Index: Mk/bsd.gcc.mk
===================================================================
--- Mk/bsd.gcc.mk
+++ Mk/bsd.gcc.mk
@@ -17,6 +17,16 @@
 # do so by specifying USE_GCC=X.Y+ which requests at least GCC version
 # X.Y.  To request a specific version omit the trailing + sign.
 #
+# Optional comma-separated arguments may be specified after the version
+# specifier. The following arguments are supported:
+#	build	add GCC to BUILD_DEPENDS
+#	run		add GCC to RUN_DEPENDS
+#	test	add GCC to TEST_DEPENDS
+# if no arguments are specified, GCC is added to BUILD_DEPENDS and RUN_DEPENDS.
+#
+# USE_GCC=build, USE_GCC=run and USE_GCC=test are aliases to yes:build, yes:run
+# and yes:test, respectively.
+#
 # Examples:
 #   USE_GCC=	yes			# port requires a current version of GCC
 #							# as defined in bsd.default-versions.mk.
@@ -23,7 +33,10 @@
 #   USE_GCC=	any			# port requires GCC 4.2 or later.
 #   USE_GCC=	4.9+		# port requires GCC 4.9 or later.
 #   USE_GCC=	4.9			# port requires GCC 4.9.
-#
+#   USE_GCC=	4.9:build	# port requires GCC 4.9 at build-time only.
+#   USE_GCC=	build		# port requires a current version of GCC  at
+#							# build-time only.
+#
 # If you are wondering what your port exactly does, use "make test-gcc"
 # to see some debugging.
 #
@@ -52,6 +65,41 @@
 # No configurable parts below this. ####################################
 #

+# Alias {build,run,test} -> yes:{build,run,test}
+.if ${USE_GCC} == build || ${USE_GCC} == run || ${USE_GCC} == test
+USE_GCC:=		yes:${USE_GCC}
+.endif
+
+# Split args
+.if defined(USE_GCC)
+__USE_GCC:=		${USE_GCC:C/\:.*//}
+_USE_GCC_ARGS:=	${USE_GCC:C/^[^\:]*(\:|\$)//:S/,/ /g}
+USE_GCC=		${__USE_GCC}
+.endif # defined(USE_GCC)
+
+# Make sure that no dependency or some other environment variable
+# pollutes the build/run dependency detection
+.undef _USE_GCC_BUILD_DEP
+.undef _USE_GCC_RUN_DEP
+.undef _USE_GCC_TEST_DEP
+.if ${_USE_GCC_ARGS:Mbuild}
+_USE_GCC_BUILD_DEP=	yes
+.endif
+.if ${_USE_GCC_ARGS:Mrun}
+_USE_GCC_RUN_DEP=	yes
+.endif
+.if ${_USE_GCC_ARGS:Mtest}
+_USE_GCC_TEST_DEP=	yes
+.endif
+
+# The port does not specify a build, run or test dependency, assume build and
+# test are required.
+.if !defined(_USE_GCC_BUILD_DEP) && !defined(_USE_GCC_RUN_DEP) && \
+    !defined(_USE_GCC_TEST_DEP) && !defined(USE_GCC_NO_DEPENDS)
+_USE_GCC_BUILD_DEP=	yes
+_USE_GCC_RUN_DEP=	yes
+.endif
+
 .if defined(USE_GCC) && ${USE_GCC} == yes
 USE_GCC=	${GCC_DEFAULT}+
 .endif
@@ -173,8 +221,15 @@
 .undef V

 .if defined(_GCC_PORT_DEPENDS)
+. if defined(_USE_GCC_BUILD_DEP)
 BUILD_DEPENDS+=	${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT}
+. endif
+. if defined(_USE_GCC_RUN_DEP)
 RUN_DEPENDS+=	${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT}
+. endif
+. if defined(_USE_GCC_TEST_DEP)
+TEST_DEPENDS+=	${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT}
+. endif
 # Later GCC ports already depend on binutils; make sure whatever we
 # build leverages this as well.
 USE_BINUTILS=	yes
@@ -188,11 +243,23 @@
 	@echo "IGNORE: ${IGNORE}"
 .else
 .if defined(USE_GCC)
+.if defined(_USE_GCC_ARGS)
+	@echo "ARGS: ${_USE_GCC_ARGS}"
+.endif
 .if defined(_GCC_ORLATER)
 	@echo Port can use later versions.
 .else
 	@echo Port cannot use later versions.
 .endif
+.if defined(_USE_GCC_BUILD_DEP)
+	@echo ${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT} will be added to BUILD_DEPENDS.
+.endif
+.if defined(_USE_GCC_RUN_DEP)
+	@echo ${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT} will be added to RUN_DEPENDS.
+.endif
+.if defined(_USE_GCC_TEST_DEP)
+	@echo ${_GCC_PORT_DEPENDS}:lang/${_GCC_PORT} will be added to TEST_DEPENDS.
+.endif
 .for v in ${GCCVERSIONS}
 	@echo -n "GCC version: ${_GCCVERSION_${v}_V} "
 .if defined(_GCC_FOUND${v})