+	C_COMMENT,		/* in a comment like this one */
+	CXX_COMMENT,		/* between // and end of line */
+	STARTING_COMMENT,	/* just after slash-backslash-newline */
+	FINISHING_COMMENT,	/* star-backslash-newline in a C comment */
+	CHAR_LITERAL,		/* inside '' */
+	STRING_LITERAL,		/* inside "" */
+	RAW_STRING_LITERAL	/* inside R"()" */
+} Comment_state;
+
+static char const * const comment_name[] = {
+	"NO", "C", "CXX", "STARTING", "FINISHING", "CHAR", "STRING"
+};
+
+/* state of preprocessor line parser */
+typedef enum {
+	LS_START,		/* only space and comments on this line */
+	LS_HASH,		/* only space, comments, and a hash */
+	LS_DIRTY		/* this line can't be a preprocessor line */
+} Line_state;
+
+static char const * const linestate_name[] = {
+	"START", "HASH", "DIRTY"
+};
+
+/*
+ * Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1
+ */
+#define	MAXDEPTH        64			/* maximum #if nesting */
+#define	MAXLINE         4096			/* maximum length of line */
+
+/*
+ * Sometimes when editing a keyword the replacement text is longer, so
+ * we leave some space at the end of the tline buffer to accommodate this.
+ */
+#define	EDITSLOP        10
+
+/*
+ * C17/18 allow 63 characters per macro name, but up to 127 arbitrarily large
+ * parameters.
+ */
+struct macro {
+	RB_ENTRY(macro)	entry;
+	const char	*name;
+	const char	*value;
+	bool		ignore;		/* -iDsym or -iUsym */
+};
+
+static int
+macro_cmp(struct macro *a, struct macro *b)
+{
+	return (strcmp(a->name, b->name));
+}
+
+static RB_HEAD(MACROMAP, macro) macro_tree = RB_INITIALIZER(&macro_tree);
+RB_GENERATE_STATIC(MACROMAP, macro, entry, macro_cmp);
+
+/*
+ * Globals.
+ */
+
+static bool             compblank;		/* -B: compress blank lines */
+static bool             lnblank;		/* -b: blank deleted lines */
+static bool             complement;		/* -c: do the complement */
+static bool             debugging;		/* -d: debugging reports */
+static bool             inplace;		/* -m: modify in place */
+static bool             iocccok;		/* -e: fewer IOCCC errors */
+static bool             strictlogic;		/* -K: keep ambiguous #ifs */
+static bool             killconsts;		/* -k: eval constant #ifs */
+static bool             lnnum;			/* -n: add #line directives */
+static bool             symlist;		/* -s: output symbol list */
+static bool             symdepth;		/* -S: output symbol depth */
+static bool             text;			/* -t: this is a text file */
+
+static FILE            *input;			/* input file pointer */
+static const char      *filename;		/* input file name */
+static int              linenum;		/* current line number */
+static const char      *linefile;		/* file name for #line */
+static FILE            *output;			/* output file pointer */
+static const char      *ofilename;		/* output file name */
+static const char      *backext;		/* backup extension */
+static char            *tempname;		/* avoid splatting input */
+
+static char             tline[MAXLINE+EDITSLOP];/* input buffer plus space */
+static char            *keyword;		/* used for editing #elif's */
+
+/*
+ * When processing a file, the output's newline style will match the
+ * input's, and unifdef correctly handles CRLF or LF endings whatever
+ * the platform's native style. The stdio streams are opened in binary
+ * mode to accommodate platforms whose native newline style is CRLF.
+ * When the output isn't a processed input file (when it is error /
+ * debug / diagnostic messages) then unifdef uses native line endings.
+ */
+
+static const char      *newline;		/* input file format */
+static const char       newline_unix[] = "\n";
+static const char       newline_crlf[] = "\r\n";
+
+static Comment_state    incomment;		/* comment parser state */
+static Line_state       linestate;		/* #if line parser state */
+static Ifstate          ifstate[MAXDEPTH];	/* #if processor state */
+static bool             ignoring[MAXDEPTH];	/* ignore comments state */
+static int              stifline[MAXDEPTH];	/* start of current #if */
+static int              depth;			/* current #if nesting */
+static int              delcount;		/* count of deleted lines */
+static unsigned         blankcount;		/* count of blank lines */
+static unsigned         blankmax;		/* maximum recent blankcount */
+static bool             constexpr;		/* constant #if expression */
+static bool             zerosyms;		/* to format symdepth output */
+static bool             firstsym;		/* ditto */
+
+static int              exitmode;		/* exit status mode */
+static int              exitstat;		/* program exit status */
+static bool             altered;		/* was this file modified? */
+
+static void             addsym1(bool, bool, char *);
+static void             addsym2(bool, const char *, const char *);
+static char            *astrcat(const char *, const char *);
+static void             cleantemp(void);
+static void             closeio(void);
+static void             debug(const char *, ...);
+static void             debugsym(const char *, const struct macro *);
+static bool             defundef(void);
+static void             defundefile(const char *);
+static void             done(void);
+static void             error(const char *);
+static struct macro    *findsym(const char **);
+static void             flushline(bool);
+static void             hashline(void);
+static void             help(void);
+static Linetype         ifeval(const char **);
+static void             ignoreoff(void);
+static void             ignoreon(void);
+static void             indirectsym(void);
+static void             keywordedit(const char *);
+static const char      *matchsym(const char *, const char *);
+static void             nest(void);
+static Linetype         parseline(void);
+static void             process(void);
+static void             processinout(const char *, const char *);
+static const char      *skipargs(const char *);
+static const char      *skipcomment(const char *);
+static const char      *skiphash(void);
+static const char      *skipline(const char *);
+static const char      *skipsym(const char *);
+static void             state(Ifstate);
+static void             unnest(void);
+static void             usage(void);
+static void             version(void);
+static const char      *xstrdup(const char *, const char *);
+
+#define endsym(c) (!isalnum((unsigned char)c) && c != '_')
+
+/*
+ * The main program.
+ */
+int
+main(int argc, char *argv[])
+{
+	int opt;
+
+	while ((opt = getopt(argc, argv, "i:D:U:f:I:M:o:x:bBcdehKklmnsStV")) != -1)
+		switch (opt) {
+		case 'i': /* treat stuff controlled by these symbols as text */
+			/*
+			 * For strict backwards-compatibility the U or D
+			 * should be immediately after the -i but it doesn't
+			 * matter much if we relax that requirement.
+			 */
+			opt = *optarg++;
+			if (opt == 'D')
+				addsym1(true, true, optarg);
+			else if (opt == 'U')
+				addsym1(true, false, optarg);
+			else
+				usage();
+			break;
+		case 'D': /* define a symbol */
+			addsym1(false, true, optarg);
+			break;
+		case 'U': /* undef a symbol */
+			addsym1(false, false, optarg);
+			break;
+		case 'I': /* no-op for compatibility with cpp */
+			break;
+		case 'b': /* blank deleted lines instead of omitting them */
+		case 'l': /* backwards compatibility */
+			lnblank = true;
+			break;
+		case 'B': /* compress blank lines around removed section */
+			compblank = true;
+			break;
+		case 'c': /* treat -D as -U and vice versa */
+			complement = true;
+			break;
+		case 'd':
+			debugging = true;
+			break;
+		case 'e': /* fewer errors from dodgy lines */
+			iocccok = true;
+			break;
+		case 'f': /* definitions file */
+			defundefile(optarg);
+			break;
+		case 'h':
+			help();
+			break;
+		case 'K': /* keep ambiguous #ifs */
+			strictlogic = true;
+			break;
+		case 'k': /* process constant #ifs */
+			killconsts = true;
+			break;
+		case 'm': /* modify in place */
+			inplace = true;
+			break;
+		case 'M': /* modify in place and keep backup */
+			inplace = true;
+			if (strlen(optarg) > 0)
+				backext = optarg;
+			break;
+		case 'n': /* add #line directive after deleted lines */
+			lnnum = true;
+			break;
+		case 'o': /* output to a file */
+			ofilename = optarg;
+			break;
+		case 's': /* only output list of symbols that control #ifs */
+			symlist = true;
+			break;
+		case 'S': /* list symbols with their nesting depth */
+			symlist = symdepth = true;
+			break;
+		case 't': /* don't parse C comments */
+			text = true;
+			break;
+		case 'V':
+			version();
+			break;
+		case 'x':
+			exitmode = atoi(optarg);
+			if(exitmode < 0 || exitmode > 2)
+				usage();
+			break;
+		default:
+			usage();
+		}
+	argc -= optind;
+	argv += optind;
+	if (compblank && lnblank)
+		errx(2, "-B and -b are mutually exclusive");
+	if (symlist && (ofilename != NULL || inplace || argc > 1))
+		errx(2, "-s only works with one input file");
+	if (argc > 1 && ofilename != NULL)
+		errx(2, "-o cannot be used with multiple input files");
+	if (argc > 1 && !inplace)
+		errx(2, "multiple input files require -m or -M");
+	if (argc == 0 && inplace)
+		errx(2, "-m requires an input file");
+	if (argc == 0)
+		argc = 1;
+	if (argc == 1 && !inplace && ofilename == NULL)
+		ofilename = "-";
+	indirectsym();
+
+	atexit(cleantemp);
+	if (ofilename != NULL)
+		processinout(*argv, ofilename);
+	else while (argc-- > 0) {
+		processinout(*argv, *argv);
+		argv++;
+	}
+	switch(exitmode) {
+	case(0): exit(exitstat);
+	case(1): exit(!exitstat);
+	case(2): exit(0);
+	default: abort(); /* bug */
+	}
+}
+
+/*
+ * File logistics.
+ */
+static void
+processinout(const char *ifn, const char *ofn)
+{
+	struct stat st;
+
+	if (ifn == NULL || strcmp(ifn, "-") == 0) {
+		filename = "[stdin]";
+		linefile = NULL;
+		input = fbinmode(stdin);
+	} else {
+		filename = ifn;
+		linefile = ifn;
+		input = fopen(ifn, "rb");
+		if (input == NULL)
+			err(2, "can't open %s", ifn);
+	}
+	if (strcmp(ofn, "-") == 0) {
+		output = fbinmode(stdout);
+		process();
+		return;
+	}
+	if (stat(ofn, &st) < 0) {
+		output = fopen(ofn, "wb");
+		if (output == NULL)
+			err(2, "can't create %s", ofn);
+		process();
+		return;
+	}
+
+	tempname = astrcat(ofn, ".XXXXXX");
+	output = mktempmode(tempname, st.st_mode);
+	if (output == NULL)
+		err(2, "can't create %s", tempname);
+
+	process();
+
+	if (backext != NULL) {
+		char *backname = astrcat(ofn, backext);
+		if (rename(ofn, backname) < 0)
+			err(2, "can't rename \"%s\" to \"%s\"", ofn, backname);
+		free(backname);
+	}
+	/* leave file unmodified if unifdef made no changes */
+	if (!altered && backext == NULL) {
+		if (remove(tempname) < 0)
+			warn("can't remove \"%s\"", tempname);
+	} else if (replace(tempname, ofn) < 0)
+		err(2, "can't rename \"%s\" to \"%s\"", tempname, ofn);
+	free(tempname);
+	tempname = NULL;
+}
+
+/*
+ * For cleaning up if there is an error.
+ */
+static void
+cleantemp(void)
+{
+	if (tempname != NULL)
+		remove(tempname);
+}
+
+/*
+ * Self-identification functions.
+ */
+
+static void
+version(void)
+{
+	const char *c = copyright;
+	for (;;) {
+		while (*++c != '$')
+			if (*c == '\0')
+				exit(0);
+		while (*++c != '$')
+			putc(*c, stderr);
+		putc('\n', stderr);
+	}
+}
+
+static void
+synopsis(FILE *fp)
+{
+	fprintf(fp,
+	    "usage:	unifdef [-bBcdehKkmnsStV] [-x{012}] [-Mext] [-opath] \\\n"
+	    "		[-[i]Dsym[=val]] [-[i]Usym] [-fpath] ... [file] ...\n");
+}
+
+static void
+usage(void)
+{
+	synopsis(stderr);
+	exit(2);
+}
+
+static void
+help(void)
+{
+	synopsis(stdout);
+	printf(
+	    "	-Dsym=val  define preprocessor symbol with given value\n"
+	    "	-Dsym      define preprocessor symbol with value 1\n"
+	    "	-Usym	   preprocessor symbol is undefined\n"
+	    "	-iDsym=val \\  ignore C strings and comments\n"
+	    "	-iDsym      ) in sections controlled by these\n"
+	    "	-iUsym	   /  preprocessor symbols\n"
+	    "	-fpath	file containing #define and #undef directives\n"
+	    "	-b	blank lines instead of deleting them\n"
+	    "	-B	compress blank lines around deleted section\n"
+	    "	-c	complement (invert) keep vs. delete\n"
+	    "	-d	debugging mode\n"
+	    "	-e	ignore multiline preprocessor directives\n"
+	    "	-h	print help\n"
+	    "	-Ipath	extra include file path (ignored)\n"
+	    "	-K	disable && and || short-circuiting\n"
+	    "	-k	process constant #if expressions\n"
+	    "	-Mext	modify in place and keep backups\n"
+	    "	-m	modify input files in place\n"
+	    "	-n	add #line directives to output\n"
+	    "	-opath	output file name\n"
+	    "	-S	list #if control symbols with nesting\n"
+	    "	-s	list #if control symbols\n"
+	    "	-t	ignore C strings and comments\n"
+	    "	-V	print version\n"
+	    "	-x{012}	exit status mode\n"
+	);
+	exit(0);
+}
+
+/*
+ * A state transition function alters the global #if processing state
+ * in a particular way. The table below is indexed by the current
+ * processing state and the type of the current line.
+ *
+ * Nesting is handled by keeping a stack of states; some transition
+ * functions increase or decrease the depth. They also maintain the
+ * ignore state on a stack. In some complicated cases they have to
+ * alter the preprocessor directive, as follows.
+ *
+ * When we have processed a group that starts off with a known-false
+ * #if/#elif sequence (which has therefore been deleted) followed by a
+ * #elif that we don't understand and therefore must keep, we edit the
+ * latter into a #if to keep the nesting correct. We use memcpy() to
+ * overwrite the 4 byte token "elif" with "if  " without a '\0' byte.
+ *
+ * When we find a true #elif in a group, the following block will
+ * always be kept and the rest of the sequence after the next #elif or
+ * #else will be discarded. We edit the #elif into a #else and the
+ * following directive to #endif since this has the desired behaviour.
+ *
+ * "Dodgy" directives are split across multiple lines, the most common
+ * example being a multi-line comment hanging off the right of the
+ * directive. We can handle them correctly only if there is no change
+ * from printing to dropping (or vice versa) caused by that directive.
+ * If the directive is the first of a group we have a choice between
+ * failing with an error, or passing it through unchanged instead of
+ * evaluating it. The latter is not the default to avoid questions from
+ * users about unifdef unexpectedly leaving behind preprocessor directives.
+ */
+typedef void state_fn(void);
+
+/* report an error */
+static void Eelif (void) { error("Inappropriate #elif"); }
+static void Eelse (void) { error("Inappropriate #else"); }
+static void Eendif(void) { error("Inappropriate #endif"); }
+static void Eeof  (void) { error("Premature EOF"); }
+static void Eioccc(void) { error("Obfuscated preprocessor control line"); }
+/* plain line handling */
+static void print (void) { flushline(true); }
+static void drop  (void) { flushline(false); }
+/* output lacks group's start line */
+static void Strue (void) { drop();  ignoreoff(); state(IS_TRUE_PREFIX); }
+static void Sfalse(void) { drop();  ignoreoff(); state(IS_FALSE_PREFIX); }
+static void Selse (void) { drop();               state(IS_TRUE_ELSE); }
+/* print/pass this block */
+static void Pelif (void) { print(); ignoreoff(); state(IS_PASS_MIDDLE); }
+static void Pelse (void) { print();              state(IS_PASS_ELSE); }
+static void Pendif(void) { print(); unnest(); }
+/* discard this block */
+static void Dfalse(void) { drop();  ignoreoff(); state(IS_FALSE_TRAILER); }
+static void Delif (void) { drop();  ignoreoff(); state(IS_FALSE_MIDDLE); }
+static void Delse (void) { drop();               state(IS_FALSE_ELSE); }
+static void Dendif(void) { drop();  unnest(); }
+/* first line of group */
+static void Fdrop (void) { nest();  Dfalse(); }
+static void Fpass (void) { nest();  Pelif(); }
+static void Ftrue (void) { nest();  Strue(); }
+static void Ffalse(void) { nest();  Sfalse(); }
+/* variable pedantry for obfuscated lines */
+static void Oiffy (void) { if (!iocccok) Eioccc(); Fpass(); ignoreon(); }
+static void Oif   (void) { if (!iocccok) Eioccc(); Fpass(); }
+static void Oelif (void) { if (!iocccok) Eioccc(); Pelif(); }
+/* ignore comments in this block */
+static void Idrop (void) { Fdrop();  ignoreon(); }
+static void Itrue (void) { Ftrue();  ignoreon(); }
+static void Ifalse(void) { Ffalse(); ignoreon(); }
+/* modify this line */
+static void Mpass (void) { memcpy(keyword, "if  ", 4); Pelif(); }
+static void Mtrue (void) { keywordedit("else");  state(IS_TRUE_MIDDLE); }
+static void Melif (void) { keywordedit("endif"); state(IS_FALSE_TRAILER); }
+static void Melse (void) { keywordedit("endif"); state(IS_FALSE_ELSE); }
+
+static state_fn * const trans_table[IS_COUNT][LT_COUNT] = {
+/* IS_OUTSIDE */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Eendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Eelif, Eelif, Eelif, Eelse, Eendif,
+  print, done,  abort },
+/* IS_FALSE_PREFIX */
+{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Strue, Sfalse,Selse, Dendif,
+  Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Eioccc,Eioccc,Eioccc,Eioccc,
+  drop,  Eeof,  abort },
+/* IS_TRUE_PREFIX */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Dfalse,Dfalse,Dfalse,Delse, Dendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,
+  print, Eeof,  abort },
+/* IS_PASS_MIDDLE */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Pelif, Mtrue, Delif, Pelse, Pendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Pelif, Oelif, Oelif, Pelse, Pendif,
+  print, Eeof,  abort },
+/* IS_FALSE_MIDDLE */
+{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Pelif, Mtrue, Delif, Pelse, Pendif,
+  Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,
+  drop,  Eeof,  abort },
+/* IS_TRUE_MIDDLE */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Melif, Melif, Melif, Melse, Pendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Eioccc,Eioccc,Eioccc,Eioccc,Pendif,
+  print, Eeof,  abort },
+/* IS_PASS_ELSE */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Pendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Eelif, Eelif, Eelif, Eelse, Pendif,
+  print, Eeof,  abort },
+/* IS_FALSE_ELSE */
+{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Dendif,
+  Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Eioccc,
+  drop,  Eeof,  abort },
+/* IS_TRUE_ELSE */
+{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Dendif,
+  Oiffy, Oiffy, Fpass, Oif,   Oif,   Eelif, Eelif, Eelif, Eelse, Eioccc,
+  print, Eeof,  abort },
+/* IS_FALSE_TRAILER */
+{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Dendif,
+  Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Eioccc,
+  drop,  Eeof,  abort }
+/*TRUEI  FALSEI IF     TRUE   FALSE  ELIF   ELTRUE ELFALSE ELSE  ENDIF
+  TRUEI  FALSEI IF     TRUE   FALSE  ELIF   ELTRUE ELFALSE ELSE  ENDIF (DODGY)
+  PLAIN  EOF    ERROR */
+};
+
+/*
+ * State machine utility functions
+ */
+static void
+ignoreoff(void)
+{
+	if (depth == 0)
+		abort(); /* bug */
+	ignoring[depth] = ignoring[depth-1];
+}
+static void
+ignoreon(void)
+{
+	ignoring[depth] = true;
+}
+static void
+keywordedit(const char *replacement)
+{
+	snprintf(keyword, tline + sizeof(tline) - keyword,
+	    "%s%s", replacement, newline);
+	altered = true;
+	print();
+}
+static void
+nest(void)
+{
+	if (depth > MAXDEPTH-1)
+		abort(); /* bug */
+	if (depth == MAXDEPTH-1)
+		error("Too many levels of nesting");
+	depth += 1;
+	stifline[depth] = linenum;
+}
+static void
+unnest(void)
+{
+	if (depth == 0)
+		abort(); /* bug */
+	depth -= 1;
+}
+static void
+state(Ifstate is)
+{
+	ifstate[depth] = is;
+}
+
+/*
+ * The last state transition function. When this is called,
+ * lineval == LT_EOF, so the process() loop will terminate.
+ */
+static void
+done(void)
+{
+	if (incomment)
+		error("EOF in comment");
+	closeio();
+}
+
+/*
+ * Write a line to the output or not, according to command line options.
+ * If writing fails, closeio() will print the error and exit.
+ */
+static void
+flushline(bool keep)
+{
+	if (symlist)
+		return;
+	if (keep ^ complement) {
+		bool blankline = tline[strspn(tline, " \t\r\n")] == '\0';
+		if (blankline && compblank && blankcount != blankmax) {
+			delcount += 1;
+			blankcount += 1;
+		} else {
+			if (lnnum && delcount > 0)
+				hashline();
+			if (fputs(tline, output) == EOF)
+				closeio();
+			delcount = 0;
+			blankmax = blankcount = blankline ? blankcount + 1 : 0;
+		}
+	} else {
+		if (lnblank && fputs(newline, output) == EOF)
+			closeio();
+		altered = true;
+		delcount += 1;
+		blankcount = 0;
+	}
+	if (debugging && fflush(output) == EOF)
+		closeio();
+}
+
+/*
+ * Format of #line directives depends on whether we know the input filename.
+ */
+static void
+hashline(void)
+{
+	int e;
+
+	if (linefile == NULL)
+		e = fprintf(output, "#line %d%s", linenum, newline);
+	else
+		e = fprintf(output, "#line %d \"%s\"%s",
+		    linenum, linefile, newline);
+	if (e < 0)
+		closeio();
+}
+
+/*
+ * Flush the output and handle errors.
+ */
+static void
+closeio(void)
+{
+	/* Tidy up after findsym(). */
+	if (symdepth && !zerosyms)
+		printf("\n");
+	if (output != NULL && (ferror(output) || fclose(output) == EOF))
+			err(2, "%s: can't write to output", filename);
+	fclose(input);
+}
+
+/*
+ * The driver for the state machine.
+ */
+static void
+process(void)
+{
+	Linetype lineval = LT_PLAIN;
+	/* When compressing blank lines, act as if the file
+	   is preceded by a large number of blank lines. */
+	blankmax = blankcount = 1000;
+	zerosyms = true;
+	newline = NULL;
+	linenum = 0;
+	altered = false;
+	while (lineval != LT_EOF) {
+		lineval = parseline();
+		trans_table[ifstate[depth]][lineval]();
+		debug("process line %d %s -> %s depth %d",
+		    linenum, linetype_name[lineval],
+		    ifstate_name[ifstate[depth]], depth);
+	}
+	exitstat |= altered;
+}
+
+/*
+ * Parse a line and determine its type. We keep the preprocessor line
+ * parser state between calls in the global variable linestate, with
+ * help from skipcomment().
+ */
+static Linetype
+parseline(void)
+{
+	const char *cp;
+	struct macro *cursym;
+	Linetype retval;
+	Comment_state wascomment;
+
+	wascomment = incomment;
+	cp = skiphash();
+	if (cp == NULL)
+		return (LT_EOF);
+	if (newline == NULL) {
+		if (strrchr(tline, '\n') == strrchr(tline, '\r') + 1)
+			newline = newline_crlf;
+		else
+			newline = newline_unix;
+	}
+	if (*cp == '\0') {
+		retval = LT_PLAIN;
+		goto done;
+	}
+	keyword = tline + (cp - tline);
+	if ((cp = matchsym("ifdef", keyword)) != NULL ||
+	    (cp = matchsym("ifndef", keyword)) != NULL) {
+		cp = skipcomment(cp);
+		if ((cursym = findsym(&cp)) == NULL)
+			retval = LT_IF;
+		else {
+			retval = (keyword[2] == 'n')
+			    ? LT_FALSE : LT_TRUE;
+			if (cursym->value == NULL)
+				retval = (retval == LT_TRUE)
+				    ? LT_FALSE : LT_TRUE;
+			if (cursym->ignore)
+				retval = (retval == LT_TRUE)
+				    ? LT_TRUEI : LT_FALSEI;
+		}
+	} else if ((cp = matchsym("if", keyword)) != NULL)
+		retval = ifeval(&cp);
+	else if ((cp = matchsym("elif", keyword)) != NULL)
+		retval = linetype_if2elif(ifeval(&cp));
+	else if ((cp = matchsym("else", keyword)) != NULL)
+		retval = LT_ELSE;
+	else if ((cp = matchsym("endif", keyword)) != NULL)
+		retval = LT_ENDIF;
+	else {
+		cp = skipsym(keyword);
+		/* no way can we deal with a continuation inside a keyword */
+		if (strncmp(cp, "\\\r\n", 3) == 0 ||
+		    strncmp(cp, "\\\n", 2) == 0)
+			Eioccc();
+		cp = skipline(cp);
+		retval = LT_PLAIN;
+		goto done;
+	}
+	cp = skipcomment(cp);
+	if (*cp != '\0') {
+		cp = skipline(cp);
+		if (retval == LT_TRUE || retval == LT_FALSE ||
+		    retval == LT_TRUEI || retval == LT_FALSEI)
+			retval = LT_IF;
+		if (retval == LT_ELTRUE || retval == LT_ELFALSE)
+			retval = LT_ELIF;
+	}
+	/* the following can happen if the last line of the file lacks a
+	   newline or if there is too much whitespace in a directive */
+	if (linestate == LS_HASH) {
+		long len = cp - tline;
+		if (fgets(tline + len, MAXLINE - len, input) == NULL) {
+			if (ferror(input))
+				err(2, "can't read %s", filename);
+			debug("parser insert newline at EOF", linenum);
+			strcpy(tline + len, newline);
+			cp += strlen(newline);
+			linestate = LS_START;
+		} else {
+			debug("parser concatenate dangling whitespace");
+			++linenum;
+			cp = skipcomment(cp);
+		}
+	}
+	if (retval != LT_PLAIN && (wascomment || linestate != LS_START)) {
+		retval = linetype_2dodgy(retval);
+		linestate = LS_DIRTY;
+	}
+done:
+	debug("parser line %d state %s comment %s line", linenum,
+	    comment_name[incomment], linestate_name[linestate]);
+	return (retval);
+}
+
+/*
+ * These are the binary operators that are supported by the expression
+ * evaluator.
+ */
+static Linetype op_strict(long *p, long v, Linetype at, Linetype bt) {
+	if(at == LT_IF || bt == LT_IF) return (LT_IF);
+	return (*p = v, v ? LT_TRUE : LT_FALSE);
+}
+static Linetype op_lt(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a < b, at, bt);
+}
+static Linetype op_gt(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a > b, at, bt);
+}
+static Linetype op_le(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a <= b, at, bt);
+}
+static Linetype op_ge(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a >= b, at, bt);
+}
+static Linetype op_eq(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a == b, at, bt);
+}
+static Linetype op_ne(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a != b, at, bt);
+}
+static Linetype op_or(long *p, Linetype at, long a, Linetype bt, long b) {
+	if (!strictlogic && (at == LT_TRUE || bt == LT_TRUE))
+		return (*p = 1, LT_TRUE);
+	return op_strict(p, a || b, at, bt);
+}
+static Linetype op_and(long *p, Linetype at, long a, Linetype bt, long b) {
+	if (!strictlogic && (at == LT_FALSE || bt == LT_FALSE))
+		return (*p = 0, LT_FALSE);
+	return op_strict(p, a && b, at, bt);
+}
+static Linetype op_blsh(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a << b, at, bt);
+}
+static Linetype op_brsh(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a >> b, at, bt);
+}
+static Linetype op_add(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a + b, at, bt);
+}
+static Linetype op_sub(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a - b, at, bt);
+}
+static Linetype op_mul(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a * b, at, bt);
+}
+static Linetype op_div(long *p, Linetype at, long a, Linetype bt, long b) {
+	if (bt != LT_TRUE) {
+		debug("eval division by zero");
+		return (LT_ERROR);
+	}
+	return op_strict(p, a / b, at, bt);
+}
+static Linetype op_mod(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a % b, at, bt);
+}
+static Linetype op_bor(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a | b, at, bt);
+}
+static Linetype op_bxor(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a ^ b, at, bt);
+}
+static Linetype op_band(long *p, Linetype at, long a, Linetype bt, long b) {
+	return op_strict(p, a & b, at, bt);
+}
+
+/*
+ * An evaluation function takes three arguments, as follows: (1) a pointer to
+ * an element of the precedence table which lists the operators at the current
+ * level of precedence; (2) a pointer to an integer which will receive the
+ * value of the expression; and (3) a pointer to a char* that points to the
+ * expression to be evaluated and that is updated to the end of the expression
+ * when evaluation is complete. The function returns LT_FALSE if the value of
+ * the expression is zero, LT_TRUE if it is non-zero, LT_IF if the expression
+ * depends on an unknown symbol, or LT_ERROR if there is a parse failure.
+ */
+struct ops;
+
+typedef Linetype eval_fn(const struct ops *, long *, const char **);
+
+static eval_fn eval_table, eval_unary;
+
+/*
+ * The precedence table. Expressions involving binary operators are evaluated
+ * in a table-driven way by eval_table. When it evaluates a subexpression it
+ * calls the inner function with its first argument pointing to the next
+ * element of the table. Innermost expressions have special non-table-driven
+ * handling.
+ *
+ * The stop characters help with lexical analysis: an operator is not
+ * recognized if it is followed by one of the stop characters because
+ * that would make it a different operator.
+ */
+struct op {
+	const char *str;
+	Linetype (*fn)(long *, Linetype, long, Linetype, long);
+	const char *stop;
+};
+struct ops {
+	eval_fn *inner;
+	struct op op[5];
+};
+static const struct ops eval_ops[] = {
+	{ eval_table, { { "||", op_or,   NULL } } },
+	{ eval_table, { { "&&", op_and,  NULL } } },
+	{ eval_table, { { "|",  op_bor,  "|" } } },
+	{ eval_table, { { "^",  op_bxor, NULL } } },
+	{ eval_table, { { "&",  op_band, "&" } } },
+	{ eval_table, { { "==", op_eq,   NULL },
+			{ "!=", op_ne,   NULL } } },
+	{ eval_table, { { "<=", op_le,   NULL },
+			{ ">=", op_ge,   NULL },
+			{ "<",  op_lt,   "<=" },
+			{ ">",  op_gt,   ">=" } } },
+	{ eval_table, { { "<<", op_blsh, NULL },
+			{ ">>", op_brsh, NULL } } },
+	{ eval_table, { { "+",  op_add,  NULL },
+			{ "-",  op_sub,  NULL } } },
+	{ eval_unary, { { "*",  op_mul,  NULL },
+			{ "/",  op_div,  NULL },
+			{ "%",  op_mod,  NULL } } },
+};
+
+/* Current operator precedence level */
+static long prec(const struct ops *ops)
+{
+	return (ops - eval_ops);
+}
+
+/*
+ * Function for evaluating the innermost parts of expressions,
+ * viz. !expr (expr) number defined(symbol) symbol
+ * We reset the constexpr flag in the last two cases.
+ */
+static Linetype
+eval_unary(const struct ops *ops, long *valp, const char **cpp)
+{
+	const char *cp;
+	char *ep;
+	struct macro *sym;
+	bool defparen;
+	Linetype lt;
+
+	cp = skipcomment(*cpp);
+	if (*cp == '!') {
+		debug("eval%d !", prec(ops));
+		cp++;
+		lt = eval_unary(ops, valp, &cp);
+		if (lt == LT_ERROR)
+			return (LT_ERROR);
+		if (lt != LT_IF) {
+			*valp = !*valp;
+			lt = *valp ? LT_TRUE : LT_FALSE;
+		}
+	} else if (*cp == '~') {
+		debug("eval%d ~", prec(ops));
+		cp++;
+		lt = eval_unary(ops, valp, &cp);
+		if (lt == LT_ERROR)
+			return (LT_ERROR);
+		if (lt != LT_IF) {
+			*valp = ~(*valp);
+			lt = *valp ? LT_TRUE : LT_FALSE;
+		}
+	} else if (*cp == '-') {
+		debug("eval%d -", prec(ops));
+		cp++;
+		lt = eval_unary(ops, valp, &cp);
+		if (lt == LT_ERROR)
+			return (LT_ERROR);
+		if (lt != LT_IF) {
+			*valp = -(*valp);
+			lt = *valp ? LT_TRUE : LT_FALSE;
+		}
+	} else if (*cp == '(') {
+		cp++;
+		debug("eval%d (", prec(ops));
+		lt = eval_table(eval_ops, valp, &cp);
+		if (lt == LT_ERROR)
+			return (LT_ERROR);
+		cp = skipcomment(cp);
+		if (*cp++ != ')')
+			return (LT_ERROR);
+	} else if (isdigit((unsigned char)*cp)) {
+		debug("eval%d number", prec(ops));
+		*valp = strtol(cp, &ep, 0);
+		if (ep == cp)
+			return (LT_ERROR);
+		lt = *valp ? LT_TRUE : LT_FALSE;
+		cp = ep;
+	} else if (matchsym("defined", cp) != NULL) {
+		cp = skipcomment(cp+7);
+		if (*cp == '(') {
+			cp = skipcomment(cp+1);
+			defparen = true;
+		} else {
+			defparen = false;
+		}
+		sym = findsym(&cp);
+		cp = skipcomment(cp);
+		if (defparen && *cp++ != ')') {
+			debug("eval%d defined missing ')'", prec(ops));
+			return (LT_ERROR);
+		}
+		if (sym == NULL) {
+			debug("eval%d defined unknown", prec(ops));
+			lt = LT_IF;
+		} else {
+			debug("eval%d defined %s", prec(ops), sym->name);
+			*valp = (sym->value != NULL);
+			lt = *valp ? LT_TRUE : LT_FALSE;
+		}
+		constexpr = false;
+	} else if (!endsym(*cp)) {
+		debug("eval%d symbol", prec(ops));
+		sym = findsym(&cp);
+		if (sym == NULL) {
+			lt = LT_IF;
+			cp = skipargs(cp);
+		} else if (sym->value == NULL) {
+			*valp = 0;
+			lt = LT_FALSE;
+		} else {
+			*valp = strtol(sym->value, &ep, 0);
+			if (*ep != '\0' || ep == sym->value)
+				return (LT_ERROR);
+			lt = *valp ? LT_TRUE : LT_FALSE;
+			cp = skipargs(cp);
+		}
+		constexpr = false;
+	} else {
+		debug("eval%d bad expr", prec(ops));
+		return (LT_ERROR);
+	}
+
+	*cpp = cp;
+	debug("eval%d = %d", prec(ops), *valp);
+	return (lt);
+}
+
+/*
+ * Table-driven evaluation of binary operators.
+ */
+static Linetype
+eval_table(const struct ops *ops, long *valp, const char **cpp)
+{
+	const struct op *op;
+	const char *cp;
+	long val = 0;
+	Linetype lt, rt;
+
+	debug("eval%d", prec(ops));
+	cp = *cpp;
+	lt = ops->inner(ops+1, valp, &cp);
+	if (lt == LT_ERROR)
+		return (LT_ERROR);
+	for (;;) {
+		cp = skipcomment(cp);
+		for (op = ops->op; op->str != NULL; op++) {
+			if (strncmp(cp, op->str, strlen(op->str)) == 0) {
+				/* assume only one-char operators have stop chars */
+				if (op->stop != NULL && cp[1] != '\0' &&
+				    strchr(op->stop, cp[1]) != NULL)
+					continue;
+				else
+					break;
+			}
+		}
+		if (op->str == NULL)
+			break;
+		cp += strlen(op->str);
+		debug("eval%d %s", prec(ops), op->str);
+		rt = ops->inner(ops+1, &val, &cp);
+		if (rt == LT_ERROR)
+			return (LT_ERROR);
+		lt = op->fn(valp, lt, *valp, rt, val);
+	}
+
+	*cpp = cp;
+	debug("eval%d = %d", prec(ops), *valp);
+	debug("eval%d lt = %s", prec(ops), linetype_name[lt]);
+	return (lt);
+}
+
+/*
+ * Evaluate the expression on a #if or #elif line. If we can work out
+ * the result we return LT_TRUE or LT_FALSE accordingly, otherwise we
+ * return just a generic LT_IF.
+ */
+static Linetype
+ifeval(const char **cpp)
+{
+	Linetype ret;
+	long val = 0;
+
+	debug("eval %s", *cpp);
+	constexpr = killconsts ? false : true;
+	ret = eval_table(eval_ops, &val, cpp);
+	debug("eval = %d", val);
+	return (constexpr ? LT_IF : ret == LT_ERROR ? LT_IF : ret);
+}
+
+/*
+ * Read a line and examine its initial part to determine if it is a
+ * preprocessor directive. Returns NULL on EOF, or a pointer to a
+ * preprocessor directive name, or a pointer to the zero byte at the
+ * end of the line.
+ */
+static const char *
+skiphash(void)
+{
+	const char *cp;
+
+	linenum++;
+	if (fgets(tline, MAXLINE, input) == NULL) {
+		if (ferror(input))
+			err(2, "can't read %s", filename);
+		else
+			return (NULL);
+	}
+	cp = skipcomment(tline);
+	if (linestate == LS_START && *cp == '#') {
+		linestate = LS_HASH;
+		return (skipcomment(cp + 1));
+	} else if (*cp == '\0') {
+		return (cp);
+	} else {
+		return (skipline(cp));
+	}
+}
+
+/*
+ * Mark a line dirty and consume the rest of it, keeping track of the
+ * lexical state.
+ */
+static const char *
+skipline(const char *cp)
+{
+	const char *pcp;
+	if (*cp != '\0')
+		linestate = LS_DIRTY;
+	while (*cp != '\0') {
+		cp = skipcomment(pcp = cp);
+		if (pcp == cp)
+			cp++;
+	}
+	return (cp);
+}
+
+/*
+ * Skip over comments, strings, and character literals and stop at the
+ * next character position that is not whitespace. Between calls we keep
+ * the comment state in the global variable incomment, and we also adjust
+ * the global variable linestate when we see a newline.
+ * XXX: doesn't cope with the buffer splitting inside a state transition.
+ */
+static const char *
+skipcomment(const char *cp)
+{
+	if (text || ignoring[depth]) {
+		for (; isspace((unsigned char)*cp); cp++)
+			if (*cp == '\n')
+				linestate = LS_START;
+		return (cp);
+	}
+	while (*cp != '\0')
+		/* don't reset to LS_START after a line continuation */
+		if (strncmp(cp, "\\\r\n", 3) == 0)
+			cp += 3;
+		else if (strncmp(cp, "\\\n", 2) == 0)
+			cp += 2;
+		else switch (incomment) {
+		case NO_COMMENT:
+			if (strncmp(cp, "/\\\r\n", 4) == 0) {
+				incomment = STARTING_COMMENT;
+				cp += 4;
+			} else if (strncmp(cp, "/\\\n", 3) == 0) {
+				incomment = STARTING_COMMENT;
+				cp += 3;
+			} else if (strncmp(cp, "/*", 2) == 0) {
+				incomment = C_COMMENT;
+				cp += 2;
+			} else if (strncmp(cp, "//", 2) == 0) {
+				incomment = CXX_COMMENT;
+				cp += 2;
+			} else if (strncmp(cp, "\'", 1) == 0) {
+				incomment = CHAR_LITERAL;
+				linestate = LS_DIRTY;
+				cp += 1;
+			} else if (strncmp(cp, "\"", 1) == 0) {
+				incomment = STRING_LITERAL;
+				linestate = LS_DIRTY;
+				cp += 1;
+			} else if (strncmp(cp, "R\"(", 3) == 0) {
+				incomment = RAW_STRING_LITERAL;
+				linestate = LS_DIRTY;
+				cp += 3;
+			} else if (strncmp(cp, "\n", 1) == 0) {
+				linestate = LS_START;
+				cp += 1;
+			} else if (strchr(" \r\t", *cp) != NULL) {
+				cp += 1;
+			} else
+				return (cp);
+			continue;
+		case CXX_COMMENT:
+			if (strncmp(cp, "\n", 1) == 0) {
+				incomment = NO_COMMENT;
+				linestate = LS_START;
+			}
+			cp += 1;
+			continue;
+		case CHAR_LITERAL:
+		case STRING_LITERAL:
+			if ((incomment == CHAR_LITERAL && cp[0] == '\'') ||
+			    (incomment == STRING_LITERAL && cp[0] == '\"')) {
+				incomment = NO_COMMENT;
+				cp += 1;
+			} else if (cp[0] == '\\') {
+				if (cp[1] == '\0')
+					cp += 1;
+				else
+					cp += 2;
+			} else if (strncmp(cp, "\n", 1) == 0) {
+				if (incomment == CHAR_LITERAL)
+					error("Unterminated char literal");
+				else
+					error("Unterminated string literal");
+			} else
+				cp += 1;
+			continue;
+		case RAW_STRING_LITERAL:
+			if (strncmp(cp, ")\"", 2) == 0) {
+				incomment = NO_COMMENT;
+				cp += 2;
+			} else
+				cp += 1;
+			continue;
+		case C_COMMENT:
+			if (strncmp(cp, "*\\\r\n", 4) == 0) {
+				incomment = FINISHING_COMMENT;
+				cp += 4;
+			} else if (strncmp(cp, "*\\\n", 3) == 0) {
+				incomment = FINISHING_COMMENT;
+				cp += 3;
+			} else if (strncmp(cp, "*/", 2) == 0) {
+				incomment = NO_COMMENT;
+				cp += 2;
+			} else
+				cp += 1;
+			continue;
+		case STARTING_COMMENT:
+			if (*cp == '*') {
+				incomment = C_COMMENT;
+				cp += 1;
+			} else if (*cp == '/') {
+				incomment = CXX_COMMENT;
+				cp += 1;
+			} else {
+				incomment = NO_COMMENT;
+				linestate = LS_DIRTY;
+			}
+			continue;
+		case FINISHING_COMMENT:
+			if (*cp == '/') {
+				incomment = NO_COMMENT;
+				cp += 1;
+			} else
+				incomment = C_COMMENT;
+			continue;
+		default:
+			abort(); /* bug */
+		}
+	return (cp);
+}
+
+/*
+ * Skip macro arguments.
+ */
+static const char *
+skipargs(const char *cp)
+{
+	const char *ocp = cp;
+	int level = 0;
+	cp = skipcomment(cp);
+	if (*cp != '(')
+		return (cp);
+	do {
+		if (*cp == '(')
+			level++;
+		if (*cp == ')')
+			level--;
+		cp = skipcomment(cp+1);
+	} while (level != 0 && *cp != '\0');
+	if (level == 0)
+		return (cp);
+	else
+	/* Rewind and re-detect the syntax error later. */
+		return (ocp);
+}
+
+/*
+ * Skip over an identifier.
+ */
+static const char *
+skipsym(const char *cp)
+{
+	while (!endsym(*cp))
+		++cp;
+	return (cp);
+}
+
+/*
+ * Skip whitespace and take a copy of any following identifier.
+ */
+static const char *
+getsym(const char **cpp)
+{
+	const char *cp = *cpp, *sym;
+
+	cp = skipcomment(cp);
+	cp = skipsym(sym = cp);
+	if (cp == sym)
+		return NULL;
+	*cpp = cp;
+	return (xstrdup(sym, cp));
+}
+
+/*
+ * Check that s (a symbol) matches the start of t, and that the
+ * following character in t is not a symbol character. Returns a
+ * pointer to the following character in t if there is a match,
+ * otherwise NULL.
+ */
+static const char *
+matchsym(const char *s, const char *t)
+{
+	while (*s != '\0' && *t != '\0')
+		if (*s != *t)
+			return (NULL);
+		else
+			++s, ++t;
+	if (*s == '\0' && endsym(*t))
+		return(t);
+	else
+		return(NULL);
+}
+
+/*
+ * Look for the symbol in the symbol table. If it is found, we return
+ * the symbol table index, else we return -1.
+ */
+static struct macro *
+findsym(const char **strp)
+{
+	const char *str;
+	char *strkey;
+	struct macro key, *res;
+
+	str = *strp;
+	*strp = skipsym(str);
+	if (symlist) {
+		if (*strp == str)
+			return (NULL);
+		if (symdepth && firstsym)
+			printf("%s%3d", zerosyms ? "" : "\n", depth);
+		firstsym = zerosyms = false;
+		printf("%s%.*s%s",
+		       symdepth ? " " : "",
+		       (int)(*strp-str), str,
+		       symdepth ? "" : "\n");
+		/* we don't care about the value of the symbol */
+		return (NULL);
+	}
+
+	/*
+	 * 'str' just points into the current mid-parse input and is not
+	 * nul-terminated.  We know the length of the symbol, *strp - str, but
+	 * need to provide a nul-terminated lookup key for RB_FIND's comparison
+	 * function.  Create one here.
+	 */
+	strkey = malloc(*strp - str + 1);
+	memcpy(strkey, str, *strp - str);
+	strkey[*strp - str] = 0;
+
+	key.name = strkey;
+	res = RB_FIND(MACROMAP, &macro_tree, &key);
+	if (res != NULL)
+		debugsym("findsym", res);
+
+	free(strkey);
+	return (res);
+}
+
+/*
+ * Resolve indirect symbol values to their final definitions.
+ */
+static void
+indirectsym(void)
+{
+	const char *cp;
+	int changed;
+	struct macro *sym, *ind;
+
+	do {
+		changed = 0;
+		RB_FOREACH(sym, MACROMAP, &macro_tree) {
+			if (sym->value == NULL)
+				continue;
+			cp = sym->value;
+			ind = findsym(&cp);
+			if (ind == NULL || ind == sym ||
+			    *cp != '\0' ||
+			    ind->value == NULL ||
+			    ind->value == sym->value)
+				continue;
+			debugsym("indir...", sym);
+			sym->value = ind->value;
+			debugsym("...ectsym", sym);
+			changed++;
+		}
+	} while (changed);
+}
+
+/*
+ * Add a symbol to the symbol table, specified with the format sym=val
+ */
+static void
+addsym1(bool ignorethis, bool definethis, char *symval)
+{
+	const char *sym, *val;
+
+	sym = symval;
+	val = skipsym(sym);
+	if (definethis && *val == '=') {
+		symval[val - sym] = '\0';
+		val = val + 1;
+	} else if (*val == '\0') {
+		val = definethis ? "1" : NULL;
+	} else {
+		usage();
+	}
+	addsym2(ignorethis, sym, val);
+}
+
+/*
+ * Add a symbol to the symbol table.
+ */
+static void
+addsym2(bool ignorethis, const char *symname, const char *val)
+{
+	const char *cp = symname;
+	struct macro *sym, *r;
+
+	sym = findsym(&cp);
+	if (sym == NULL) {
+		sym = calloc(1, sizeof(*sym));
+		sym->ignore = ignorethis;
+		sym->name = symname;
+		sym->value = val;
+		r = RB_INSERT(MACROMAP, &macro_tree, sym);
+		assert(r == NULL);
+	}
+	debugsym("addsym", sym);
+}
+
+static void
+debugsym(const char *why, const struct macro *sym)
+{
+	debug("%s %s%c%s", why, sym->name,
+	    sym->value ? '=' : ' ',
+	    sym->value ? sym->value : "undef");
+}
+
+/*
+ * Add symbols to the symbol table from a file containing
+ * #define and #undef preprocessor directives.
+ */
+static void
+defundefile(const char *fn)
+{
+	filename = fn;
+	input = fopen(fn, "rb");
+	if (input == NULL)
+		err(2, "can't open %s", fn);
+	linenum = 0;
+	while (defundef())
+		;
+	if (ferror(input))
+		err(2, "can't read %s", filename);
+	else
+		fclose(input);
+	if (incomment)
+		error("EOF in comment");
+}
+
+/*
+ * Read and process one #define or #undef directive
+ */
+static bool
+defundef(void)
+{
+	const char *cp, *kw, *sym, *val, *end;
+
+	cp = skiphash();
+	if (cp == NULL)
+		return (false);
+	if (*cp == '\0')
+		goto done;
+	/* strip trailing whitespace, and do a fairly rough check to
+	   avoid unsupported multi-line preprocessor directives */
+	end = cp + strlen(cp);
+	while (end > tline && strchr(" \t\n\r", end[-1]) != NULL)
+		--end;
+	if (end > tline && end[-1] == '\\')
+		Eioccc();
+
+	kw = cp;
+	if ((cp = matchsym("define", kw)) != NULL) {
+		sym = getsym(&cp);
+		if (sym == NULL)
+			error("Missing macro name in #define");
+		if (*cp == '(') {
+			val = "1";
+		} else {
+			cp = skipcomment(cp);
+			val = (cp < end) ? xstrdup(cp, end) : "";
+		}
+		debug("#define");
+		addsym2(false, sym, val);
+	} else if ((cp = matchsym("undef", kw)) != NULL) {
+		sym = getsym(&cp);
+		if (sym == NULL)
+			error("Missing macro name in #undef");
+		cp = skipcomment(cp);
+		debug("#undef");
+		addsym2(false, sym, NULL);
+	} else {
+		error("Unrecognized preprocessor directive");
+	}
+	skipline(cp);
+done:
+	debug("parser line %d state %s comment %s line", linenum,
+	    comment_name[incomment], linestate_name[linestate]);
+	return (true);
+}
+
+/*
+ * Concatenate two strings into new memory, checking for failure.
+ */
+static char *
+astrcat(const char *s1, const char *s2)
+{
+	char *s;
+	int len;
+	size_t size;
+
+	len = snprintf(NULL, 0, "%s%s", s1, s2);
+	if (len < 0)
+		err(2, "snprintf");
+	size = (size_t)len + 1;
+	s = (char *)malloc(size);
+	if (s == NULL)
+		err(2, "malloc");
+	snprintf(s, size, "%s%s", s1, s2);
+	return (s);
+}
+
+/*
+ * Duplicate a segment of a string, checking for failure.
+ */
+static const char *
+xstrdup(const char *start, const char *end)
+{
+	size_t n;
+	char *s;
+
+	if (end < start) abort(); /* bug */
+	n = (size_t)(end - start) + 1;
+	s = (char *)malloc(n);
+	if (s == NULL)
+		err(2, "malloc");
+	snprintf(s, n, "%s", start);
+	return (s);
+}
+
+/*
+ * Diagnostics.
+ */
+static void
+debug(const char *msg, ...)
+{
+	va_list ap;
+
+	if (debugging) {
+		va_start(ap, msg);
+		vwarnx(msg, ap);
+		va_end(ap);
+	}
+}
+
+static void
+error(const char *msg)
+{
+	if (depth == 0)
+		warnx("%s: %d: %s", filename, linenum, msg);
+	else
+		warnx("%s: %d: %s (#if line %d depth %d)",
+		    filename, linenum, msg, stifline[depth], depth);
+	closeio();
+	errx(2, "Output may be truncated");
+}
diff --git a/contrib/unifdef/unifdef.h b/contrib/unifdef/unifdef.h
new file mode 100644
index 000000000000..b785129406c9
--- /dev/null
+++ b/contrib/unifdef/unifdef.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2012 - 2013 Tony Finch <dot@dotat.at>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/tree.h>
+
+#include <assert.h>
+#include <ctype.h>
+#include <err.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/* portability stubs */
+
+#define fbinmode(fp) (fp)
+
+#define replace(old,new) rename(old,new)
+
+static FILE *
+mktempmode(char *tmp, int mode)
+{
+	int fd = mkstemp(tmp);
+	if (fd < 0) return (NULL);
+	fchmod(fd, mode & (S_IRWXU|S_IRWXG|S_IRWXO));
+	return (fdopen(fd, "wb"));
+}
diff --git a/contrib/unifdef/unifdefall.sh b/contrib/unifdef/unifdefall.sh
new file mode 100755
index 000000000000..0755d9fb719f
--- /dev/null
+++ b/contrib/unifdef/unifdefall.sh
@@ -0,0 +1,58 @@
+#!/bin/sh
+#
+# unifdefall: remove all the #if's from a source file
+#
+# Copyright (c) 2002 - 2013 Tony Finch <dot@dotat.at>
+# Copyright (c) 2009 - 2010 Jonathan Nieder <jrnieder@gmail.com>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+set -e
+
+unifdef="$(dirname "$0")/unifdef"
+if [ ! -e "$unifdef" ]
+then
+	unifdef=unifdef
+fi
+
+case "$@" in
+"-d "*)	echo DEBUGGING 1>&2
+	debug=-d
+	shift
+esac
+
+tmp=$(mktemp -d "${TMPDIR:-/tmp}/${0##*/}.XXXXXXXXXX") || exit 2
+trap 'rm -r "$tmp" || exit 2' EXIT
+
+export LC_ALL=C
+
+# list of all controlling macros; assume these are undefined
+"$unifdef" $debug -s "$@" | sort -u | sed 's/^/#undef /' >"$tmp/undefs"
+# list of all macro definitions
+cc -E -dM "$@" | sort >"$tmp/defs"
+
+case $debug in
+-d)	cat "$tmp/undefs" "$tmp/defs" 1>&2
+esac
+
+# order of -f arguments means definitions override undefs
+"$unifdef" $debug -k -f "$tmp/undefs" -f "$tmp/defs" "$@"
diff --git a/contrib/unifdef/version.h b/contrib/unifdef/version.h
new file mode 100644
index 000000000000..28ab8595949c
--- /dev/null
+++ b/contrib/unifdef/version.h
@@ -0,0 +1,2 @@
+"@(#) $Version: unifdef-2.12 $\n"
+"@(#) $Date: 2020-02-14 16:37:16 +0000 $\n"
diff --git a/contrib/unifdef/win32/Makefile.mingw b/contrib/unifdef/win32/Makefile.mingw
new file mode 100644
index 000000000000..63e0411d737d
--- /dev/null
+++ b/contrib/unifdef/win32/Makefile.mingw
@@ -0,0 +1,14 @@
+# To build, run:
+# mingw32-make -f win32/Makefile.mingw
+
+all: unifdef.exe
+
+unifdef.exe: unifdef.c win32/win32.c FreeBSD/getopt.c FreeBSD/err.c
+	cd win32 && \
+	cp ../unifdef.c ../version.h . && \
+	$(CC) $(CFLAGS) $(LDFLAGS) -I. -o ../unifdef.exe unifdef.c \
+		win32.c ../FreeBSD/getopt.c ../FreeBSD/err.c && \
+	rm -f unifdef.c version.h
+
+test: unifdef.exe
+	scripts/runtests.sh tests
diff --git a/contrib/unifdef/win32/unifdef.h b/contrib/unifdef/win32/unifdef.h
new file mode 100644
index 000000000000..2fe301bd026e
--- /dev/null
+++ b/contrib/unifdef/win32/unifdef.h
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2012 - 2015 Tony Finch <dot@dotat.at>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* Stop being stupid about POSIX functions */
+#define _CRT_SECURE_NO_WARNINGS
+#define _SCL_SECURE_NO_WARNINGS
+#define _CRT_NONSTDC_NO_WARNINGS
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* Windows POSIX-flavoured headers */
+
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <io.h>
+
+#define stat     _stat
+
+/* fake stdbool.h */
+#define true 1
+#define false 0
+#define bool int
+
+/* used by err.c and getopt.c */
+#define _getprogname() "unifdef"
+
+/*
+ * The snprintf() workaround is unnecessary in Visual Studio 2015 or later
+ * but dogma dictates that #if directives are not allowed inside unifdef.
+ */
+#define snprintf c99_snprintf
+
+/* win32.c */
+int replace(const char *oldname, const char *newname);
+FILE *mktempmode(char *tmp, int mode);
+FILE *fbinmode(FILE *fp);
+int c99_snprintf(char *buf, size_t buflen, const char *format, ...);
+
+/* err.c */
+void err(int, const char *, ...);
+void verr(int, const char *, va_list);
+void errc(int, int, const char *, ...);
+void verrc(int, int, const char *, va_list);
+void errx(int, const char *, ...);
+void verrx(int, const char *, va_list);
+void warn(const char *, ...);
+void vwarn(const char *, va_list);
+void warnc(int, const char *, ...);
+void vwarnc(int, const char *, va_list);
+void warnx(const char *, ...);
+void vwarnx(const char *, va_list);
+
+/* getopt.c */
+int getopt(int nargc, char *nargv[], const char *ostr);
+extern int opterr, optind, optopt, optreset;
+extern char *optarg;
diff --git a/contrib/unifdef/win32/unifdef.sln b/contrib/unifdef/win32/unifdef.sln
new file mode 100644
index 000000000000..ae2053f00387
--- /dev/null
+++ b/contrib/unifdef/win32/unifdef.sln
@@ -0,0 +1,20 @@
+
+Microsoft Visual Studio Solution File, Format Version 11.00
+# Visual Studio 2010
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "unifdef", "unifdef.vcxproj", "{52450E07-855E-4522-BD4C-7B1E84D8D592}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Win32 = Debug|Win32
+		Release|Win32 = Release|Win32
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{52450E07-855E-4522-BD4C-7B1E84D8D592}.Debug|Win32.ActiveCfg = Debug|Win32
+		{52450E07-855E-4522-BD4C-7B1E84D8D592}.Debug|Win32.Build.0 = Debug|Win32
+		{52450E07-855E-4522-BD4C-7B1E84D8D592}.Release|Win32.ActiveCfg = Release|Win32
+		{52450E07-855E-4522-BD4C-7B1E84D8D592}.Release|Win32.Build.0 = Release|Win32
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal
diff --git a/contrib/unifdef/win32/unifdef.vcxproj b/contrib/unifdef/win32/unifdef.vcxproj
new file mode 100644
index 000000000000..7f79e4dd7a1d
--- /dev/null
+++ b/contrib/unifdef/win32/unifdef.vcxproj
@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|Win32">
+      <Configuration>Debug</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|Win32">
+      <Configuration>Release</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <ProjectGuid>{52450E07-855E-4522-BD4C-7B1E84D8D592}</ProjectGuid>
+    <Keyword>Win32Proj</Keyword>
+    <RootNamespace>unifdef</RootNamespace>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <CharacterSet>MultiByte</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+  <ImportGroup Label="ExtensionSettings">
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <LinkIncremental>false</LinkIncremental>
+  </PropertyGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <ClCompile>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <Optimization>Disabled</Optimization>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;_CRT_SECURE_NO_WARNINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <AdditionalIncludeDirectories>.\</AdditionalIncludeDirectories>
+      <PrecompiledHeaderFile>unifdef.h</PrecompiledHeaderFile>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <Optimization>MaxSpeed</Optimization>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;_CRT_SECURE_NO_WARNINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <AdditionalIncludeDirectories>.\</AdditionalIncludeDirectories>
+      <PrecompiledHeaderFile>unifdef.h</PrecompiledHeaderFile>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup>
+    <ClInclude Include="..\version.h" />
+    <ClInclude Include="..\win32\unifdef.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="..\unifdef.c" />
+    <ClCompile Include="..\FreeBSD\err.c" />
+    <ClCompile Include="..\FreeBSD\getopt.c" />
+    <ClCompile Include="win32.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">Create</PrecompiledHeader>
+    </ClCompile>
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <ImportGroup Label="ExtensionTargets">
+  </ImportGroup>
+</Project>
diff --git a/contrib/unifdef/win32/win32.c b/contrib/unifdef/win32/win32.c
new file mode 100644
index 000000000000..931b8194500b
--- /dev/null
+++ b/contrib/unifdef/win32/win32.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2012 - 2014 Tony Finch <dot@dotat.at>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "unifdef.h"
+
+/*
+ * The Windows implementation of rename() fails if the new filename
+ * already exists. Atomic replacement is not really needed, so just
+ * remove anything that might be in the way before renaming.
+ */
+int
+replace(const char *oldname, const char *newname)
+{
+	if (remove(newname) < 0 && errno != ENOENT)
+		warn("can't remove \"%s\"", newname);
+	return (rename(oldname, newname));
+}
+
+FILE *
+mktempmode(char *tmp, int mode)
+{
+	mode = mode;
+	return (fopen(_mktemp(tmp), "wb"));
+}
+
+FILE *
+fbinmode(FILE *fp)
+{
+	_setmode(_fileno(fp), _O_BINARY);
+	return (fp);
+}
+
+/*
+ * This is more long-winded than seems necessary because MinGW
+ * doesn't have a proper implementation of _vsnprintf_s().
+ *
+ * This link has some useful info about snprintf() on Windows:
+ * http://stackoverflow.com/questions/2915672/snprintf-and-visual-studio-2010
+ */
+int c99_snprintf(char *buf, size_t buflen, const char *format, ...)
+{
+	va_list ap;
+	int outlen, cpylen, tmplen;
+	char *tmp;
+
+	va_start(ap, format);
+	outlen = _vscprintf(format, ap);
+	va_end(ap);
+	if (buflen == 0 || outlen < 0)
+		return outlen;
+	if (buflen > outlen)
+		cpylen = outlen;
+	else
+		cpylen = buflen - 1;
+	/* Paranoia about off-by-one errors in _snprintf() */
+	tmplen = outlen + 2;
+
+	tmp = (char *)malloc(tmplen);
+	if (tmp == NULL)
+		err(2, "malloc");
+	va_start(ap, format);
+	_vsnprintf(tmp, tmplen, format, ap);
+	va_end(ap);
+	memcpy(buf, tmp, cpylen);
+	buf[cpylen] = '\0';
+	free(tmp);
+
+	return outlen;
+}