diff --git a/contrib/mandoc/TODO b/contrib/mandoc/TODO index fe2059c9e5d5..4135a3eca6c8 100644 --- a/contrib/mandoc/TODO +++ b/contrib/mandoc/TODO @@ -1,721 +1,719 @@ ************************************************************************ * Official mandoc TODO. * $Id: TODO,v 1.319 2021/09/21 17:58:13 schwarze Exp $ ************************************************************************ Many issues are annotated for difficulty as follows: - loc = locality of the issue * single file issue, affects file only, or very few ** single module issue, affects several files of one module *** cross-module issue, significantly impacts multiple modules and may require substantial changes to internal interfaces - exist = difficulty of the existing code in this area * affected code is straightforward and easy to read and change ** affected code is somewhat complex, but once you understand the design, not particularly difficult to understand *** affected code uses a special, exceptionally tricky design - algo = difficulty of the new algorithm to be written * the required logic and code is straightforward ** the required logic is somewhat complex and needs a careful design *** the required logic is exceptionally tricky, maybe an approach to solve that is not even known yet - size = the amount of code to be written or changed * a small number of lines (at most 100, usually much less) ** a considerable amount of code (several dozen to a few hundred) *** a large amount of code (many hundreds, maybe thousands) - imp = importance of the issue * mostly for completeness ** would be nice to have *** issue causes considerable inconvenience Obviously, as the issues have not been solved yet, these annotations are mere guesses, and some may be wrong. ************************************************************************ * assertion failures ************************************************************************ - .if n .ce in the middle of .TS data afl case f1/id:000103,sig:06,src:009024+009105,op:splice,rep:2 (jes@) While roff_parseln() prevents .ce and similar requests in the middle of a tbl, the guard is no longer effective when the .ce is wrapped in a roff block, for example a conditional. The resulting assertion has never been seen in any real-world manual page. This is too dangerous to fix before release because it requires reorganizing the very delicate internals of roff_parseln(), which risks causing more severe bugs. loc * exist *** algo *** size * imp * ************************************************************************ * bugs: invalid output ************************************************************************ - wrong number of layout columns in tbl(7) code generated by -T man https://savannah.gnu.org/bugs/?57720 The reason likely is that tbl(7) does not support the -Bl -column feature of not explicitly specifying the last table column. loc ** exist * algo ** size * imp *** - eqn(7) delimiters cause conditional lines to misbehave nabijaczleweli 8 Sep 2021 15:24:48 +0200 loc * exist *** algo *** size * imp * - roff.c, roff_expand() should not remove blanks before comments to Oliver Corff, Sep 7, 2021 loc * exist * algo * size * imp * but watch out for regressions in the high-level parsers maybe it should not even remove comments? - consider T{\" ************************************************************************ * missing features ************************************************************************ --- missing roff features ---------------------------------------------- - .ad (adjust margins) .ad l -- adjust left margin only (flush left) .ad r -- adjust right margin only (flush right) .ad c -- center text on line .ad b -- adjust both margins (alias: .ad n) .na -- temporarily disable adjustment without changing the mode .ad -- re-enable adjustment without changing the mode Adjustment mode is ignored while in no-fill mode (.nf). loc *** exist *** algo ** size ** imp ** (parser reorg would help) - .fc (field control) found by naddy@ in xloadimage(1) loc ** exist *** algo * size * imp * - .ns (no-space mode) occurs in xine-config(1) when implementing this, also let .TH set it reported by brad@ Sat, 15 Jan 2011 15:45:23 -0500 loc *** exist *** algo *** size ** imp * - \w'' improve width measurements would not be very useful without an expression parser, see below needed for Tcl_NewStringObj(3) via wiz@ Wed, 5 Mar 2014 22:27:43 +0100 loc ** exist *** algo *** size * imp *** - .als only works for macros in mandoc, not for user-defined strings. Also, the "val" field in struct roffkv would have to be replaced with a pointer to a reference-counted wrapper, and an alias would have to point to the same wrapper as the original. .als to undefined does nothing; the alias is not created. .rm'ing the original leaves the alias to point to the old value. .de .als .de changes both, but .de .als .rm .de only changes the new value, not the alias. Found in groffer(1) version 1.19 Jan Stary 20 Apr 2019 20:16:54 +0200 loc * exist ** algo ** size ** imp * - roff string condition comparisons fail when vars contain quotes: .ds s ' .if '\*s'' \&... hard to fix because of the basic architecture (string replacement happens before roff(7) syntax parsing) Found in groffer(1) version 1.19 Jan Stary 20 Apr 2019 20:16:54 +0200 loc * exist *** algo *** size ** imp * - mandoc replaces all ASCII control characters except tab and line feed with '?' during input. It would be better to replace them with Unicode escapes in preconv_encode() or somewhere in the vicinity, such that the already existing better replacement strings show up in the output. Emulating groff is not desirable: groff replaces 0x00, 0x0b, and 0x0d to 0x1f with the empty string (bad because that's easy to overlook for the document author), 0x01 with '.' (very confusing), and passes through 0x02 to 0x08, 0x0c, and 0x7f raw (bad because that is insecure output). Remember that 0x07 may need special handling because it is sometimes used for certain delimiters, so it may need handling *after* roff.c rather than before. reminded by John Gardner 16 Jun 2020 14:26:28 +1000 Actually, more ASCII control characters than just 0x07 may need later handling because they can for example be used in macro names. So they may need handling after roff(7) processing. pointed out by John Gardner 23 Jun 2020 18:28:08 +1000 more info from John Gardner 29 Jun 2020 19:54:04 +1000 loc ** exist ** algo ** size ** imp * - many missing features used in old groff_char(7), some can possibly be supported kamil at netbsd 12 Nov 2020 17:27:09 +0100 + reply - \s with arbitrary arg delimiters as already supported for other escapes found following jmc@'s mail 28 Apr 2021 18:31:41 +0100 loc * exist * algo * size * imp * --- missing mdoc features ---------------------------------------------- - .Sh and .Ss should be parsed and partially callable, see groff_mdoc(7) reed at reedmedia dot net Sat, 21 Dec 2019 17:13:07 -0600 loc ** exist ** algo ** size ** imp * - .Bl -column .Xo support is missing ultimate goal: restore .Xr and .Dv to lib/libc/compat-43/sigvec.3 lib/libc/gen/signal.3 lib/libc/sys/sigaction.2 loc * exist *** algo *** size * imp ** - edge case: decide how to deal with blk_full bad nesting, e.g. .Sh .Nm .Bk .Nm .Ek .Sh found by jmc@ in ssh-keygen(1) from jmc@ Wed, 14 Jul 2010 18:10:32 +0100 loc * exist *** algo *** size ** imp ** - .Bd -filled should not be the same as .Bd -ragged, but align both the left and right margin. In groff, it is implemented in terms of .ad b, which we don't have either. Found in cksum(1). loc *** exist *** algo ** size ** imp ** (parser reorg would help) - implement blank `Bl -column', such as .Bl -column .It foo Ta bar .El loc * exist *** algo *** size * imp * - explicitly disallow nested `Bl -column', which would clobber internal flags defined for struct mdoc_macro loc * exist * algo * size * imp ** - In .Bl -column .It, the end of the line probably has to be regarded as an implicit .Ta, if there could be one, see the following mildly ugly code from login.conf(5): .Bl -column minpasswordlen program xetcxmotd .It path Ta path Ta value of Dv _PATH_DEFPATH .br Default search path. reported by Michal Mazurek via jmc@ Thu, 7 Apr 2011 16:00:53 +0059 loc * exist *** algo ** size * imp ** - inside `.Bl -column' phrases, punctuation is handled like normal text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -." - inside `.Bl -column' phrases, TERMP_IGNDELIM handling by `Pf' is not safe, e.g. `.Bl -column .It Pf a b .' gives "ab." but should give "ab ." - prohibit `Nm' from having non-text HEAD children (e.g., NetBSD mDNSShared/dns-sd.1) (mdoc_html.c and mdoc_term.c `Nm' handlers can be slightly simplified) - support translated section names e.g. x11/scrotwm scrotwm_es.1:21:2: error: NAME section must be first that one uses NOMBRE because it is spanish... deraadt tends to think that section-dependent macro behaviour is a bad idea in the first place, so this may be irrelevant loc ** exist ** algo ** size * imp ** - When there is free text in the SYNOPSIS and that free text contains the .Nm macro, groff somehow understands to treat the .Nm as an in-line macro, while mandoc treats it as a block macro and breaks the line. No idea how the logic for distinguishing in-line and block instances should be, needs investigation. uqs@ Thu, 2 Jun 2011 11:03:51 +0200 uqs@ Thu, 2 Jun 2011 11:33:35 +0200 loc * exist ** algo *** size * imp ** --- missing man features ----------------------------------------------- - MANWIDTH Markus Waldeck 9 Jun 2015 05:49:56 +0200 Laura Morales 26 Apr 2018 08:15:55 +0200 Kamil Rytarowski 13 Nov 2020 00:19:36 +0100 patch from Kamil 13 Nov 2020 22:37:07 +0100 loc * exist * algo * size * imp * - groff_www(7) .MTO and .URL These macros were used by the GNU grep(1) man page. The groff_www(7) manual page itself uses them, too. We should probably *not* add them to mandoc. Just mentioning this here to keep track of the abuse. Laura Morales 20 Apr 2018 07:33:02 +0200 loc ** exist * algo * size ** imp * --- missing tbl features ----------------------------------------------- - vertical centering in cells vertically spanned with ^ pali dot rohar at gmail dot com 16 Jul 2018 13:03:35 +0200 loc * exist *** algo *** size ** imp * - support mdoc(7) and man(7) macros inside tbl(7) code; probably requires the parser reorg and letting tbl(7) use roff_node such that macro sets can mix; informed by bapt@ that FreeBSD needs this: 3 Jan 2015 23:32:23 +0100 loc *** exist ** algo *** size ** imp *** - look at the POSIX manuals in the books/man-pages-posix port, they use some unsupported tbl(7) features, mostly macros in tbl(7). loc * exist ** algo ** size ** imp *** - look what Joerg Schilling manual pages use Thu, 19 Mar 2015 18:31:48 +0100 --- missing eqn features ----------------------------------------------- - In a matrix, break the output line after each matrix line. Found in the discussion at CDBUG 2015. Suggested by Avi Weinstock. This may not be the ideal solution after all: eqn(7) matrices are lists of columns, so Avi's proposal would show each *column* on its own *line*, which is likely to cause confusion. A better solution, but much harder to implement, would be to actually show the coordinates of column vectors on different terminal output lines, using the clumnated output facilities developed for .Bl -tag, .Bl -column, and also used for tbl(7). loc * exist * algo ** size ** imp ** - The "size" keyword is parsed, but ignored by the formatter. loc * exist * algo * size * imp * - The spacing characters `~', `^', and tab are currently ignored, see User's Guide (Second Edition) page 2 section 4. loc * exist * algo ** size * imp ** - Mark and lineup are parsed and ignored, see User's Guide (Second Edition) page 5 section 15. loc ** exist ** algo ** size ** imp ** - GNU eqn converts some operators to special characters, for example, input HYPHEN-MINUS becomes output \(mi, unless it is part of a quoted word. mandoc(1) only does this when the operator is surrounded by blanks, not when it is part of an unquoted word. Also, check whether there are more such cases (e.g., +?). reported by bentley@ 20 Jun 2017 02:04:29 -0600 loc * exist ** algo ** size * imp * - Primes, opprime, and ' bentley@ Thu, 13 Jul 2017 23:14:20 -0600 --- missing misc features ---------------------------------------------- - conisder whether man(1) fallback code in main.c/fs_*() can find files like man3c/fopen.3c (illumos, Solaris) and man3p/fopen.3p (POSIX) discussed with Robert Mustacchi 21 Sep 2021 10:39:40 -0700 loc * exist * algo ** size * imp ** - let makewhatis(8) follow symbolic links to dirs below READ_ALLOWED_PATH this may be feasible using fts_set(FTS_FOLLOW) mail to sternenseemann 19 Aug 2021 19:11:50 +0200 loc * exist ** algo ** size * imp ** - -T man does not handle eqn(7) and tbl(7) Stephen Gregoratto 16 Feb 2020 01:28:07 +1100 also https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=901636 loc ** exist ** algo ** size *** imp ** - man -ks 1,8 route; kn@ Jul 13, 2018 orally - italic correction (\/) in PostScript mode Werner LEMBERG on groff at gnu dot org Sun, 10 Nov 2013 12:47:46 loc ** exist ** algo * size * imp * - change the default PAGER to more -Es and use the pager even for apropos title line output; req by bapt@ loc * exist * algo * size * imp *** - clean up escape sequence handling, creating three classes: (1) fully implemented, or parsed and ignored without loss of content (2) unimplemented, potentially causing loss of content or serious mangling of formatting (e.g. \n) -> ERROR see textproc/mgdiff(1) for nice examples (3) undefined, just output the character -> perhaps WARNING loc *** exist ** algo ** size ** imp *** (parser reorg helps) - kettenis wants base roff, ms, and me Fri, 1 Jan 2010 22:13:15 +0100 (CET) loc ** exist ** algo ** size *** imp * --- compatibility checks ----------------------------------------------- - is .Bk implemented correctly in modern groff? sobrado@ Tue, 19 Apr 2011 22:12:55 +0200 - compare output to Heirloom roff, Solaris roff, and http://repo.or.cz/w/neatroff.git http://litcave.rudi.ir/ - look at AT&T DWB http://www2.research.att.com/sw/download Carsten Kunze has patches Mon, 4 Aug 2014 17:01:28 +0200 ported version: https://github.com/n-t-roff/DWB3.3 Carsten Kunze Wed, 22 Apr 2015 11:21:43 +0200 - look at pages generated from reStructeredText, e.g. devel/mercurial hg(1) These are a weird mixture of man(7) and custom autogenerated low-level roff stuff. Figure out to what extent we can cope. For details, see http://docutils.sourceforge.net/rst.html noted by stsp@ Sat, 24 Apr 2010 09:17:55 +0200 reminded by nicm@ Mon, 3 May 2010 09:52:41 +0100 - look at pages generated from ronn(1) github.com/rtomayko/ronn (based on markdown) - look at pages generated from Texinfo source by yat2m, e.g. security/gnupg First impression is not that bad. - look at pages generated by pandoc; see https://github.com/jgm/pandoc/blob/master/src/Text/Pandoc/Writers/Man.hs porting planned by kili@ Thu, 19 Jun 2014 19:46:28 +0200 - check compatibility with Plan9: http://swtch.com/usr/local/plan9/tmac/tmac.an http://swtch.com/plan9port/man/man7/man.html "Anthony J. Bentley" 28 Dec 2010 21:58:40 -0700 - check compatibility with COHERENT troff: http://www.nesssoftware.com/home/mwc/source.php - check compatibility with the man(7) formatter https://raw.githubusercontent.com/rofl0r/hardcore-utils/master/man.c - check compatibility with http://ikiwiki.info/plugins/contrib/mandoc/ https://github.com/schmonz/ikiwiki/compare/mandoc Amitai Schlair Mon, 19 May 2014 14:05:53 -0400 - check compatibility with https://git.sr.ht/~sircmpwn/scdoc - check features of the Slackware man.conf(5) format Carsten Kunze Wed, 11 Mar 2015 17:57:24 +0100 - look at http://www.snake.net/software/troffcvt/ (troff to HTML) mentioned by Oliver Corff 22 Jan 2021 01:36:49 +0100 ************************************************************************ * formatting issues: ugly output ************************************************************************ - revisit empty in-line macros look at the difference between "Em x Em ." and "Sq x Em ." Carsten Kunze Fri, 12 Dec 2014 00:15:41 +0100 loc *** exist *** algo *** size * imp ** - a column list with blank `Ta' cells triggers a spurious start-with-whitespace printing of a newline - In .Bl -column, .It a"bc" shows the quotes in groff, but not in mandoc loc * exist *** algo ** size * imp ** - In .Bl -column, .It Em AuthenticationKey Length ought to render "Key Length" with emphasis, too, see OpenBSD iked.conf(5). reported again Nicolas Joly via wiz@ Wed, 12 Oct 2011 00:20:00 +0200 loc * exist *** algo *** size ** imp *** - empty phrases in .Bl column produce too few blanks try e.g. .Bl -column It Ta Ta reported by millert Fri, 02 Apr 2010 16:13:46 -0400 loc * exist *** algo *** size * imp ** - .%T can have trailing punctuation. Currently, it puts the trailing punctuation into a trailing MDOC_TEXT element inside its own scope. That element should rather be outside its scope, such that the punctuation does not get underlines. This is not trivial to implement because .%T then needs some features of in_line_eoln() - slurp all arguments into one single text element - and one feature of in_line() - put trailing punctuation out of scope. Found in mount_nfs(8) and exports(5), search for "Appendix". loc ** exist ** algo *** size * imp ** - Trailing punctuation after .%T triggers EOS spacing, at least outside .Rs (eek!). Simply setting ARGSFL_DELIM for .%T is not the right solution, it sends mandoc into an endless loop. reported by Nicolas Joly Sat, 17 Nov 2012 11:49:54 +0100 loc * exist ** algo ** size * imp ** - global variables in the SYNOPSIS of section 3 pages .Vt vs .Vt/.Va vs .Ft/.Va vs .Ft/.Fa ... from kristaps@ Tue, 08 Jun 2010 11:13:32 +0200 - implicit whitespace around inline equations example code: where '$times$' denotes matrix multiplication must not have an HTML line break, nor a blank, before partial solution: html.c {"math", HTML_NLINSIDE | HTML_INDENT}, bentley@ Thu, 13 Jul 2017 19:00:59 -0600 - in enclosures, mandoc sometimes fancies a bogus end of sentence reminded by jmc@ Thu, 23 Sep 2010 18:13:39 +0059 loc * exist ** algo *** size * imp *** - a line starting with "\fB something" counts as starting with whitespace and triggers a line break; found in audio/normalize-mp3(1) This will become easier once escape sequences are represented by syntax tree nodes. loc ** exist * algo ** size * imp ** - formatting /usr/local/man/man1/latex2man.1 with groff and mandoc reveals lots of bugs both in groff and mandoc... reported by bentley@ Wed, 22 May 2013 23:49:30 -0600 --- PostScript and PDF issues ------------------------------------------ - PDF output doesn't use a monospaced font for .Bd -literal Example: "mandoc -Tpdf afterboot.8 > output.pdf && pdfviewer output.pdf". Search the text "Routing tables". Also check what PostScript mode does when fixing this. reported by juanfra@ Wed, 04 Jun 2014 21:44:58 +0200 instructions from juanfra@ Wed, 11 Jun 2014 02:21:01 +0200 add a new <> block to the PDF files with /BaseFont /Courier and change the /Name from /F0 to the new font (/F5 (?)). re-reported by tb@ Mon, 16 Mar 2015 16:47:21 +0100 loc ** exist ** algo ** size * imp ** --- HTML issues -------------------------------------------------------- - make the HTML scaffolding customozable with -O skip=... mail to Oliver Corff 3 Jun 2021 17:28:02 +0200 more feedback from Oliver 3 Jun 2021 18:27:56 +0200 more feedback from Oliver 3 Jun 2021 23:37:18 +0200 - .Bd -unfilled should not use monospaced font anton@ 4 Mar 2021 08:19:35 +0100 loc ** exist * algo * size * imp ** - HTML formatting of .nf should avoid
and not close and re-open 
 on .P
   my mail to ports@ 27 Jun 2021 16:09:20 +0200
   loc **  exist **  algo *  size *  imp **
 
 - get rid of the last handful of style= attributes such that
   Content-Security-Policy: can be enabled without unsafe-inline
   suggested by bentley@  Nov 10, 2019 at 06:02:49AM -0700
   loc *  exist *  algo *  size *  imp **
 
 - .Bf at the beginning of a paragraph inserts a bogus 1ex horizontal
   space, see for example random(3).  Introduced in
   http://mdocml.bsd.lv/cgi-bin/cvsweb/mdoc_html.c.diff?r1=1.91&r2=1.92
   reported by deraadt@ Mon, 28 Sep 2015 20:14:13 -0600 (MDT)
   loc **  exist **  algo **  size *  imp *
 
 - jsg on icb, Nov 3, 2014:
   try to guess Xr in man(7) for hyperlinking
   and render them with 
   https://github.com/Debian/debiman/issues/15
   loc *  exist *  algo **  size **  imp **
 
 - space characters can end up in href= attributes, for example coming
   from the first .Xr argument (where they make no sense, but still);
   does this affect other characters, other source macros...?
   Jackson Pauls  29 Aug 2017 16:56:27 +0100
 
 - The tables used to render the three-part page headers actually force
   the width of the  to the max-width given for .
   Not yet sure how to fix that...
   Observed by an Anonymous Coward on undeadly.org:
   http://undeadly.org/cgi?action=article&sid=20140925064244&pid=1
   loc *  exist *  algo **  size *  imp ***
 
 - generate  tags in HTML
   idea from florian@  Tue, 7 Apr 2015 00:26:28 +0000
   may be possible to implement with .Lk img://something.png alt_text
 
 - check https://github.com/trentm/mdocml
 
 ************************************************************************
 * formatting issues: gratuitous differences
 ************************************************************************
 
 - .Fn reopens a new scope after punctuation in mandoc,
   but closes its scope for good in groff.
   Do we want to change mandoc or groff?
   Steffen Nurpmeso  Sat, 08 Nov 2014 13:34:59 +0100
   loc *  exist **  algo **  size *  imp **
 
 - In .Bl -enum -width 0n, groff continues one the same line after
   the number, mandoc breaks the line.
   mail to kristaps@  Mon, 20 Jul 2009 02:21:39 +0200
   loc *  exist **  algo **  size *  imp **
 
 - .Pp between two .It in .Bl -column should produce one,
   not two blank lines, see e.g. login.conf(5).
   reported by jmc@  Sun, 17 Apr 2011 14:04:58 +0059
   reported again by sthen@  Wed, 18 Jan 2012 02:09:39 +0000 (UTC)
   loc *  exist ***  algo **  size *  imp **
 
 - If the *first* line after .It is .Pp, break the line right after
   the tag, do not pad with space characters before breaking.
   See the description of the a, c, and i commands in sed(1).
   loc *  exist **  algo **  size *  imp **
 
 - If the first line after .It is .D1, do not assert a blank line
   in between, see for example tmux(1).
   reported by nicm@  13 Jan 2011 00:18:57 +0000
   loc *  exist **  algo **  size *  imp **
 
 - Trailing punctuation after .It should trigger EOS spacing.
   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
   Probably, this should be fixed somewhere in termp_it_pre(), not sure.
   loc *  exist **  algo **  size *  imp **
 
 - When the -width string contains macros, the macros must be rendered
   before measuring the width, for example
     .Bl -tag -width ".Dv message"
   in magic(5), located in src/usr.bin/file, is the same
   as -width 7n, not -width 11n.
   The same applies to .Bl -column column widths;
   reported again by Nicolas Joly Thu, 1 Mar 2012 13:41:26 +0100 via wiz@ 5 Mar
   reported again by Franco Fichtner Fri, 27 Sep 2013 21:02:28 +0200
   reported again by Bruce Evans Fri, 17 Feb 2017 21:22:44 +0100 via bapt@
   loc ***  exist ***  algo ***  size **  imp ***
-  An easy partial fix would be to just skip the first word if it starts
-  with a dot, including any following white space, when measuring.
-  loc *  exist *  algo *  size *  imp ***
+  An easy partial fix has been implemented as skip_leading_dot_word().
 
 - The \& zero-width character counts as output.
   That is, when it is alone on a line between two .Pp,
   we want three blank lines, not two as in mandoc.
   loc **  exist **  algo **  size *  imp **
 
 - Sequences of multiple man(7) paragraphs (.PP, .IP) interspersed
   with .ps and .nf/.fi produce execessive blank lines, see libJudy
   and graphics/dcmtk.  The parser reorg may help with this.
 
 - trailing whitespace must be ignored even when followed by a font escape,
   see for example
     makes
     \fBdig \fR
     operate in batch mode
   in dig(1).
   loc **  exist **  algo **  size *  imp **
 
 ************************************************************************
 * warning issues
 ************************************************************************
 
 - shorten/simplify error messages for usage errors
   To: deraadt@ 25 Oct 2020 23:37:01 +0100
   loc **  exist *  algo *  size **  imp ***
 
 - warn about duplicate .Sh/.Ss heads
   gre(4): Rename duplicate sections 20 Apr 2018 15:27:33 +0200
   loc *  exist *  algo *  size *  imp **
 
 - style message about macros inside .Bd -literal and .Dl, in particular
   font changing macros like .Cm, .Ar, .Fa (from the mdoclint TODO)
 
 - style message about mismatches between the section number in the
   file name (if it is known) and the section number in .Dt
   (from the mdoclint TODO)
 
 - style message about NULL without .Dv (from the mdoclint TODO)
 
 - style message about error constants without .Er (from the mdoclint TODO)
 
 - warn when .Sh or .Ss contain other macros
   Steffen Nurpmeso, savannah.gnu.org/bugs/index.php?45034
   loc *  exist *  algo *  size *  imp **
 
 - style message about violations of the convention
   .An name Aq Mt localpart@domain in AUTHORS (from the mdoclint TODO)
 
 - warn about attempts to call non-callable macros
   Steffen Nurpmeso  Tue, 11 Nov 2014 22:55:16 +0100
   Note that formatting is inconsistent in groff.
   .Fn Po prints "Po()", .Ar Sh prints "file ..." and no "Sh".
   Relatively hard because the relevant code is scattered
   all over mdoc_macro.c and all subtly different.
   loc **  exist **  algo **  size **  imp **
 
 - warn about punctuation - e.g. ',' and ';' - at the beginning
   of a text line, if it is likely intended to follow the preceding
   output without intervening whitespace, in particular after a
   macro line (from the mdoclint TODO)
 
 - report double .TH in man(7) as an ERROR and let the first win
   kristaps@  28 Mar 2021 13:30:41 +0200
   loc *  exist *  algo *  size *  imp *
 
 - makewhatis -p complains about language subdirectories:
   /usr/local/man//ru: Unknown directory part
 
 
 ************************************************************************
 * documentation issues
 ************************************************************************
 
 - mark macros as: page structure domain, manual domain, general text domain
   is this useful?
 
 - mention /usr/share/misc/mdoc.template in mdoc(7)?
 
 - Is all the content from http://www.std.com/obi/BSD/doc/usd/28.tbl/tbl
   covered in tbl(7)?
 
 ************************************************************************
 * performance issues
 ************************************************************************
 
 - the PDF file is HUGE: this can be reduced by using relative offsets
 
 ************************************************************************
 * structural issues
 ************************************************************************
 
 - POSIX says in the documentation of sysconf(3) that PATH_MAX
   is allowed to be so large that it is a bad idea to use it
   for sizing static buffers.  So use dynamic buffers throughout.
   See the file test-PATH_MAX.c for details.
   Found by Aaron M. Ucko in the GNU Hurd via Bdale Garbee,
   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829624
 
 - Is it possible to further simplify ENDBODY_SPACE?
 
 - Find better ways to prevent endless loops
   in roff(7) macro and string expansion.
 
 - make buffers for parsing functions const
   christos@ via wiz@  Fri, 18 Dec 2015 17:10:01 +0100
 
 - struct mparse refactoring
   Steffen Nurpmeso  Thu, 04 Sep 2014 12:50:00 +0200
 
 ************************************************************************
 * CGI issues
 ************************************************************************
 
  - Inspect httpd(8) logs on man.openbsd.org and consider
    whether logging can be improved, where bad syntax comes from,
    and what needs to be done to get rid of COMPAT_OLDURI.
  - Enable HTTP compression by detecting gzip encoding and filtering
    output through libz.
  - Privilege separation (see OpenSSH).
  - Enable caching support via HTTP 304 and If-Modified-Since.
 
 ************************************************************************
 * to improve in the groff_mdoc(7) macros
 ************************************************************************
 
 - delete OS release verification from .Dx, .Fx, .Nx, .Ox etc.
   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=629161
   also Branden Robinson 18 Dec 2019 00:59:52 +1100
 
 - Can the distinction between .Vt and .Va be made stricter,
   recommending .Vt extern char * Ns Va optarg ; ?
   What about the block macro properties of .Vt in the SYNOPSIS?
   zeurkous 25 Dec 2019 08:48:36 +0100
 
 - .Cd # arch1, arch2 in section 4 pages:
   find better way to indicate multiple architectures, maybe:
   allow .Dt vgafb 4 "macppc sparc64"
   already shown as "Device Drivers Manual (macppc sparc64)"
   for apropos, make that "vgafb(4) - macppc # sparc64" instead of "- all"
   groff can be made to show multiple arches, too, but it is
   tedious to do the string parsing in roff code...
   jmc@ 23 Apr 2018 07:24:52 +0100 [man for vgafb(4)...]
   loc **  exist **  algo *  size *  imp ***
 
 - use uname(1) to set doc-default-operating-system at install time
   tobimensch  Mon, 1 Dec 2014 00:25:07 +0100
 
 - apostrophe (39), circumflex (94), grave (96), tilde (126)
   in manuals: \(aq, \(ha, \`, \(ti
   Re: [Groff] ASCII Minus Sign in man Pages.
   bentley@ 26 Apr 2017 10:02:06 -0600
   Do we need to fix existing manuals?
   Do we need to fix the definition of the mdoc(7) language?
diff --git a/contrib/mandoc/mdoc_validate.c b/contrib/mandoc/mdoc_validate.c
index e1cd3ae1edcb..5c40842b1ae1 100644
--- a/contrib/mandoc/mdoc_validate.c
+++ b/contrib/mandoc/mdoc_validate.c
@@ -1,3062 +1,3106 @@
 /* $Id: mdoc_validate.c,v 1.389 2021/07/18 11:41:23 schwarze Exp $ */
 /*
  * Copyright (c) 2010-2020 Ingo Schwarze 
  * Copyright (c) 2008-2012 Kristaps Dzonsons 
  * Copyright (c) 2010 Joerg Sonnenberger 
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *
  * Validation module for mdoc(7) syntax trees used by mandoc(1).
  */
 #include "config.h"
 
 #include 
 #ifndef OSNAME
 #include 
 #endif
 
 #include 
 #include 
 #include 
 #include 
 #include 
 #include 
 #include 
 
 #include "mandoc_aux.h"
 #include "mandoc.h"
 #include "mandoc_xr.h"
 #include "roff.h"
 #include "mdoc.h"
 #include "libmandoc.h"
 #include "roff_int.h"
 #include "libmdoc.h"
 #include "tag.h"
 
 /* FIXME: .Bl -diag can't have non-text children in HEAD. */
 
 #define	POST_ARGS struct roff_man *mdoc
 
 enum	check_ineq {
 	CHECK_LT,
 	CHECK_GT,
 	CHECK_EQ
 };
 
 typedef	void	(*v_post)(POST_ARGS);
 
 static	int	 build_list(struct roff_man *, int);
 static	void	 check_argv(struct roff_man *,
 			struct roff_node *, struct mdoc_argv *);
 static	void	 check_args(struct roff_man *, struct roff_node *);
 static	void	 check_text(struct roff_man *, int, int, char *);
 static	void	 check_text_em(struct roff_man *, int, int, char *);
 static	void	 check_toptext(struct roff_man *, int, int, const char *);
 static	int	 child_an(const struct roff_node *);
 static	size_t		macro2len(enum roff_tok);
 static	void	 rewrite_macro2len(struct roff_man *, char **);
 static	int	 similar(const char *, const char *);
 
 static	void	 post_abort(POST_ARGS) __attribute__((__noreturn__));
 static	void	 post_an(POST_ARGS);
 static	void	 post_an_norm(POST_ARGS);
 static	void	 post_at(POST_ARGS);
 static	void	 post_bd(POST_ARGS);
 static	void	 post_bf(POST_ARGS);
 static	void	 post_bk(POST_ARGS);
 static	void	 post_bl(POST_ARGS);
 static	void	 post_bl_block(POST_ARGS);
 static	void	 post_bl_head(POST_ARGS);
 static	void	 post_bl_norm(POST_ARGS);
 static	void	 post_bx(POST_ARGS);
 static	void	 post_defaults(POST_ARGS);
 static	void	 post_display(POST_ARGS);
 static	void	 post_dd(POST_ARGS);
 static	void	 post_delim(POST_ARGS);
 static	void	 post_delim_nb(POST_ARGS);
 static	void	 post_dt(POST_ARGS);
 static	void	 post_em(POST_ARGS);
 static	void	 post_en(POST_ARGS);
 static	void	 post_er(POST_ARGS);
 static	void	 post_es(POST_ARGS);
 static	void	 post_eoln(POST_ARGS);
 static	void	 post_ex(POST_ARGS);
 static	void	 post_fa(POST_ARGS);
 static	void	 post_fl(POST_ARGS);
 static	void	 post_fn(POST_ARGS);
 static	void	 post_fname(POST_ARGS);
 static	void	 post_fo(POST_ARGS);
 static	void	 post_hyph(POST_ARGS);
 static	void	 post_it(POST_ARGS);
 static	void	 post_lb(POST_ARGS);
 static	void	 post_nd(POST_ARGS);
 static	void	 post_nm(POST_ARGS);
 static	void	 post_ns(POST_ARGS);
 static	void	 post_obsolete(POST_ARGS);
 static	void	 post_os(POST_ARGS);
 static	void	 post_par(POST_ARGS);
 static	void	 post_prevpar(POST_ARGS);
 static	void	 post_root(POST_ARGS);
 static	void	 post_rs(POST_ARGS);
 static	void	 post_rv(POST_ARGS);
 static	void	 post_section(POST_ARGS);
 static	void	 post_sh(POST_ARGS);
 static	void	 post_sh_head(POST_ARGS);
 static	void	 post_sh_name(POST_ARGS);
 static	void	 post_sh_see_also(POST_ARGS);
 static	void	 post_sh_authors(POST_ARGS);
 static	void	 post_sm(POST_ARGS);
 static	void	 post_st(POST_ARGS);
 static	void	 post_std(POST_ARGS);
 static	void	 post_sx(POST_ARGS);
 static	void	 post_tag(POST_ARGS);
 static	void	 post_tg(POST_ARGS);
 static	void	 post_useless(POST_ARGS);
 static	void	 post_xr(POST_ARGS);
 static	void	 post_xx(POST_ARGS);
 
 static	const v_post mdoc_valids[MDOC_MAX - MDOC_Dd] = {
 	post_dd,	/* Dd */
 	post_dt,	/* Dt */
 	post_os,	/* Os */
 	post_sh,	/* Sh */
 	post_section,	/* Ss */
 	post_par,	/* Pp */
 	post_display,	/* D1 */
 	post_display,	/* Dl */
 	post_display,	/* Bd */
 	NULL,		/* Ed */
 	post_bl,	/* Bl */
 	NULL,		/* El */
 	post_it,	/* It */
 	post_delim_nb,	/* Ad */
 	post_an,	/* An */
 	NULL,		/* Ap */
 	post_defaults,	/* Ar */
 	NULL,		/* Cd */
 	post_tag,	/* Cm */
 	post_tag,	/* Dv */
 	post_er,	/* Er */
 	post_tag,	/* Ev */
 	post_ex,	/* Ex */
 	post_fa,	/* Fa */
 	NULL,		/* Fd */
 	post_fl,	/* Fl */
 	post_fn,	/* Fn */
 	post_delim_nb,	/* Ft */
 	post_tag,	/* Ic */
 	post_delim_nb,	/* In */
 	post_tag,	/* Li */
 	post_nd,	/* Nd */
 	post_nm,	/* Nm */
 	post_delim_nb,	/* Op */
 	post_abort,	/* Ot */
 	post_defaults,	/* Pa */
 	post_rv,	/* Rv */
 	post_st,	/* St */
 	post_tag,	/* Va */
 	post_delim_nb,	/* Vt */
 	post_xr,	/* Xr */
 	NULL,		/* %A */
 	post_hyph,	/* %B */ /* FIXME: can be used outside Rs/Re. */
 	NULL,		/* %D */
 	NULL,		/* %I */
 	NULL,		/* %J */
 	post_hyph,	/* %N */
 	post_hyph,	/* %O */
 	NULL,		/* %P */
 	post_hyph,	/* %R */
 	post_hyph,	/* %T */ /* FIXME: can be used outside Rs/Re. */
 	NULL,		/* %V */
 	NULL,		/* Ac */
 	NULL,		/* Ao */
 	post_delim_nb,	/* Aq */
 	post_at,	/* At */
 	NULL,		/* Bc */
 	post_bf,	/* Bf */
 	NULL,		/* Bo */
 	NULL,		/* Bq */
 	post_xx,	/* Bsx */
 	post_bx,	/* Bx */
 	post_obsolete,	/* Db */
 	NULL,		/* Dc */
 	NULL,		/* Do */
 	NULL,		/* Dq */
 	NULL,		/* Ec */
 	NULL,		/* Ef */
 	post_em,	/* Em */
 	NULL,		/* Eo */
 	post_xx,	/* Fx */
 	post_tag,	/* Ms */
 	post_tag,	/* No */
 	post_ns,	/* Ns */
 	post_xx,	/* Nx */
 	post_xx,	/* Ox */
 	NULL,		/* Pc */
 	NULL,		/* Pf */
 	NULL,		/* Po */
 	post_delim_nb,	/* Pq */
 	NULL,		/* Qc */
 	post_delim_nb,	/* Ql */
 	NULL,		/* Qo */
 	post_delim_nb,	/* Qq */
 	NULL,		/* Re */
 	post_rs,	/* Rs */
 	NULL,		/* Sc */
 	NULL,		/* So */
 	post_delim_nb,	/* Sq */
 	post_sm,	/* Sm */
 	post_sx,	/* Sx */
 	post_em,	/* Sy */
 	post_useless,	/* Tn */
 	post_xx,	/* Ux */
 	NULL,		/* Xc */
 	NULL,		/* Xo */
 	post_fo,	/* Fo */
 	NULL,		/* Fc */
 	NULL,		/* Oo */
 	NULL,		/* Oc */
 	post_bk,	/* Bk */
 	NULL,		/* Ek */
 	post_eoln,	/* Bt */
 	post_obsolete,	/* Hf */
 	post_obsolete,	/* Fr */
 	post_eoln,	/* Ud */
 	post_lb,	/* Lb */
 	post_abort,	/* Lp */
 	post_delim_nb,	/* Lk */
 	post_defaults,	/* Mt */
 	post_delim_nb,	/* Brq */
 	NULL,		/* Bro */
 	NULL,		/* Brc */
 	NULL,		/* %C */
 	post_es,	/* Es */
 	post_en,	/* En */
 	post_xx,	/* Dx */
 	NULL,		/* %Q */
 	NULL,		/* %U */
 	NULL,		/* Ta */
 	post_tg,	/* Tg */
 };
 
 #define	RSORD_MAX 14 /* Number of `Rs' blocks. */
 
 static	const enum roff_tok rsord[RSORD_MAX] = {
 	MDOC__A,
 	MDOC__T,
 	MDOC__B,
 	MDOC__I,
 	MDOC__J,
 	MDOC__R,
 	MDOC__N,
 	MDOC__V,
 	MDOC__U,
 	MDOC__P,
 	MDOC__Q,
 	MDOC__C,
 	MDOC__D,
 	MDOC__O
 };
 
 static	const char * const secnames[SEC__MAX] = {
 	NULL,
 	"NAME",
 	"LIBRARY",
 	"SYNOPSIS",
 	"DESCRIPTION",
 	"CONTEXT",
 	"IMPLEMENTATION NOTES",
 	"RETURN VALUES",
 	"ENVIRONMENT",
 	"FILES",
 	"EXIT STATUS",
 	"EXAMPLES",
 	"DIAGNOSTICS",
 	"COMPATIBILITY",
 	"ERRORS",
 	"SEE ALSO",
 	"STANDARDS",
 	"HISTORY",
 	"AUTHORS",
 	"CAVEATS",
 	"BUGS",
 	"SECURITY CONSIDERATIONS",
 	NULL
 };
 
 static	int	  fn_prio = TAG_STRONG;
 
 
 /* Validate the subtree rooted at mdoc->last. */
 void
 mdoc_validate(struct roff_man *mdoc)
 {
 	struct roff_node *n, *np;
 	const v_post *p;
 
 	/*
 	 * Translate obsolete macros to modern macros first
 	 * such that later code does not need to look
 	 * for the obsolete versions.
 	 */
 
 	n = mdoc->last;
 	switch (n->tok) {
 	case MDOC_Lp:
 		n->tok = MDOC_Pp;
 		break;
 	case MDOC_Ot:
 		post_obsolete(mdoc);
 		n->tok = MDOC_Ft;
 		break;
 	default:
 		break;
 	}
 
 	/*
 	 * Iterate over all children, recursing into each one
 	 * in turn, depth-first.
 	 */
 
 	mdoc->last = mdoc->last->child;
 	while (mdoc->last != NULL) {
 		mdoc_validate(mdoc);
 		if (mdoc->last == n)
 			mdoc->last = mdoc->last->child;
 		else
 			mdoc->last = mdoc->last->next;
 	}
 
 	/* Finally validate the macro itself. */
 
 	mdoc->last = n;
 	mdoc->next = ROFF_NEXT_SIBLING;
 	switch (n->type) {
 	case ROFFT_TEXT:
 		np = n->parent;
 		if (n->sec != SEC_SYNOPSIS ||
 		    (np->tok != MDOC_Cd && np->tok != MDOC_Fd))
 			check_text(mdoc, n->line, n->pos, n->string);
 		if ((n->flags & NODE_NOFILL) == 0 &&
 		    (np->tok != MDOC_It || np->type != ROFFT_HEAD ||
 		     np->parent->parent->norm->Bl.type != LIST_diag))
 			check_text_em(mdoc, n->line, n->pos, n->string);
 		if (np->tok == MDOC_It || (np->type == ROFFT_BODY &&
 		    (np->tok == MDOC_Sh || np->tok == MDOC_Ss)))
 			check_toptext(mdoc, n->line, n->pos, n->string);
 		break;
 	case ROFFT_COMMENT:
 	case ROFFT_EQN:
 	case ROFFT_TBL:
 		break;
 	case ROFFT_ROOT:
 		post_root(mdoc);
 		break;
 	default:
 		check_args(mdoc, mdoc->last);
 
 		/*
 		 * Closing delimiters are not special at the
 		 * beginning of a block, opening delimiters
 		 * are not special at the end.
 		 */
 
 		if (n->child != NULL)
 			n->child->flags &= ~NODE_DELIMC;
 		if (n->last != NULL)
 			n->last->flags &= ~NODE_DELIMO;
 
 		/* Call the macro's postprocessor. */
 
 		if (n->tok < ROFF_MAX) {
 			roff_validate(mdoc);
 			break;
 		}
 
 		assert(n->tok >= MDOC_Dd && n->tok < MDOC_MAX);
 		p = mdoc_valids + (n->tok - MDOC_Dd);
 		if (*p)
 			(*p)(mdoc);
 		if (mdoc->last == n)
 			mdoc_state(mdoc, n);
 		break;
 	}
 }
 
 static void
 check_args(struct roff_man *mdoc, struct roff_node *n)
 {
 	int		 i;
 
 	if (NULL == n->args)
 		return;
 
 	assert(n->args->argc);
 	for (i = 0; i < (int)n->args->argc; i++)
 		check_argv(mdoc, n, &n->args->argv[i]);
 }
 
 static void
 check_argv(struct roff_man *mdoc, struct roff_node *n, struct mdoc_argv *v)
 {
 	int		 i;
 
 	for (i = 0; i < (int)v->sz; i++)
 		check_text(mdoc, v->line, v->pos, v->value[i]);
 }
 
 static void
 check_text(struct roff_man *mdoc, int ln, int pos, char *p)
 {
 	char		*cp;
 
 	if (mdoc->last->flags & NODE_NOFILL)
 		return;
 
 	for (cp = p; NULL != (p = strchr(p, '\t')); p++)
 		mandoc_msg(MANDOCERR_FI_TAB, ln, pos + (int)(p - cp), NULL);
 }
 
 static void
 check_text_em(struct roff_man *mdoc, int ln, int pos, char *p)
 {
 	const struct roff_node	*np, *nn;
 	char			*cp;
 
 	np = mdoc->last->prev;
 	nn = mdoc->last->next;
 
 	/* Look for em-dashes wrongly encoded as "--". */
 
 	for (cp = p; *cp != '\0'; cp++) {
 		if (cp[0] != '-' || cp[1] != '-')
 			continue;
 		cp++;
 
 		/* Skip input sequences of more than two '-'. */
 
 		if (cp[1] == '-') {
 			while (cp[1] == '-')
 				cp++;
 			continue;
 		}
 
 		/* Skip "--" directly attached to something else. */
 
 		if ((cp - p > 1 && cp[-2] != ' ') ||
 		    (cp[1] != '\0' && cp[1] != ' '))
 			continue;
 
 		/* Require a letter right before or right afterwards. */
 
 		if ((cp - p > 2 ?
 		     isalpha((unsigned char)cp[-3]) :
 		     np != NULL &&
 		     np->type == ROFFT_TEXT &&
 		     *np->string != '\0' &&
 		     isalpha((unsigned char)np->string[
 		       strlen(np->string) - 1])) ||
 		    (cp[1] != '\0' && cp[2] != '\0' ?
 		     isalpha((unsigned char)cp[2]) :
 		     nn != NULL &&
 		     nn->type == ROFFT_TEXT &&
 		     isalpha((unsigned char)*nn->string))) {
 			mandoc_msg(MANDOCERR_DASHDASH,
 			    ln, pos + (int)(cp - p) - 1, NULL);
 			break;
 		}
 	}
 }
 
 static void
 check_toptext(struct roff_man *mdoc, int ln, int pos, const char *p)
 {
 	const char	*cp, *cpr;
 
 	if (*p == '\0')
 		return;
 
 	if ((cp = strstr(p, "OpenBSD")) != NULL)
 		mandoc_msg(MANDOCERR_BX, ln, pos + (int)(cp - p), "Ox");
 	if ((cp = strstr(p, "NetBSD")) != NULL)
 		mandoc_msg(MANDOCERR_BX, ln, pos + (int)(cp - p), "Nx");
 	if ((cp = strstr(p, "FreeBSD")) != NULL)
 		mandoc_msg(MANDOCERR_BX, ln, pos + (int)(cp - p), "Fx");
 	if ((cp = strstr(p, "DragonFly")) != NULL)
 		mandoc_msg(MANDOCERR_BX, ln, pos + (int)(cp - p), "Dx");
 
 	cp = p;
 	while ((cp = strstr(cp + 1, "()")) != NULL) {
 		for (cpr = cp - 1; cpr >= p; cpr--)
 			if (*cpr != '_' && !isalnum((unsigned char)*cpr))
 				break;
 		if ((cpr < p || *cpr == ' ') && cpr + 1 < cp) {
 			cpr++;
 			mandoc_msg(MANDOCERR_FUNC, ln, pos + (int)(cpr - p),
 			    "%.*s()", (int)(cp - cpr), cpr);
 		}
 	}
 }
 
 static void
 post_abort(POST_ARGS)
 {
 	abort();
 }
 
 static void
 post_delim(POST_ARGS)
 {
 	const struct roff_node	*nch;
 	const char		*lc;
 	enum mdelim		 delim;
 	enum roff_tok		 tok;
 
 	tok = mdoc->last->tok;
 	nch = mdoc->last->last;
 	if (nch == NULL || nch->type != ROFFT_TEXT)
 		return;
 	lc = strchr(nch->string, '\0') - 1;
 	if (lc < nch->string)
 		return;
 	delim = mdoc_isdelim(lc);
 	if (delim == DELIM_NONE || delim == DELIM_OPEN)
 		return;
 	if (*lc == ')' && (tok == MDOC_Nd || tok == MDOC_Sh ||
 	    tok == MDOC_Ss || tok == MDOC_Fo))
 		return;
 
 	mandoc_msg(MANDOCERR_DELIM, nch->line,
 	    nch->pos + (int)(lc - nch->string), "%s%s %s", roff_name[tok],
 	    nch == mdoc->last->child ? "" : " ...", nch->string);
 }
 
 static void
 post_delim_nb(POST_ARGS)
 {
 	const struct roff_node	*nch;
 	const char		*lc, *cp;
 	int			 nw;
 	enum mdelim		 delim;
 	enum roff_tok		 tok;
 
 	/*
 	 * Find candidates: at least two bytes,
 	 * the last one a closing or middle delimiter.
 	 */
 
 	tok = mdoc->last->tok;
 	nch = mdoc->last->last;
 	if (nch == NULL || nch->type != ROFFT_TEXT)
 		return;
 	lc = strchr(nch->string, '\0') - 1;
 	if (lc <= nch->string)
 		return;
 	delim = mdoc_isdelim(lc);
 	if (delim == DELIM_NONE || delim == DELIM_OPEN)
 		return;
 
 	/*
 	 * Reduce false positives by allowing various cases.
 	 */
 
 	/* Escaped delimiters. */
 	if (lc > nch->string + 1 && lc[-2] == '\\' &&
 	    (lc[-1] == '&' || lc[-1] == 'e'))
 		return;
 
 	/* Specific byte sequences. */
 	switch (*lc) {
 	case ')':
 		for (cp = lc; cp >= nch->string; cp--)
 			if (*cp == '(')
 				return;
 		break;
 	case '.':
 		if (lc > nch->string + 1 && lc[-2] == '.' && lc[-1] == '.')
 			return;
 		if (lc[-1] == '.')
 			return;
 		break;
 	case ';':
 		if (tok == MDOC_Vt)
 			return;
 		break;
 	case '?':
 		if (lc[-1] == '?')
 			return;
 		break;
 	case ']':
 		for (cp = lc; cp >= nch->string; cp--)
 			if (*cp == '[')
 				return;
 		break;
 	case '|':
 		if (lc == nch->string + 1 && lc[-1] == '|')
 			return;
 	default:
 		break;
 	}
 
 	/* Exactly two non-alphanumeric bytes. */
 	if (lc == nch->string + 1 && !isalnum((unsigned char)lc[-1]))
 		return;
 
 	/* At least three alphabetic words with a sentence ending. */
 	if (strchr("!.:?", *lc) != NULL && (tok == MDOC_Em ||
 	    tok == MDOC_Li || tok == MDOC_Pq || tok == MDOC_Sy)) {
 		nw = 0;
 		for (cp = lc - 1; cp >= nch->string; cp--) {
 			if (*cp == ' ') {
 				nw++;
 				if (cp > nch->string && cp[-1] == ',')
 					cp--;
 			} else if (isalpha((unsigned int)*cp)) {
 				if (nw > 1)
 					return;
 			} else
 				break;
 		}
 	}
 
 	mandoc_msg(MANDOCERR_DELIM_NB, nch->line,
 	    nch->pos + (int)(lc - nch->string), "%s%s %s", roff_name[tok],
 	    nch == mdoc->last->child ? "" : " ...", nch->string);
 }
 
 static void
 post_bl_norm(POST_ARGS)
 {
 	struct roff_node *n;
 	struct mdoc_argv *argv, *wa;
 	int		  i;
 	enum mdocargt	  mdoclt;
 	enum mdoc_list	  lt;
 
 	n = mdoc->last->parent;
 	n->norm->Bl.type = LIST__NONE;
 
 	/*
 	 * First figure out which kind of list to use: bind ourselves to
 	 * the first mentioned list type and warn about any remaining
 	 * ones.  If we find no list type, we default to LIST_item.
 	 */
 
 	wa = (n->args == NULL) ? NULL : n->args->argv;
 	mdoclt = MDOC_ARG_MAX;
 	for (i = 0; n->args && i < (int)n->args->argc; i++) {
 		argv = n->args->argv + i;
 		lt = LIST__NONE;
 		switch (argv->arg) {
 		/* Set list types. */
 		case MDOC_Bullet:
 			lt = LIST_bullet;
 			break;
 		case MDOC_Dash:
 			lt = LIST_dash;
 			break;
 		case MDOC_Enum:
 			lt = LIST_enum;
 			break;
 		case MDOC_Hyphen:
 			lt = LIST_hyphen;
 			break;
 		case MDOC_Item:
 			lt = LIST_item;
 			break;
 		case MDOC_Tag:
 			lt = LIST_tag;
 			break;
 		case MDOC_Diag:
 			lt = LIST_diag;
 			break;
 		case MDOC_Hang:
 			lt = LIST_hang;
 			break;
 		case MDOC_Ohang:
 			lt = LIST_ohang;
 			break;
 		case MDOC_Inset:
 			lt = LIST_inset;
 			break;
 		case MDOC_Column:
 			lt = LIST_column;
 			break;
 		/* Set list arguments. */
 		case MDOC_Compact:
 			if (n->norm->Bl.comp)
 				mandoc_msg(MANDOCERR_ARG_REP,
 				    argv->line, argv->pos, "Bl -compact");
 			n->norm->Bl.comp = 1;
 			break;
 		case MDOC_Width:
 			wa = argv;
 			if (0 == argv->sz) {
 				mandoc_msg(MANDOCERR_ARG_EMPTY,
 				    argv->line, argv->pos, "Bl -width");
 				n->norm->Bl.width = "0n";
 				break;
 			}
 			if (NULL != n->norm->Bl.width)
 				mandoc_msg(MANDOCERR_ARG_REP,
 				    argv->line, argv->pos,
 				    "Bl -width %s", argv->value[0]);
 			rewrite_macro2len(mdoc, argv->value);
 			n->norm->Bl.width = argv->value[0];
 			break;
 		case MDOC_Offset:
 			if (0 == argv->sz) {
 				mandoc_msg(MANDOCERR_ARG_EMPTY,
 				    argv->line, argv->pos, "Bl -offset");
 				break;
 			}
 			if (NULL != n->norm->Bl.offs)
 				mandoc_msg(MANDOCERR_ARG_REP,
 				    argv->line, argv->pos,
 				    "Bl -offset %s", argv->value[0]);
 			rewrite_macro2len(mdoc, argv->value);
 			n->norm->Bl.offs = argv->value[0];
 			break;
 		default:
 			continue;
 		}
 		if (LIST__NONE == lt)
 			continue;
 		mdoclt = argv->arg;
 
 		/* Check: multiple list types. */
 
 		if (LIST__NONE != n->norm->Bl.type) {
 			mandoc_msg(MANDOCERR_BL_REP, n->line, n->pos,
 			    "Bl -%s", mdoc_argnames[argv->arg]);
 			continue;
 		}
 
 		/* The list type should come first. */
 
 		if (n->norm->Bl.width ||
 		    n->norm->Bl.offs ||
 		    n->norm->Bl.comp)
 			mandoc_msg(MANDOCERR_BL_LATETYPE,
 			    n->line, n->pos, "Bl -%s",
 			    mdoc_argnames[n->args->argv[0].arg]);
 
 		n->norm->Bl.type = lt;
 		if (LIST_column == lt) {
 			n->norm->Bl.ncols = argv->sz;
 			n->norm->Bl.cols = (void *)argv->value;
 		}
 	}
 
 	/* Allow lists to default to LIST_item. */
 
 	if (LIST__NONE == n->norm->Bl.type) {
 		mandoc_msg(MANDOCERR_BL_NOTYPE, n->line, n->pos, "Bl");
 		n->norm->Bl.type = LIST_item;
 		mdoclt = MDOC_Item;
 	}
 
 	/*
 	 * Validate the width field.  Some list types don't need width
 	 * types and should be warned about them.  Others should have it
 	 * and must also be warned.  Yet others have a default and need
 	 * no warning.
 	 */
 
 	switch (n->norm->Bl.type) {
 	case LIST_tag:
 		if (n->norm->Bl.width == NULL)
 			mandoc_msg(MANDOCERR_BL_NOWIDTH,
 			    n->line, n->pos, "Bl -tag");
 		break;
 	case LIST_column:
 	case LIST_diag:
 	case LIST_ohang:
 	case LIST_inset:
 	case LIST_item:
 		if (n->norm->Bl.width != NULL)
 			mandoc_msg(MANDOCERR_BL_SKIPW, wa->line, wa->pos,
 			    "Bl -%s", mdoc_argnames[mdoclt]);
 		n->norm->Bl.width = NULL;
 		break;
 	case LIST_bullet:
 	case LIST_dash:
 	case LIST_hyphen:
 		if (n->norm->Bl.width == NULL)
 			n->norm->Bl.width = "2n";
 		break;
 	case LIST_enum:
 		if (n->norm->Bl.width == NULL)
 			n->norm->Bl.width = "3n";
 		break;
 	default:
 		break;
 	}
 }
 
 static void
 post_bd(POST_ARGS)
 {
 	struct roff_node *n;
 	struct mdoc_argv *argv;
 	int		  i;
 	enum mdoc_disp	  dt;
 
 	n = mdoc->last;
 	for (i = 0; n->args && i < (int)n->args->argc; i++) {
 		argv = n->args->argv + i;
 		dt = DISP__NONE;
 
 		switch (argv->arg) {
 		case MDOC_Centred:
 			dt = DISP_centered;
 			break;
 		case MDOC_Ragged:
 			dt = DISP_ragged;
 			break;
 		case MDOC_Unfilled:
 			dt = DISP_unfilled;
 			break;
 		case MDOC_Filled:
 			dt = DISP_filled;
 			break;
 		case MDOC_Literal:
 			dt = DISP_literal;
 			break;
 		case MDOC_File:
 			mandoc_msg(MANDOCERR_BD_FILE, n->line, n->pos, NULL);
 			break;
 		case MDOC_Offset:
 			if (0 == argv->sz) {
 				mandoc_msg(MANDOCERR_ARG_EMPTY,
 				    argv->line, argv->pos, "Bd -offset");
 				break;
 			}
 			if (NULL != n->norm->Bd.offs)
 				mandoc_msg(MANDOCERR_ARG_REP,
 				    argv->line, argv->pos,
 				    "Bd -offset %s", argv->value[0]);
 			rewrite_macro2len(mdoc, argv->value);
 			n->norm->Bd.offs = argv->value[0];
 			break;
 		case MDOC_Compact:
 			if (n->norm->Bd.comp)
 				mandoc_msg(MANDOCERR_ARG_REP,
 				    argv->line, argv->pos, "Bd -compact");
 			n->norm->Bd.comp = 1;
 			break;
 		default:
 			abort();
 		}
 		if (DISP__NONE == dt)
 			continue;
 
 		if (DISP__NONE == n->norm->Bd.type)
 			n->norm->Bd.type = dt;
 		else
 			mandoc_msg(MANDOCERR_BD_REP, n->line, n->pos,
 			    "Bd -%s", mdoc_argnames[argv->arg]);
 	}
 
 	if (DISP__NONE == n->norm->Bd.type) {
 		mandoc_msg(MANDOCERR_BD_NOTYPE, n->line, n->pos, "Bd");
 		n->norm->Bd.type = DISP_ragged;
 	}
 }
 
 /*
  * Stand-alone line macros.
  */
 
 static void
 post_an_norm(POST_ARGS)
 {
 	struct roff_node *n;
 	struct mdoc_argv *argv;
 	size_t	 i;
 
 	n = mdoc->last;
 	if (n->args == NULL)
 		return;
 
 	for (i = 1; i < n->args->argc; i++) {
 		argv = n->args->argv + i;
 		mandoc_msg(MANDOCERR_AN_REP, argv->line, argv->pos,
 		    "An -%s", mdoc_argnames[argv->arg]);
 	}
 
 	argv = n->args->argv;
 	if (argv->arg == MDOC_Split)
 		n->norm->An.auth = AUTH_split;
 	else if (argv->arg == MDOC_Nosplit)
 		n->norm->An.auth = AUTH_nosplit;
 	else
 		abort();
 }
 
 static void
 post_eoln(POST_ARGS)
 {
 	struct roff_node	*n;
 
 	post_useless(mdoc);
 	n = mdoc->last;
 	if (n->child != NULL)
 		mandoc_msg(MANDOCERR_ARG_SKIP, n->line,
 		    n->pos, "%s %s", roff_name[n->tok], n->child->string);
 
 	while (n->child != NULL)
 		roff_node_delete(mdoc, n->child);
 
 	roff_word_alloc(mdoc, n->line, n->pos, n->tok == MDOC_Bt ?
 	    "is currently in beta test." : "currently under development.");
 	mdoc->last->flags |= NODE_EOS | NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static int
 build_list(struct roff_man *mdoc, int tok)
 {
 	struct roff_node	*n;
 	int			 ic;
 
 	n = mdoc->last->next;
 	for (ic = 1;; ic++) {
 		roff_elem_alloc(mdoc, n->line, n->pos, tok);
 		mdoc->last->flags |= NODE_NOSRC;
 		roff_node_relink(mdoc, n);
 		n = mdoc->last = mdoc->last->parent;
 		mdoc->next = ROFF_NEXT_SIBLING;
 		if (n->next == NULL)
 			return ic;
 		if (ic > 1 || n->next->next != NULL) {
 			roff_word_alloc(mdoc, n->line, n->pos, ",");
 			mdoc->last->flags |= NODE_DELIMC | NODE_NOSRC;
 		}
 		n = mdoc->last->next;
 		if (n->next == NULL) {
 			roff_word_alloc(mdoc, n->line, n->pos, "and");
 			mdoc->last->flags |= NODE_NOSRC;
 		}
 	}
 }
 
 static void
 post_ex(POST_ARGS)
 {
 	struct roff_node	*n;
 	int			 ic;
 
 	post_std(mdoc);
 
 	n = mdoc->last;
 	mdoc->next = ROFF_NEXT_CHILD;
 	roff_word_alloc(mdoc, n->line, n->pos, "The");
 	mdoc->last->flags |= NODE_NOSRC;
 
 	if (mdoc->last->next != NULL)
 		ic = build_list(mdoc, MDOC_Nm);
 	else if (mdoc->meta.name != NULL) {
 		roff_elem_alloc(mdoc, n->line, n->pos, MDOC_Nm);
 		mdoc->last->flags |= NODE_NOSRC;
 		roff_word_alloc(mdoc, n->line, n->pos, mdoc->meta.name);
 		mdoc->last->flags |= NODE_NOSRC;
 		mdoc->last = mdoc->last->parent;
 		mdoc->next = ROFF_NEXT_SIBLING;
 		ic = 1;
 	} else {
 		mandoc_msg(MANDOCERR_EX_NONAME, n->line, n->pos, "Ex");
 		ic = 0;
 	}
 
 	roff_word_alloc(mdoc, n->line, n->pos,
 	    ic > 1 ? "utilities exit\\~0" : "utility exits\\~0");
 	mdoc->last->flags |= NODE_NOSRC;
 	roff_word_alloc(mdoc, n->line, n->pos,
 	    "on success, and\\~>0 if an error occurs.");
 	mdoc->last->flags |= NODE_EOS | NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_lb(POST_ARGS)
 {
 	struct roff_node	*n;
 	const char		*p;
 
 	post_delim_nb(mdoc);
 
 	n = mdoc->last;
 	assert(n->child->type == ROFFT_TEXT);
 	mdoc->next = ROFF_NEXT_CHILD;
 
 	if ((p = mdoc_a2lib(n->child->string)) != NULL) {
 		n->child->flags |= NODE_NOPRT;
 		roff_word_alloc(mdoc, n->line, n->pos, p);
 		mdoc->last->flags = NODE_NOSRC;
 		mdoc->last = n;
 		return;
 	}
 
 	mandoc_msg(MANDOCERR_LB_BAD, n->child->line,
 	    n->child->pos, "Lb %s", n->child->string);
 
 	roff_word_alloc(mdoc, n->line, n->pos, "library");
 	mdoc->last->flags = NODE_NOSRC;
 	roff_word_alloc(mdoc, n->line, n->pos, "\\(lq");
 	mdoc->last->flags = NODE_DELIMO | NODE_NOSRC;
 	mdoc->last = mdoc->last->next;
 	roff_word_alloc(mdoc, n->line, n->pos, "\\(rq");
 	mdoc->last->flags = NODE_DELIMC | NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_rv(POST_ARGS)
 {
 	struct roff_node	*n;
 	int			 ic;
 
 	post_std(mdoc);
 
 	n = mdoc->last;
 	mdoc->next = ROFF_NEXT_CHILD;
 	if (n->child != NULL) {
 		roff_word_alloc(mdoc, n->line, n->pos, "The");
 		mdoc->last->flags |= NODE_NOSRC;
 		ic = build_list(mdoc, MDOC_Fn);
 		roff_word_alloc(mdoc, n->line, n->pos,
 		    ic > 1 ? "functions return" : "function returns");
 		mdoc->last->flags |= NODE_NOSRC;
 		roff_word_alloc(mdoc, n->line, n->pos,
 		    "the value\\~0 if successful;");
 	} else
 		roff_word_alloc(mdoc, n->line, n->pos, "Upon successful "
 		    "completion, the value\\~0 is returned;");
 	mdoc->last->flags |= NODE_NOSRC;
 
 	roff_word_alloc(mdoc, n->line, n->pos, "otherwise "
 	    "the value\\~\\-1 is returned and the global variable");
 	mdoc->last->flags |= NODE_NOSRC;
 	roff_elem_alloc(mdoc, n->line, n->pos, MDOC_Va);
 	mdoc->last->flags |= NODE_NOSRC;
 	roff_word_alloc(mdoc, n->line, n->pos, "errno");
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = mdoc->last->parent;
 	mdoc->next = ROFF_NEXT_SIBLING;
 	roff_word_alloc(mdoc, n->line, n->pos,
 	    "is set to indicate the error.");
 	mdoc->last->flags |= NODE_EOS | NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_std(POST_ARGS)
 {
 	struct roff_node *n;
 
 	post_delim(mdoc);
 
 	n = mdoc->last;
 	if (n->args && n->args->argc == 1)
 		if (n->args->argv[0].arg == MDOC_Std)
 			return;
 
 	mandoc_msg(MANDOCERR_ARG_STD, n->line, n->pos,
 	    "%s", roff_name[n->tok]);
 }
 
 static void
 post_st(POST_ARGS)
 {
 	struct roff_node	 *n, *nch;
 	const char		 *p;
 
 	n = mdoc->last;
 	nch = n->child;
 	assert(nch->type == ROFFT_TEXT);
 
 	if ((p = mdoc_a2st(nch->string)) == NULL) {
 		mandoc_msg(MANDOCERR_ST_BAD,
 		    nch->line, nch->pos, "St %s", nch->string);
 		roff_node_delete(mdoc, n);
 		return;
 	}
 
 	nch->flags |= NODE_NOPRT;
 	mdoc->next = ROFF_NEXT_CHILD;
 	roff_word_alloc(mdoc, nch->line, nch->pos, p);
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last= n;
 }
 
 static void
 post_tg(POST_ARGS)
 {
 	struct roff_node *n;	/* The .Tg node. */
 	struct roff_node *nch;	/* The first child of the .Tg node. */
 	struct roff_node *nn;   /* The next node after the .Tg node. */
 	struct roff_node *np;	/* The parent of the next node. */
 	struct roff_node *nt;	/* The TEXT node containing the tag. */
 	size_t		  len;	/* The number of bytes in the tag. */
 
 	/* Find the next node. */
 	n = mdoc->last;
 	for (nn = n; nn != NULL; nn = nn->parent) {
 		if (nn->next != NULL) {
 			nn = nn->next;
 			break;
 		}
 	}
 
 	/* Find the tag. */
 	nt = nch = n->child;
 	if (nch == NULL && nn != NULL && nn->child != NULL &&
 	    nn->child->type == ROFFT_TEXT)
 		nt = nn->child;
 
 	/* Validate the tag. */
 	if (nt == NULL || *nt->string == '\0')
 		mandoc_msg(MANDOCERR_MACRO_EMPTY, n->line, n->pos, "Tg");
 	if (nt == NULL) {
 		roff_node_delete(mdoc, n);
 		return;
 	}
 	len = strcspn(nt->string, " \t\\");
 	if (nt->string[len] != '\0')
 		mandoc_msg(MANDOCERR_TG_SPC, nt->line,
 		    nt->pos + len, "Tg %s", nt->string);
 
 	/* Keep only the first argument. */
 	if (nch != NULL && nch->next != NULL) {
 		mandoc_msg(MANDOCERR_ARG_EXCESS, nch->next->line,
 		    nch->next->pos, "Tg ... %s", nch->next->string);
 		while (nch->next != NULL)
 			roff_node_delete(mdoc, nch->next);
 	}
 
 	/* Drop the macro if the first argument is invalid. */
 	if (len == 0 || nt->string[len] != '\0') {
 		roff_node_delete(mdoc, n);
 		return;
 	}
 
 	/* By default, tag the .Tg node itself. */
 	if (nn == NULL || nn->flags & NODE_ID)
 		nn = n;
 
 	/* Explicit tagging of specific macros. */
 	switch (nn->tok) {
 	case MDOC_Sh:
 	case MDOC_Ss:
 	case MDOC_Fo:
 		nn = nn->head->child == NULL ? n : nn->head;
 		break;
 	case MDOC_It:
 		np = nn->parent;
 		while (np->tok != MDOC_Bl)
 			np = np->parent;
 		switch (np->norm->Bl.type) {
 		case LIST_column:
 			break;
 		case LIST_diag:
 		case LIST_hang:
 		case LIST_inset:
 		case LIST_ohang:
 		case LIST_tag:
 			nn = nn->head;
 			break;
 		case LIST_bullet:
 		case LIST_dash:
 		case LIST_enum:
 		case LIST_hyphen:
 		case LIST_item:
 			nn = nn->body->child == NULL ? n : nn->body;
 			break;
 		default:
 			abort();
 		}
 		break;
 	case MDOC_Bd:
 	case MDOC_Bl:
 	case MDOC_D1:
 	case MDOC_Dl:
 		nn = nn->body->child == NULL ? n : nn->body;
 		break;
 	case MDOC_Pp:
 		break;
 	case MDOC_Cm:
 	case MDOC_Dv:
 	case MDOC_Em:
 	case MDOC_Er:
 	case MDOC_Ev:
 	case MDOC_Fl:
 	case MDOC_Fn:
 	case MDOC_Ic:
 	case MDOC_Li:
 	case MDOC_Ms:
 	case MDOC_No:
 	case MDOC_Sy:
 		if (nn->child == NULL)
 			nn = n;
 		break;
 	default:
 		nn = n;
 		break;
 	}
 	tag_put(nt->string, TAG_MANUAL, nn);
 	if (nn != n)
 		n->flags |= NODE_NOPRT;
 }
 
 static void
 post_obsolete(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	if (n->type == ROFFT_ELEM || n->type == ROFFT_BLOCK)
 		mandoc_msg(MANDOCERR_MACRO_OBS, n->line, n->pos,
 		    "%s", roff_name[n->tok]);
 }
 
 static void
 post_useless(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	mandoc_msg(MANDOCERR_MACRO_USELESS, n->line, n->pos,
 	    "%s", roff_name[n->tok]);
 }
 
 /*
  * Block macros.
  */
 
 static void
 post_bf(POST_ARGS)
 {
 	struct roff_node *np, *nch;
 
 	/*
 	 * Unlike other data pointers, these are "housed" by the HEAD
 	 * element, which contains the goods.
 	 */
 
 	np = mdoc->last;
 	if (np->type != ROFFT_HEAD)
 		return;
 
 	assert(np->parent->type == ROFFT_BLOCK);
 	assert(np->parent->tok == MDOC_Bf);
 
 	/* Check the number of arguments. */
 
 	nch = np->child;
 	if (np->parent->args == NULL) {
 		if (nch == NULL) {
 			mandoc_msg(MANDOCERR_BF_NOFONT,
 			    np->line, np->pos, "Bf");
 			return;
 		}
 		nch = nch->next;
 	}
 	if (nch != NULL)
 		mandoc_msg(MANDOCERR_ARG_EXCESS,
 		    nch->line, nch->pos, "Bf ... %s", nch->string);
 
 	/* Extract argument into data. */
 
 	if (np->parent->args != NULL) {
 		switch (np->parent->args->argv[0].arg) {
 		case MDOC_Emphasis:
 			np->norm->Bf.font = FONT_Em;
 			break;
 		case MDOC_Literal:
 			np->norm->Bf.font = FONT_Li;
 			break;
 		case MDOC_Symbolic:
 			np->norm->Bf.font = FONT_Sy;
 			break;
 		default:
 			abort();
 		}
 		return;
 	}
 
 	/* Extract parameter into data. */
 
 	if ( ! strcmp(np->child->string, "Em"))
 		np->norm->Bf.font = FONT_Em;
 	else if ( ! strcmp(np->child->string, "Li"))
 		np->norm->Bf.font = FONT_Li;
 	else if ( ! strcmp(np->child->string, "Sy"))
 		np->norm->Bf.font = FONT_Sy;
 	else
 		mandoc_msg(MANDOCERR_BF_BADFONT, np->child->line,
 		    np->child->pos, "Bf %s", np->child->string);
 }
 
 static void
 post_fname(POST_ARGS)
 {
 	struct roff_node	*n, *nch;
 	const char		*cp;
 	size_t			 pos;
 
 	n = mdoc->last;
 	nch = n->child;
 	cp = nch->string;
 	if (*cp == '(') {
 		if (cp[strlen(cp + 1)] == ')')
 			return;
 		pos = 0;
 	} else {
 		pos = strcspn(cp, "()");
 		if (cp[pos] == '\0') {
 			if (n->sec == SEC_DESCRIPTION ||
 			    n->sec == SEC_CUSTOM)
 				tag_put(NULL, fn_prio++, n);
 			return;
 		}
 	}
 	mandoc_msg(MANDOCERR_FN_PAREN, nch->line, nch->pos + pos, "%s", cp);
 }
 
 static void
 post_fn(POST_ARGS)
 {
 	post_fname(mdoc);
 	post_fa(mdoc);
 }
 
 static void
 post_fo(POST_ARGS)
 {
 	const struct roff_node	*n;
 
 	n = mdoc->last;
 
 	if (n->type != ROFFT_HEAD)
 		return;
 
 	if (n->child == NULL) {
 		mandoc_msg(MANDOCERR_FO_NOHEAD, n->line, n->pos, "Fo");
 		return;
 	}
 	if (n->child != n->last) {
 		mandoc_msg(MANDOCERR_ARG_EXCESS,
 		    n->child->next->line, n->child->next->pos,
 		    "Fo ... %s", n->child->next->string);
 		while (n->child != n->last)
 			roff_node_delete(mdoc, n->last);
 	} else
 		post_delim(mdoc);
 
 	post_fname(mdoc);
 }
 
 static void
 post_fa(POST_ARGS)
 {
 	const struct roff_node *n;
 	const char *cp;
 
 	for (n = mdoc->last->child; n != NULL; n = n->next) {
 		for (cp = n->string; *cp != '\0'; cp++) {
 			/* Ignore callbacks and alterations. */
 			if (*cp == '(' || *cp == '{')
 				break;
 			if (*cp != ',')
 				continue;
 			mandoc_msg(MANDOCERR_FA_COMMA, n->line,
 			    n->pos + (int)(cp - n->string), "%s", n->string);
 			break;
 		}
 	}
 	post_delim_nb(mdoc);
 }
 
 static void
 post_nm(POST_ARGS)
 {
 	struct roff_node	*n;
 
 	n = mdoc->last;
 
 	if (n->sec == SEC_NAME && n->child != NULL &&
 	    n->child->type == ROFFT_TEXT && mdoc->meta.msec != NULL)
 		mandoc_xr_add(mdoc->meta.msec, n->child->string, -1, -1);
 
 	if (n->last != NULL && n->last->tok == MDOC_Pp)
 		roff_node_relink(mdoc, n->last);
 
 	if (mdoc->meta.name == NULL)
 		deroff(&mdoc->meta.name, n);
 
 	if (mdoc->meta.name == NULL ||
 	    (mdoc->lastsec == SEC_NAME && n->child == NULL))
 		mandoc_msg(MANDOCERR_NM_NONAME, n->line, n->pos, "Nm");
 
 	switch (n->type) {
 	case ROFFT_ELEM:
 		post_delim_nb(mdoc);
 		break;
 	case ROFFT_HEAD:
 		post_delim(mdoc);
 		break;
 	default:
 		return;
 	}
 
 	if ((n->child != NULL && n->child->type == ROFFT_TEXT) ||
 	    mdoc->meta.name == NULL)
 		return;
 
 	mdoc->next = ROFF_NEXT_CHILD;
 	roff_word_alloc(mdoc, n->line, n->pos, mdoc->meta.name);
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_nd(POST_ARGS)
 {
 	struct roff_node	*n;
 
 	n = mdoc->last;
 
 	if (n->type != ROFFT_BODY)
 		return;
 
 	if (n->sec != SEC_NAME)
 		mandoc_msg(MANDOCERR_ND_LATE, n->line, n->pos, "Nd");
 
 	if (n->child == NULL)
 		mandoc_msg(MANDOCERR_ND_EMPTY, n->line, n->pos, "Nd");
 	else
 		post_delim(mdoc);
 
 	post_hyph(mdoc);
 }
 
 static void
 post_display(POST_ARGS)
 {
 	struct roff_node *n, *np;
 
 	n = mdoc->last;
 	switch (n->type) {
 	case ROFFT_BODY:
 		if (n->end != ENDBODY_NOT) {
 			if (n->tok == MDOC_Bd &&
 			    n->body->parent->args == NULL)
 				roff_node_delete(mdoc, n);
 		} else if (n->child == NULL)
 			mandoc_msg(MANDOCERR_BLK_EMPTY, n->line, n->pos,
 			    "%s", roff_name[n->tok]);
 		else if (n->tok == MDOC_D1)
 			post_hyph(mdoc);
 		break;
 	case ROFFT_BLOCK:
 		if (n->tok == MDOC_Bd) {
 			if (n->args == NULL) {
 				mandoc_msg(MANDOCERR_BD_NOARG,
 				    n->line, n->pos, "Bd");
 				mdoc->next = ROFF_NEXT_SIBLING;
 				while (n->body->child != NULL)
 					roff_node_relink(mdoc,
 					    n->body->child);
 				roff_node_delete(mdoc, n);
 				break;
 			}
 			post_bd(mdoc);
 			post_prevpar(mdoc);
 		}
 		for (np = n->parent; np != NULL; np = np->parent) {
 			if (np->type == ROFFT_BLOCK && np->tok == MDOC_Bd) {
 				mandoc_msg(MANDOCERR_BD_NEST, n->line,
 				    n->pos, "%s in Bd", roff_name[n->tok]);
 				break;
 			}
 		}
 		break;
 	default:
 		break;
 	}
 }
 
 static void
 post_defaults(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	if (n->child != NULL) {
 		post_delim_nb(mdoc);
 		return;
 	}
 	mdoc->next = ROFF_NEXT_CHILD;
 	switch (n->tok) {
 	case MDOC_Ar:
 		roff_word_alloc(mdoc, n->line, n->pos, "file");
 		mdoc->last->flags |= NODE_NOSRC;
 		roff_word_alloc(mdoc, n->line, n->pos, "...");
 		break;
 	case MDOC_Pa:
 	case MDOC_Mt:
 		roff_word_alloc(mdoc, n->line, n->pos, "~");
 		break;
 	default:
 		abort();
 	}
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_at(POST_ARGS)
 {
 	struct roff_node	*n, *nch;
 	const char		*att;
 
 	n = mdoc->last;
 	nch = n->child;
 
 	/*
 	 * If we have a child, look it up in the standard keys.  If a
 	 * key exist, use that instead of the child; if it doesn't,
 	 * prefix "AT&T UNIX " to the existing data.
 	 */
 
 	att = NULL;
 	if (nch != NULL && ((att = mdoc_a2att(nch->string)) == NULL))
 		mandoc_msg(MANDOCERR_AT_BAD,
 		    nch->line, nch->pos, "At %s", nch->string);
 
 	mdoc->next = ROFF_NEXT_CHILD;
 	if (att != NULL) {
 		roff_word_alloc(mdoc, nch->line, nch->pos, att);
 		nch->flags |= NODE_NOPRT;
 	} else
 		roff_word_alloc(mdoc, n->line, n->pos, "AT&T UNIX");
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_an(POST_ARGS)
 {
 	struct roff_node *np, *nch;
 
 	post_an_norm(mdoc);
 
 	np = mdoc->last;
 	nch = np->child;
 	if (np->norm->An.auth == AUTH__NONE) {
 		if (nch == NULL)
 			mandoc_msg(MANDOCERR_MACRO_EMPTY,
 			    np->line, np->pos, "An");
 		else
 			post_delim_nb(mdoc);
 	} else if (nch != NULL)
 		mandoc_msg(MANDOCERR_ARG_EXCESS,
 		    nch->line, nch->pos, "An ... %s", nch->string);
 }
 
 static void
 post_em(POST_ARGS)
 {
 	post_tag(mdoc);
 	tag_put(NULL, TAG_FALLBACK, mdoc->last);
 }
 
 static void
 post_en(POST_ARGS)
 {
 	post_obsolete(mdoc);
 	if (mdoc->last->type == ROFFT_BLOCK)
 		mdoc->last->norm->Es = mdoc->last_es;
 }
 
 static void
 post_er(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	if (n->sec == SEC_ERRORS &&
 	    (n->parent->tok == MDOC_It ||
 	     (n->parent->tok == MDOC_Bq &&
 	      n->parent->parent->parent->tok == MDOC_It)))
 		tag_put(NULL, TAG_STRONG, n);
 	post_delim_nb(mdoc);
 }
 
 static void
 post_tag(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	if ((n->prev == NULL ||
 	     (n->prev->type == ROFFT_TEXT &&
 	      strcmp(n->prev->string, "|") == 0)) &&
 	    (n->parent->tok == MDOC_It ||
 	     (n->parent->tok == MDOC_Xo &&
 	      n->parent->parent->prev == NULL &&
 	      n->parent->parent->parent->tok == MDOC_It)))
 		tag_put(NULL, TAG_STRONG, n);
 	post_delim_nb(mdoc);
 }
 
 static void
 post_es(POST_ARGS)
 {
 	post_obsolete(mdoc);
 	mdoc->last_es = mdoc->last;
 }
 
 static void
 post_fl(POST_ARGS)
 {
 	struct roff_node	*n;
 	char			*cp;
 
 	/*
 	 * Transform ".Fl Fl long" to ".Fl \-long",
 	 * resulting for example in better HTML output.
 	 */
 
 	n = mdoc->last;
 	if (n->prev != NULL && n->prev->tok == MDOC_Fl &&
 	    n->prev->child == NULL && n->child != NULL &&
 	    (n->flags & NODE_LINE) == 0) {
 		mandoc_asprintf(&cp, "\\-%s", n->child->string);
 		free(n->child->string);
 		n->child->string = cp;
 		roff_node_delete(mdoc, n->prev);
 	}
 	post_tag(mdoc);
 }
 
 static void
 post_xx(POST_ARGS)
 {
 	struct roff_node	*n;
 	const char		*os;
 	char			*v;
 
 	post_delim_nb(mdoc);
 
 	n = mdoc->last;
 	switch (n->tok) {
 	case MDOC_Bsx:
 		os = "BSD/OS";
 		break;
 	case MDOC_Dx:
 		os = "DragonFly";
 		break;
 	case MDOC_Fx:
 		os = "FreeBSD";
 		break;
 	case MDOC_Nx:
 		os = "NetBSD";
 		if (n->child == NULL)
 			break;
 		v = n->child->string;
 		if ((v[0] != '0' && v[0] != '1') || v[1] != '.' ||
 		    v[2] < '0' || v[2] > '9' ||
 		    v[3] < 'a' || v[3] > 'z' || v[4] != '\0')
 			break;
 		n->child->flags |= NODE_NOPRT;
 		mdoc->next = ROFF_NEXT_CHILD;
 		roff_word_alloc(mdoc, n->child->line, n->child->pos, v);
 		v = mdoc->last->string;
 		v[3] = toupper((unsigned char)v[3]);
 		mdoc->last->flags |= NODE_NOSRC;
 		mdoc->last = n;
 		break;
 	case MDOC_Ox:
 		os = "OpenBSD";
 		break;
 	case MDOC_Ux:
 		os = "UNIX";
 		break;
 	default:
 		abort();
 	}
 	mdoc->next = ROFF_NEXT_CHILD;
 	roff_word_alloc(mdoc, n->line, n->pos, os);
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = n;
 }
 
 static void
 post_it(POST_ARGS)
 {
 	struct roff_node *nbl, *nit, *nch;
 	int		  i, cols;
 	enum mdoc_list	  lt;
 
 	post_prevpar(mdoc);
 
 	nit = mdoc->last;
 	if (nit->type != ROFFT_BLOCK)
 		return;
 
 	nbl = nit->parent->parent;
 	lt = nbl->norm->Bl.type;
 
 	switch (lt) {
 	case LIST_tag:
 	case LIST_hang:
 	case LIST_ohang:
 	case LIST_inset:
 	case LIST_diag:
 		if (nit->head->child == NULL)
 			mandoc_msg(MANDOCERR_IT_NOHEAD,
 			    nit->line, nit->pos, "Bl -%s It",
 			    mdoc_argnames[nbl->args->argv[0].arg]);
 		break;
 	case LIST_bullet:
 	case LIST_dash:
 	case LIST_enum:
 	case LIST_hyphen:
 		if (nit->body == NULL || nit->body->child == NULL)
 			mandoc_msg(MANDOCERR_IT_NOBODY,
 			    nit->line, nit->pos, "Bl -%s It",
 			    mdoc_argnames[nbl->args->argv[0].arg]);
 		/* FALLTHROUGH */
 	case LIST_item:
 		if ((nch = nit->head->child) != NULL)
 			mandoc_msg(MANDOCERR_ARG_SKIP,
 			    nit->line, nit->pos, "It %s",
 			    nch->type == ROFFT_TEXT ? nch->string :
 			    roff_name[nch->tok]);
 		break;
 	case LIST_column:
 		cols = (int)nbl->norm->Bl.ncols;
 
 		assert(nit->head->child == NULL);
 
 		if (nit->head->next->child == NULL &&
 		    nit->head->next->next == NULL) {
 			mandoc_msg(MANDOCERR_MACRO_EMPTY,
 			    nit->line, nit->pos, "It");
 			roff_node_delete(mdoc, nit);
 			break;
 		}
 
 		i = 0;
 		for (nch = nit->child; nch != NULL; nch = nch->next) {
 			if (nch->type != ROFFT_BODY)
 				continue;
 			if (i++ && nch->flags & NODE_LINE)
 				mandoc_msg(MANDOCERR_TA_LINE,
 				    nch->line, nch->pos, "Ta");
 		}
 		if (i < cols || i > cols + 1)
 			mandoc_msg(MANDOCERR_BL_COL, nit->line, nit->pos,
 			    "%d columns, %d cells", cols, i);
 		else if (nit->head->next->child != NULL &&
 		    nit->head->next->child->flags & NODE_LINE)
 			mandoc_msg(MANDOCERR_IT_NOARG,
 			    nit->line, nit->pos, "Bl -column It");
 		break;
 	default:
 		abort();
 	}
 }
 
 static void
 post_bl_block(POST_ARGS)
 {
 	struct roff_node *n, *ni, *nc;
 
 	post_prevpar(mdoc);
 
 	n = mdoc->last;
 	for (ni = n->body->child; ni != NULL; ni = ni->next) {
 		if (ni->body == NULL)
 			continue;
 		nc = ni->body->last;
 		while (nc != NULL) {
 			switch (nc->tok) {
 			case MDOC_Pp:
 			case ROFF_br:
 				break;
 			default:
 				nc = NULL;
 				continue;
 			}
 			if (ni->next == NULL) {
 				mandoc_msg(MANDOCERR_PAR_MOVE, nc->line,
 				    nc->pos, "%s", roff_name[nc->tok]);
 				roff_node_relink(mdoc, nc);
 			} else if (n->norm->Bl.comp == 0 &&
 			    n->norm->Bl.type != LIST_column) {
 				mandoc_msg(MANDOCERR_PAR_SKIP,
 				    nc->line, nc->pos,
 				    "%s before It", roff_name[nc->tok]);
 				roff_node_delete(mdoc, nc);
 			} else
 				break;
 			nc = ni->body->last;
 		}
 	}
 }
 
+/*
+ * If "in" begins with a dot, a word, and whitespace, return a dynamically
+ * allocated copy of "in" that skips all of those.  Otherwise, return NULL.
+ *
+ * This is a partial workaround for the TODO list item beginning with:
+ * - When the -width string contains macros, the macros must be rendered
+ */
+static char *
+skip_leading_dot_word(const char *in)
+{
+	const char *iter = in;
+	const char *space;
+
+	if (*iter != '.')
+		return NULL;
+	iter++;
+
+	while (*iter != '\0' && !isspace(*iter))
+		iter++;
+	/*
+	 * If the dot was followed by space or NUL,
+	 * do not skip anything.
+	 */
+	if (iter == in + 1)
+		return NULL;
+
+	space = iter;
+	while (isspace(*iter))
+		iter++;
+	/*
+	 * If the word was not followed by space,
+	 * do not skip anything.
+	 */
+	if (iter == space)
+		return NULL;
+
+	return strdup(iter);
+}
+
 /*
  * If the argument of -offset or -width is a macro,
  * replace it with the associated default width.
  */
 static void
 rewrite_macro2len(struct roff_man *mdoc, char **arg)
 {
 	size_t		  width;
 	enum roff_tok	  tok;
+	char		 *newarg;
 
+	newarg = NULL;
 	if (*arg == NULL)
 		return;
 	else if ( ! strcmp(*arg, "Ds"))
 		width = 6;
-	else if ((tok = roffhash_find(mdoc->mdocmac, *arg, 0)) == TOKEN_NONE)
-		return;
-	else
+	else if ((tok = roffhash_find(mdoc->mdocmac, *arg, 0)) != TOKEN_NONE)
 		width = macro2len(tok);
+	else if ((newarg = skip_leading_dot_word(*arg)) == NULL)
+		return;
 
 	free(*arg);
-	mandoc_asprintf(arg, "%zun", width);
+	if (newarg != NULL)
+		*arg = newarg;
+	else
+		mandoc_asprintf(arg, "%zun", width);
 }
 
 static void
 post_bl_head(POST_ARGS)
 {
 	struct roff_node *nbl, *nh, *nch, *nnext;
 	struct mdoc_argv *argv;
 	int		  i, j;
 
 	post_bl_norm(mdoc);
 
 	nh = mdoc->last;
 	if (nh->norm->Bl.type != LIST_column) {
 		if ((nch = nh->child) == NULL)
 			return;
 		mandoc_msg(MANDOCERR_ARG_EXCESS,
 		    nch->line, nch->pos, "Bl ... %s", nch->string);
 		while (nch != NULL) {
 			roff_node_delete(mdoc, nch);
 			nch = nh->child;
 		}
 		return;
 	}
 
 	/*
 	 * Append old-style lists, where the column width specifiers
 	 * trail as macro parameters, to the new-style ("normal-form")
 	 * lists where they're argument values following -column.
 	 */
 
 	if (nh->child == NULL)
 		return;
 
 	nbl = nh->parent;
 	for (j = 0; j < (int)nbl->args->argc; j++)
 		if (nbl->args->argv[j].arg == MDOC_Column)
 			break;
 
 	assert(j < (int)nbl->args->argc);
 
 	/*
 	 * Accommodate for new-style groff column syntax.  Shuffle the
 	 * child nodes, all of which must be TEXT, as arguments for the
 	 * column field.  Then, delete the head children.
 	 */
 
 	argv = nbl->args->argv + j;
 	i = argv->sz;
 	for (nch = nh->child; nch != NULL; nch = nch->next)
 		argv->sz++;
 	argv->value = mandoc_reallocarray(argv->value,
 	    argv->sz, sizeof(char *));
 
 	nh->norm->Bl.ncols = argv->sz;
 	nh->norm->Bl.cols = (void *)argv->value;
 
 	for (nch = nh->child; nch != NULL; nch = nnext) {
 		argv->value[i++] = nch->string;
 		nch->string = NULL;
 		nnext = nch->next;
 		roff_node_delete(NULL, nch);
 	}
 	nh->child = NULL;
 }
 
 static void
 post_bl(POST_ARGS)
 {
 	struct roff_node	*nbody;           /* of the Bl */
 	struct roff_node	*nchild, *nnext;  /* of the Bl body */
 	const char		*prev_Er;
 	int			 order;
 
 	nbody = mdoc->last;
 	switch (nbody->type) {
 	case ROFFT_BLOCK:
 		post_bl_block(mdoc);
 		return;
 	case ROFFT_HEAD:
 		post_bl_head(mdoc);
 		return;
 	case ROFFT_BODY:
 		break;
 	default:
 		return;
 	}
 	if (nbody->end != ENDBODY_NOT)
 		return;
 
 	/*
 	 * Up to the first item, move nodes before the list,
 	 * but leave transparent nodes where they are
 	 * if they precede an item.
 	 * The next non-transparent node is kept in nchild.
 	 * It only needs to be updated after a non-transparent
 	 * node was moved out, and at the very beginning
 	 * when no node at all was moved yet.
 	 */
 
 	nchild = mdoc->last;
 	for (;;) {
 		if (nchild == mdoc->last)
 			nchild = roff_node_child(nbody);
 		if (nchild == NULL) {
 			mdoc->last = nbody;
 			mandoc_msg(MANDOCERR_BLK_EMPTY,
 			    nbody->line, nbody->pos, "Bl");
 			return;
 		}
 		if (nchild->tok == MDOC_It) {
 			mdoc->last = nbody;
 			break;
 		}
 		mandoc_msg(MANDOCERR_BL_MOVE, nbody->child->line,
 		    nbody->child->pos, "%s", roff_name[nbody->child->tok]);
 		if (nbody->parent->prev == NULL) {
 			mdoc->last = nbody->parent->parent;
 			mdoc->next = ROFF_NEXT_CHILD;
 		} else {
 			mdoc->last = nbody->parent->prev;
 			mdoc->next = ROFF_NEXT_SIBLING;
 		}
 		roff_node_relink(mdoc, nbody->child);
 	}
 
 	/*
 	 * We have reached the first item,
 	 * so moving nodes out is no longer possible.
 	 * But in .Bl -column, the first rows may be implicit,
 	 * that is, they may not start with .It macros.
 	 * Such rows may be followed by nodes generated on the
 	 * roff level, for example .TS.
 	 * Wrap such roff nodes into an implicit row.
 	 */
 
 	while (nchild != NULL) {
 		if (nchild->tok == MDOC_It) {
 			nchild = roff_node_next(nchild);
 			continue;
 		}
 		nnext = nchild->next;
 		mdoc->last = nchild->prev;
 		mdoc->next = ROFF_NEXT_SIBLING;
 		roff_block_alloc(mdoc, nchild->line, nchild->pos, MDOC_It);
 		roff_head_alloc(mdoc, nchild->line, nchild->pos, MDOC_It);
 		mdoc->next = ROFF_NEXT_SIBLING;
 		roff_body_alloc(mdoc, nchild->line, nchild->pos, MDOC_It);
 		while (nchild->tok != MDOC_It) {
 			roff_node_relink(mdoc, nchild);
 			if (nnext == NULL)
 				break;
 			nchild = nnext;
 			nnext = nchild->next;
 			mdoc->next = ROFF_NEXT_SIBLING;
 		}
 		mdoc->last = nbody;
 	}
 
 	if (mdoc->meta.os_e != MANDOC_OS_NETBSD)
 		return;
 
 	prev_Er = NULL;
 	for (nchild = nbody->child; nchild != NULL; nchild = nchild->next) {
 		if (nchild->tok != MDOC_It)
 			continue;
 		if ((nnext = nchild->head->child) == NULL)
 			continue;
 		if (nnext->type == ROFFT_BLOCK)
 			nnext = nnext->body->child;
 		if (nnext == NULL || nnext->tok != MDOC_Er)
 			continue;
 		nnext = nnext->child;
 		if (prev_Er != NULL) {
 			order = strcmp(prev_Er, nnext->string);
 			if (order > 0)
 				mandoc_msg(MANDOCERR_ER_ORDER,
 				    nnext->line, nnext->pos,
 				    "Er %s %s (NetBSD)",
 				    prev_Er, nnext->string);
 			else if (order == 0)
 				mandoc_msg(MANDOCERR_ER_REP,
 				    nnext->line, nnext->pos,
 				    "Er %s (NetBSD)", prev_Er);
 		}
 		prev_Er = nnext->string;
 	}
 }
 
 static void
 post_bk(POST_ARGS)
 {
 	struct roff_node	*n;
 
 	n = mdoc->last;
 
 	if (n->type == ROFFT_BLOCK && n->body->child == NULL) {
 		mandoc_msg(MANDOCERR_BLK_EMPTY, n->line, n->pos, "Bk");
 		roff_node_delete(mdoc, n);
 	}
 }
 
 static void
 post_sm(POST_ARGS)
 {
 	struct roff_node	*nch;
 
 	nch = mdoc->last->child;
 
 	if (nch == NULL) {
 		mdoc->flags ^= MDOC_SMOFF;
 		return;
 	}
 
 	assert(nch->type == ROFFT_TEXT);
 
 	if ( ! strcmp(nch->string, "on")) {
 		mdoc->flags &= ~MDOC_SMOFF;
 		return;
 	}
 	if ( ! strcmp(nch->string, "off")) {
 		mdoc->flags |= MDOC_SMOFF;
 		return;
 	}
 
 	mandoc_msg(MANDOCERR_SM_BAD, nch->line, nch->pos,
 	    "%s %s", roff_name[mdoc->last->tok], nch->string);
 	roff_node_relink(mdoc, nch);
 	return;
 }
 
 static void
 post_root(POST_ARGS)
 {
 	struct roff_node *n;
 
 	/* Add missing prologue data. */
 
 	if (mdoc->meta.date == NULL)
 		mdoc->meta.date = mandoc_normdate(NULL, NULL);
 
 	if (mdoc->meta.title == NULL) {
 		mandoc_msg(MANDOCERR_DT_NOTITLE, 0, 0, "EOF");
 		mdoc->meta.title = mandoc_strdup("UNTITLED");
 	}
 
 	if (mdoc->meta.vol == NULL)
 		mdoc->meta.vol = mandoc_strdup("LOCAL");
 
 	if (mdoc->meta.os == NULL) {
 		mandoc_msg(MANDOCERR_OS_MISSING, 0, 0, NULL);
 		mdoc->meta.os = mandoc_strdup("");
 	} else if (mdoc->meta.os_e &&
 	    (mdoc->meta.rcsids & (1 << mdoc->meta.os_e)) == 0)
 		mandoc_msg(MANDOCERR_RCS_MISSING, 0, 0,
 		    mdoc->meta.os_e == MANDOC_OS_OPENBSD ?
 		    "(OpenBSD)" : "(NetBSD)");
 
 	if (mdoc->meta.arch != NULL &&
 	    arch_valid(mdoc->meta.arch, mdoc->meta.os_e) == 0) {
 		n = mdoc->meta.first->child;
 		while (n->tok != MDOC_Dt ||
 		    n->child == NULL ||
 		    n->child->next == NULL ||
 		    n->child->next->next == NULL)
 			n = n->next;
 		n = n->child->next->next;
 		mandoc_msg(MANDOCERR_ARCH_BAD, n->line, n->pos,
 		    "Dt ... %s %s", mdoc->meta.arch,
 		    mdoc->meta.os_e == MANDOC_OS_OPENBSD ?
 		    "(OpenBSD)" : "(NetBSD)");
 	}
 
 	/* Check that we begin with a proper `Sh'. */
 
 	n = mdoc->meta.first->child;
 	while (n != NULL &&
 	    (n->type == ROFFT_COMMENT ||
 	     (n->tok >= MDOC_Dd &&
 	      mdoc_macro(n->tok)->flags & MDOC_PROLOGUE)))
 		n = n->next;
 
 	if (n == NULL)
 		mandoc_msg(MANDOCERR_DOC_EMPTY, 0, 0, NULL);
 	else if (n->tok != MDOC_Sh)
 		mandoc_msg(MANDOCERR_SEC_BEFORE, n->line, n->pos,
 		    "%s", roff_name[n->tok]);
 }
 
 static void
 post_rs(POST_ARGS)
 {
 	struct roff_node *np, *nch, *next, *prev;
 	int		  i, j;
 
 	np = mdoc->last;
 
 	if (np->type != ROFFT_BODY)
 		return;
 
 	if (np->child == NULL) {
 		mandoc_msg(MANDOCERR_RS_EMPTY, np->line, np->pos, "Rs");
 		return;
 	}
 
 	/*
 	 * The full `Rs' block needs special handling to order the
 	 * sub-elements according to `rsord'.  Pick through each element
 	 * and correctly order it.  This is an insertion sort.
 	 */
 
 	next = NULL;
 	for (nch = np->child->next; nch != NULL; nch = next) {
 		/* Determine order number of this child. */
 		for (i = 0; i < RSORD_MAX; i++)
 			if (rsord[i] == nch->tok)
 				break;
 
 		if (i == RSORD_MAX) {
 			mandoc_msg(MANDOCERR_RS_BAD, nch->line, nch->pos,
 			    "%s", roff_name[nch->tok]);
 			i = -1;
 		} else if (nch->tok == MDOC__J || nch->tok == MDOC__B)
 			np->norm->Rs.quote_T++;
 
 		/*
 		 * Remove this child from the chain.  This somewhat
 		 * repeats roff_node_unlink(), but since we're
 		 * just re-ordering, there's no need for the
 		 * full unlink process.
 		 */
 
 		if ((next = nch->next) != NULL)
 			next->prev = nch->prev;
 
 		if ((prev = nch->prev) != NULL)
 			prev->next = nch->next;
 
 		nch->prev = nch->next = NULL;
 
 		/*
 		 * Scan back until we reach a node that's
 		 * to be ordered before this child.
 		 */
 
 		for ( ; prev ; prev = prev->prev) {
 			/* Determine order of `prev'. */
 			for (j = 0; j < RSORD_MAX; j++)
 				if (rsord[j] == prev->tok)
 					break;
 			if (j == RSORD_MAX)
 				j = -1;
 
 			if (j <= i)
 				break;
 		}
 
 		/*
 		 * Set this child back into its correct place
 		 * in front of the `prev' node.
 		 */
 
 		nch->prev = prev;
 
 		if (prev == NULL) {
 			np->child->prev = nch;
 			nch->next = np->child;
 			np->child = nch;
 		} else {
 			if (prev->next)
 				prev->next->prev = nch;
 			nch->next = prev->next;
 			prev->next = nch;
 		}
 	}
 }
 
 /*
  * For some arguments of some macros,
  * convert all breakable hyphens into ASCII_HYPH.
  */
 static void
 post_hyph(POST_ARGS)
 {
 	struct roff_node	*n, *nch;
 	char			*cp;
 
 	n = mdoc->last;
 	for (nch = n->child; nch != NULL; nch = nch->next) {
 		if (nch->type != ROFFT_TEXT)
 			continue;
 		cp = nch->string;
 		if (*cp == '\0')
 			continue;
 		while (*(++cp) != '\0')
 			if (*cp == '-' &&
 			    isalpha((unsigned char)cp[-1]) &&
 			    isalpha((unsigned char)cp[1])) {
 				if (n->tag == NULL && n->flags & NODE_ID)
 					n->tag = mandoc_strdup(nch->string);
 				*cp = ASCII_HYPH;
 			}
 	}
 }
 
 static void
 post_ns(POST_ARGS)
 {
 	struct roff_node	*n;
 
 	n = mdoc->last;
 	if (n->flags & NODE_LINE ||
 	    (n->next != NULL && n->next->flags & NODE_DELIMC))
 		mandoc_msg(MANDOCERR_NS_SKIP, n->line, n->pos, NULL);
 }
 
 static void
 post_sx(POST_ARGS)
 {
 	post_delim(mdoc);
 	post_hyph(mdoc);
 }
 
 static void
 post_sh(POST_ARGS)
 {
 	post_section(mdoc);
 
 	switch (mdoc->last->type) {
 	case ROFFT_HEAD:
 		post_sh_head(mdoc);
 		break;
 	case ROFFT_BODY:
 		switch (mdoc->lastsec)  {
 		case SEC_NAME:
 			post_sh_name(mdoc);
 			break;
 		case SEC_SEE_ALSO:
 			post_sh_see_also(mdoc);
 			break;
 		case SEC_AUTHORS:
 			post_sh_authors(mdoc);
 			break;
 		default:
 			break;
 		}
 		break;
 	default:
 		break;
 	}
 }
 
 static void
 post_sh_name(POST_ARGS)
 {
 	struct roff_node *n;
 	int hasnm, hasnd;
 
 	hasnm = hasnd = 0;
 
 	for (n = mdoc->last->child; n != NULL; n = n->next) {
 		switch (n->tok) {
 		case MDOC_Nm:
 			if (hasnm && n->child != NULL)
 				mandoc_msg(MANDOCERR_NAMESEC_PUNCT,
 				    n->line, n->pos,
 				    "Nm %s", n->child->string);
 			hasnm = 1;
 			continue;
 		case MDOC_Nd:
 			hasnd = 1;
 			if (n->next != NULL)
 				mandoc_msg(MANDOCERR_NAMESEC_ND,
 				    n->line, n->pos, NULL);
 			break;
 		case TOKEN_NONE:
 			if (n->type == ROFFT_TEXT &&
 			    n->string[0] == ',' && n->string[1] == '\0' &&
 			    n->next != NULL && n->next->tok == MDOC_Nm) {
 				n = n->next;
 				continue;
 			}
 			/* FALLTHROUGH */
 		default:
 			mandoc_msg(MANDOCERR_NAMESEC_BAD,
 			    n->line, n->pos, "%s", roff_name[n->tok]);
 			continue;
 		}
 		break;
 	}
 
 	if ( ! hasnm)
 		mandoc_msg(MANDOCERR_NAMESEC_NONM,
 		    mdoc->last->line, mdoc->last->pos, NULL);
 	if ( ! hasnd)
 		mandoc_msg(MANDOCERR_NAMESEC_NOND,
 		    mdoc->last->line, mdoc->last->pos, NULL);
 }
 
 static void
 post_sh_see_also(POST_ARGS)
 {
 	const struct roff_node	*n;
 	const char		*name, *sec;
 	const char		*lastname, *lastsec, *lastpunct;
 	int			 cmp;
 
 	n = mdoc->last->child;
 	lastname = lastsec = lastpunct = NULL;
 	while (n != NULL) {
 		if (n->tok != MDOC_Xr ||
 		    n->child == NULL ||
 		    n->child->next == NULL)
 			break;
 
 		/* Process one .Xr node. */
 
 		name = n->child->string;
 		sec = n->child->next->string;
 		if (lastsec != NULL) {
 			if (lastpunct[0] != ',' || lastpunct[1] != '\0')
 				mandoc_msg(MANDOCERR_XR_PUNCT, n->line,
 				    n->pos, "%s before %s(%s)",
 				    lastpunct, name, sec);
 			cmp = strcmp(lastsec, sec);
 			if (cmp > 0)
 				mandoc_msg(MANDOCERR_XR_ORDER, n->line,
 				    n->pos, "%s(%s) after %s(%s)",
 				    name, sec, lastname, lastsec);
 			else if (cmp == 0 &&
 			    strcasecmp(lastname, name) > 0)
 				mandoc_msg(MANDOCERR_XR_ORDER, n->line,
 				    n->pos, "%s after %s", name, lastname);
 		}
 		lastname = name;
 		lastsec = sec;
 
 		/* Process the following node. */
 
 		n = n->next;
 		if (n == NULL)
 			break;
 		if (n->tok == MDOC_Xr) {
 			lastpunct = "none";
 			continue;
 		}
 		if (n->type != ROFFT_TEXT)
 			break;
 		for (name = n->string; *name != '\0'; name++)
 			if (isalpha((const unsigned char)*name))
 				return;
 		lastpunct = n->string;
 		if (n->next == NULL || n->next->tok == MDOC_Rs)
 			mandoc_msg(MANDOCERR_XR_PUNCT, n->line,
 			    n->pos, "%s after %s(%s)",
 			    lastpunct, lastname, lastsec);
 		n = n->next;
 	}
 }
 
 static int
 child_an(const struct roff_node *n)
 {
 
 	for (n = n->child; n != NULL; n = n->next)
 		if ((n->tok == MDOC_An && n->child != NULL) || child_an(n))
 			return 1;
 	return 0;
 }
 
 static void
 post_sh_authors(POST_ARGS)
 {
 
 	if ( ! child_an(mdoc->last))
 		mandoc_msg(MANDOCERR_AN_MISSING,
 		    mdoc->last->line, mdoc->last->pos, NULL);
 }
 
 /*
  * Return an upper bound for the string distance (allowing
  * transpositions).  Not a full Levenshtein implementation
  * because Levenshtein is quadratic in the string length
  * and this function is called for every standard name,
  * so the check for each custom name would be cubic.
  * The following crude heuristics is linear, resulting
  * in quadratic behaviour for checking one custom name,
  * which does not cause measurable slowdown.
  */
 static int
 similar(const char *s1, const char *s2)
 {
 	const int	maxdist = 3;
 	int		dist = 0;
 
 	while (s1[0] != '\0' && s2[0] != '\0') {
 		if (s1[0] == s2[0]) {
 			s1++;
 			s2++;
 			continue;
 		}
 		if (++dist > maxdist)
 			return INT_MAX;
 		if (s1[1] == s2[1]) {  /* replacement */
 			s1++;
 			s2++;
 		} else if (s1[0] == s2[1] && s1[1] == s2[0]) {
 			s1 += 2;	/* transposition */
 			s2 += 2;
 		} else if (s1[0] == s2[1])  /* insertion */
 			s2++;
 		else if (s1[1] == s2[0])  /* deletion */
 			s1++;
 		else
 			return INT_MAX;
 	}
 	dist += strlen(s1) + strlen(s2);
 	return dist > maxdist ? INT_MAX : dist;
 }
 
 static void
 post_sh_head(POST_ARGS)
 {
 	struct roff_node	*nch;
 	const char		*goodsec;
 	const char *const	*testsec;
 	int			 dist, mindist;
 	enum roff_sec		 sec;
 
 	/*
 	 * Process a new section.  Sections are either "named" or
 	 * "custom".  Custom sections are user-defined, while named ones
 	 * follow a conventional order and may only appear in certain
 	 * manual sections.
 	 */
 
 	sec = mdoc->last->sec;
 
 	/* The NAME should be first. */
 
 	if (sec != SEC_NAME && mdoc->lastnamed == SEC_NONE)
 		mandoc_msg(MANDOCERR_NAMESEC_FIRST,
 		    mdoc->last->line, mdoc->last->pos, "Sh %s",
 		    sec != SEC_CUSTOM ? secnames[sec] :
 		    (nch = mdoc->last->child) == NULL ? "" :
 		    nch->type == ROFFT_TEXT ? nch->string :
 		    roff_name[nch->tok]);
 
 	/* The SYNOPSIS gets special attention in other areas. */
 
 	if (sec == SEC_SYNOPSIS) {
 		roff_setreg(mdoc->roff, "nS", 1, '=');
 		mdoc->flags |= MDOC_SYNOPSIS;
 	} else {
 		roff_setreg(mdoc->roff, "nS", 0, '=');
 		mdoc->flags &= ~MDOC_SYNOPSIS;
 	}
 	if (sec == SEC_DESCRIPTION)
 		fn_prio = TAG_STRONG;
 
 	/* Mark our last section. */
 
 	mdoc->lastsec = sec;
 
 	/* We don't care about custom sections after this. */
 
 	if (sec == SEC_CUSTOM) {
 		if ((nch = mdoc->last->child) == NULL ||
 		    nch->type != ROFFT_TEXT || nch->next != NULL)
 			return;
 		goodsec = NULL;
 		mindist = INT_MAX;
 		for (testsec = secnames + 1; *testsec != NULL; testsec++) {
 			dist = similar(nch->string, *testsec);
 			if (dist < mindist) {
 				goodsec = *testsec;
 				mindist = dist;
 			}
 		}
 		if (goodsec != NULL)
 			mandoc_msg(MANDOCERR_SEC_TYPO, nch->line, nch->pos,
 			    "Sh %s instead of %s", nch->string, goodsec);
 		return;
 	}
 
 	/*
 	 * Check whether our non-custom section is being repeated or is
 	 * out of order.
 	 */
 
 	if (sec == mdoc->lastnamed)
 		mandoc_msg(MANDOCERR_SEC_REP, mdoc->last->line,
 		    mdoc->last->pos, "Sh %s", secnames[sec]);
 
 	if (sec < mdoc->lastnamed)
 		mandoc_msg(MANDOCERR_SEC_ORDER, mdoc->last->line,
 		    mdoc->last->pos, "Sh %s", secnames[sec]);
 
 	/* Mark the last named section. */
 
 	mdoc->lastnamed = sec;
 
 	/* Check particular section/manual conventions. */
 
 	if (mdoc->meta.msec == NULL)
 		return;
 
 	goodsec = NULL;
 	switch (sec) {
 	case SEC_ERRORS:
 		if (*mdoc->meta.msec == '4')
 			break;
 		goodsec = "2, 3, 4, 9";
 		/* FALLTHROUGH */
 	case SEC_RETURN_VALUES:
 	case SEC_LIBRARY:
 		if (*mdoc->meta.msec == '2')
 			break;
 		if (*mdoc->meta.msec == '3')
 			break;
 		if (NULL == goodsec)
 			goodsec = "2, 3, 9";
 		/* FALLTHROUGH */
 	case SEC_CONTEXT:
 		if (*mdoc->meta.msec == '9')
 			break;
 		if (NULL == goodsec)
 			goodsec = "9";
 		mandoc_msg(MANDOCERR_SEC_MSEC,
 		    mdoc->last->line, mdoc->last->pos,
 		    "Sh %s for %s only", secnames[sec], goodsec);
 		break;
 	default:
 		break;
 	}
 }
 
 static void
 post_xr(POST_ARGS)
 {
 	struct roff_node *n, *nch;
 
 	n = mdoc->last;
 	nch = n->child;
 	if (nch->next == NULL) {
 		mandoc_msg(MANDOCERR_XR_NOSEC,
 		    n->line, n->pos, "Xr %s", nch->string);
 	} else {
 		assert(nch->next == n->last);
 		if(mandoc_xr_add(nch->next->string, nch->string,
 		    nch->line, nch->pos))
 			mandoc_msg(MANDOCERR_XR_SELF,
 			    nch->line, nch->pos, "Xr %s %s",
 			    nch->string, nch->next->string);
 	}
 	post_delim_nb(mdoc);
 }
 
 static void
 post_section(POST_ARGS)
 {
 	struct roff_node *n, *nch;
 	char		 *cp, *tag;
 
 	n = mdoc->last;
 	switch (n->type) {
 	case ROFFT_BLOCK:
 		post_prevpar(mdoc);
 		return;
 	case ROFFT_HEAD:
 		tag = NULL;
 		deroff(&tag, n);
 		if (tag != NULL) {
 			for (cp = tag; *cp != '\0'; cp++)
 				if (*cp == ' ')
 					*cp = '_';
 			if ((nch = n->child) != NULL &&
 			    nch->type == ROFFT_TEXT &&
 			    strcmp(nch->string, tag) == 0)
 				tag_put(NULL, TAG_STRONG, n);
 			else
 				tag_put(tag, TAG_FALLBACK, n);
 			free(tag);
 		}
 		post_delim(mdoc);
 		post_hyph(mdoc);
 		return;
 	case ROFFT_BODY:
 		break;
 	default:
 		return;
 	}
 	if ((nch = n->child) != NULL &&
 	    (nch->tok == MDOC_Pp || nch->tok == ROFF_br ||
 	     nch->tok == ROFF_sp)) {
 		mandoc_msg(MANDOCERR_PAR_SKIP, nch->line, nch->pos,
 		    "%s after %s", roff_name[nch->tok],
 		    roff_name[n->tok]);
 		roff_node_delete(mdoc, nch);
 	}
 	if ((nch = n->last) != NULL &&
 	    (nch->tok == MDOC_Pp || nch->tok == ROFF_br)) {
 		mandoc_msg(MANDOCERR_PAR_SKIP, nch->line, nch->pos,
 		    "%s at the end of %s", roff_name[nch->tok],
 		    roff_name[n->tok]);
 		roff_node_delete(mdoc, nch);
 	}
 }
 
 static void
 post_prevpar(POST_ARGS)
 {
 	struct roff_node *n, *np;
 
 	n = mdoc->last;
 	if (n->type != ROFFT_ELEM && n->type != ROFFT_BLOCK)
 		return;
 	if ((np = roff_node_prev(n)) == NULL)
 		return;
 
 	/*
 	 * Don't allow `Pp' prior to a paragraph-type
 	 * block: `Pp' or non-compact `Bd' or `Bl'.
 	 */
 
 	if (np->tok != MDOC_Pp && np->tok != ROFF_br)
 		return;
 	if (n->tok == MDOC_Bl && n->norm->Bl.comp)
 		return;
 	if (n->tok == MDOC_Bd && n->norm->Bd.comp)
 		return;
 	if (n->tok == MDOC_It && n->parent->norm->Bl.comp)
 		return;
 
 	mandoc_msg(MANDOCERR_PAR_SKIP, np->line, np->pos,
 	    "%s before %s", roff_name[np->tok], roff_name[n->tok]);
 	roff_node_delete(mdoc, np);
 }
 
 static void
 post_par(POST_ARGS)
 {
 	struct roff_node *np;
 
 	fn_prio = TAG_STRONG;
 	post_prevpar(mdoc);
 
 	np = mdoc->last;
 	if (np->child != NULL)
 		mandoc_msg(MANDOCERR_ARG_SKIP, np->line, np->pos,
 		    "%s %s", roff_name[np->tok], np->child->string);
 }
 
 static void
 post_dd(POST_ARGS)
 {
 	struct roff_node *n;
 
 	n = mdoc->last;
 	n->flags |= NODE_NOPRT;
 
 	if (mdoc->meta.date != NULL) {
 		mandoc_msg(MANDOCERR_PROLOG_REP, n->line, n->pos, "Dd");
 		free(mdoc->meta.date);
 	} else if (mdoc->flags & MDOC_PBODY)
 		mandoc_msg(MANDOCERR_PROLOG_LATE, n->line, n->pos, "Dd");
 	else if (mdoc->meta.title != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_ORDER,
 		    n->line, n->pos, "Dd after Dt");
 	else if (mdoc->meta.os != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_ORDER,
 		    n->line, n->pos, "Dd after Os");
 
 	if (mdoc->quick && n != NULL)
 		mdoc->meta.date = mandoc_strdup("");
 	else
 		mdoc->meta.date = mandoc_normdate(n->child, n);
 }
 
 static void
 post_dt(POST_ARGS)
 {
 	struct roff_node *nn, *n;
 	const char	 *cp;
 	char		 *p;
 
 	n = mdoc->last;
 	n->flags |= NODE_NOPRT;
 
 	if (mdoc->flags & MDOC_PBODY) {
 		mandoc_msg(MANDOCERR_DT_LATE, n->line, n->pos, "Dt");
 		return;
 	}
 
 	if (mdoc->meta.title != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_REP, n->line, n->pos, "Dt");
 	else if (mdoc->meta.os != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_ORDER,
 		    n->line, n->pos, "Dt after Os");
 
 	free(mdoc->meta.title);
 	free(mdoc->meta.msec);
 	free(mdoc->meta.vol);
 	free(mdoc->meta.arch);
 
 	mdoc->meta.title = NULL;
 	mdoc->meta.msec = NULL;
 	mdoc->meta.vol = NULL;
 	mdoc->meta.arch = NULL;
 
 	/* Mandatory first argument: title. */
 
 	nn = n->child;
 	if (nn == NULL || *nn->string == '\0') {
 		mandoc_msg(MANDOCERR_DT_NOTITLE, n->line, n->pos, "Dt");
 		mdoc->meta.title = mandoc_strdup("UNTITLED");
 	} else {
 		mdoc->meta.title = mandoc_strdup(nn->string);
 
 		/* Check that all characters are uppercase. */
 
 		for (p = nn->string; *p != '\0'; p++)
 			if (islower((unsigned char)*p)) {
 				mandoc_msg(MANDOCERR_TITLE_CASE, nn->line,
 				    nn->pos + (int)(p - nn->string),
 				    "Dt %s", nn->string);
 				break;
 			}
 	}
 
 	/* Mandatory second argument: section. */
 
 	if (nn != NULL)
 		nn = nn->next;
 
 	if (nn == NULL) {
 		mandoc_msg(MANDOCERR_MSEC_MISSING, n->line, n->pos,
 		    "Dt %s", mdoc->meta.title);
 		mdoc->meta.vol = mandoc_strdup("LOCAL");
 		return;  /* msec and arch remain NULL. */
 	}
 
 	mdoc->meta.msec = mandoc_strdup(nn->string);
 
 	/* Infer volume title from section number. */
 
 	cp = mandoc_a2msec(nn->string);
 	if (cp == NULL) {
 		mandoc_msg(MANDOCERR_MSEC_BAD,
 		    nn->line, nn->pos, "Dt ... %s", nn->string);
 		mdoc->meta.vol = mandoc_strdup(nn->string);
 	} else {
 		mdoc->meta.vol = mandoc_strdup(cp);
 		if (mdoc->filesec != '\0' &&
 		    mdoc->filesec != *nn->string &&
 		    *nn->string >= '1' && *nn->string <= '9')
 			mandoc_msg(MANDOCERR_MSEC_FILE, nn->line, nn->pos,
 			    "*.%c vs Dt ... %c", mdoc->filesec, *nn->string);
 	}
 
 	/* Optional third argument: architecture. */
 
 	if ((nn = nn->next) == NULL)
 		return;
 
 	for (p = nn->string; *p != '\0'; p++)
 		*p = tolower((unsigned char)*p);
 	mdoc->meta.arch = mandoc_strdup(nn->string);
 
 	/* Ignore fourth and later arguments. */
 
 	if ((nn = nn->next) != NULL)
 		mandoc_msg(MANDOCERR_ARG_EXCESS,
 		    nn->line, nn->pos, "Dt ... %s", nn->string);
 }
 
 static void
 post_bx(POST_ARGS)
 {
 	struct roff_node	*n, *nch;
 	const char		*macro;
 
 	post_delim_nb(mdoc);
 
 	n = mdoc->last;
 	nch = n->child;
 
 	if (nch != NULL) {
 		macro = !strcmp(nch->string, "Open") ? "Ox" :
 		    !strcmp(nch->string, "Net") ? "Nx" :
 		    !strcmp(nch->string, "Free") ? "Fx" :
 		    !strcmp(nch->string, "DragonFly") ? "Dx" : NULL;
 		if (macro != NULL)
 			mandoc_msg(MANDOCERR_BX,
 			    n->line, n->pos, "%s", macro);
 		mdoc->last = nch;
 		nch = nch->next;
 		mdoc->next = ROFF_NEXT_SIBLING;
 		roff_elem_alloc(mdoc, n->line, n->pos, MDOC_Ns);
 		mdoc->last->flags |= NODE_NOSRC;
 		mdoc->next = ROFF_NEXT_SIBLING;
 	} else
 		mdoc->next = ROFF_NEXT_CHILD;
 	roff_word_alloc(mdoc, n->line, n->pos, "BSD");
 	mdoc->last->flags |= NODE_NOSRC;
 
 	if (nch == NULL) {
 		mdoc->last = n;
 		return;
 	}
 
 	roff_elem_alloc(mdoc, n->line, n->pos, MDOC_Ns);
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->next = ROFF_NEXT_SIBLING;
 	roff_word_alloc(mdoc, n->line, n->pos, "-");
 	mdoc->last->flags |= NODE_NOSRC;
 	roff_elem_alloc(mdoc, n->line, n->pos, MDOC_Ns);
 	mdoc->last->flags |= NODE_NOSRC;
 	mdoc->last = n;
 
 	/*
 	 * Make `Bx's second argument always start with an uppercase
 	 * letter.  Groff checks if it's an "accepted" term, but we just
 	 * uppercase blindly.
 	 */
 
 	*nch->string = (char)toupper((unsigned char)*nch->string);
 }
 
 static void
 post_os(POST_ARGS)
 {
 #ifndef OSNAME
 	struct utsname	  utsname;
 	static char	 *defbuf;
 #endif
 	struct roff_node *n;
 
 	n = mdoc->last;
 	n->flags |= NODE_NOPRT;
 
 	if (mdoc->meta.os != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_REP, n->line, n->pos, "Os");
 	else if (mdoc->flags & MDOC_PBODY)
 		mandoc_msg(MANDOCERR_PROLOG_LATE, n->line, n->pos, "Os");
 
 	post_delim(mdoc);
 
 	/*
 	 * Set the operating system by way of the `Os' macro.
 	 * The order of precedence is:
 	 * 1. the argument of the `Os' macro, unless empty
 	 * 2. the -Ios=foo command line argument, if provided
 	 * 3. -DOSNAME="\"foo\"", if provided during compilation
 	 * 4. "sysname release" from uname(3)
 	 */
 
 	free(mdoc->meta.os);
 	mdoc->meta.os = NULL;
 	deroff(&mdoc->meta.os, n);
 	if (mdoc->meta.os)
 		goto out;
 
 	if (mdoc->os_s != NULL) {
 		mdoc->meta.os = mandoc_strdup(mdoc->os_s);
 		goto out;
 	}
 
 #ifdef OSNAME
 	mdoc->meta.os = mandoc_strdup(OSNAME);
 #else /*!OSNAME */
 	if (defbuf == NULL) {
 		if (uname(&utsname) == -1) {
 			mandoc_msg(MANDOCERR_OS_UNAME, n->line, n->pos, "Os");
 			defbuf = mandoc_strdup("UNKNOWN");
 		} else
 			mandoc_asprintf(&defbuf, "%s %s",
 			    utsname.sysname, utsname.release);
 	}
 	mdoc->meta.os = mandoc_strdup(defbuf);
 #endif /*!OSNAME*/
 
 out:
 	if (mdoc->meta.os_e == MANDOC_OS_OTHER) {
 		if (strstr(mdoc->meta.os, "OpenBSD") != NULL)
 			mdoc->meta.os_e = MANDOC_OS_OPENBSD;
 		else if (strstr(mdoc->meta.os, "NetBSD") != NULL)
 			mdoc->meta.os_e = MANDOC_OS_NETBSD;
 	}
 
 	/*
 	 * This is the earliest point where we can check
 	 * Mdocdate conventions because we don't know
 	 * the operating system earlier.
 	 */
 
 	if (n->child != NULL)
 		mandoc_msg(MANDOCERR_OS_ARG, n->child->line, n->child->pos,
 		    "Os %s (%s)", n->child->string,
 		    mdoc->meta.os_e == MANDOC_OS_OPENBSD ?
 		    "OpenBSD" : "NetBSD");
 
 	while (n->tok != MDOC_Dd)
 		if ((n = n->prev) == NULL)
 			return;
 	if ((n = n->child) == NULL)
 		return;
 	if (strncmp(n->string, "$" "Mdocdate", 9)) {
 		if (mdoc->meta.os_e == MANDOC_OS_OPENBSD)
 			mandoc_msg(MANDOCERR_MDOCDATE_MISSING, n->line,
 			    n->pos, "Dd %s (OpenBSD)", n->string);
 	} else {
 		if (mdoc->meta.os_e == MANDOC_OS_NETBSD)
 			mandoc_msg(MANDOCERR_MDOCDATE, n->line,
 			    n->pos, "Dd %s (NetBSD)", n->string);
 	}
 }
 
 enum roff_sec
 mdoc_a2sec(const char *p)
 {
 	int		 i;
 
 	for (i = 0; i < (int)SEC__MAX; i++)
 		if (secnames[i] && 0 == strcmp(p, secnames[i]))
 			return (enum roff_sec)i;
 
 	return SEC_CUSTOM;
 }
 
 static size_t
 macro2len(enum roff_tok macro)
 {
 
 	switch (macro) {
 	case MDOC_Ad:
 		return 12;
 	case MDOC_Ao:
 		return 12;
 	case MDOC_An:
 		return 12;
 	case MDOC_Aq:
 		return 12;
 	case MDOC_Ar:
 		return 12;
 	case MDOC_Bo:
 		return 12;
 	case MDOC_Bq:
 		return 12;
 	case MDOC_Cd:
 		return 12;
 	case MDOC_Cm:
 		return 10;
 	case MDOC_Do:
 		return 10;
 	case MDOC_Dq:
 		return 12;
 	case MDOC_Dv:
 		return 12;
 	case MDOC_Eo:
 		return 12;
 	case MDOC_Em:
 		return 10;
 	case MDOC_Er:
 		return 17;
 	case MDOC_Ev:
 		return 15;
 	case MDOC_Fa:
 		return 12;
 	case MDOC_Fl:
 		return 10;
 	case MDOC_Fo:
 		return 16;
 	case MDOC_Fn:
 		return 16;
 	case MDOC_Ic:
 		return 10;
 	case MDOC_Li:
 		return 16;
 	case MDOC_Ms:
 		return 6;
 	case MDOC_Nm:
 		return 10;
 	case MDOC_No:
 		return 12;
 	case MDOC_Oo:
 		return 10;
 	case MDOC_Op:
 		return 14;
 	case MDOC_Pa:
 		return 32;
 	case MDOC_Pf:
 		return 12;
 	case MDOC_Po:
 		return 12;
 	case MDOC_Pq:
 		return 12;
 	case MDOC_Ql:
 		return 16;
 	case MDOC_Qo:
 		return 12;
 	case MDOC_So:
 		return 12;
 	case MDOC_Sq:
 		return 12;
 	case MDOC_Sy:
 		return 6;
 	case MDOC_Sx:
 		return 16;
 	case MDOC_Tn:
 		return 10;
 	case MDOC_Va:
 		return 12;
 	case MDOC_Vt:
 		return 12;
 	case MDOC_Xr:
 		return 10;
 	default:
 		break;
 	};
 	return 0;
 }