From: Nathan Phillip Brink <binki@gentoo.org>
Date: 2011-07-09
Subject: Pass through extra compiler flags (so that portage-multilib
	can work by passing through -m32). Pulled and modified from libtool-2.2's
	ltmain.sh and altered for libtool-1.4.

--- a/ltmain.sh
+++ b/ltmain.sh
@@ -1187,8 +1187,25 @@
       -Xlinker)
 	prev=xlinker
 	continue
 	;;
 
+      # Flags to be passed through unchanged, with rationale:
+      # -64, -mips[0-9]      enable 64-bit mode for the SGI compiler
+      # -r[0-9][0-9]*        specify processor for the SGI compiler
+      # -xarch=*, -xtarget=* enable 64-bit mode for the Sun compiler
+      # +DA*, +DD*           enable 64-bit mode for the HP compiler
+      # -q*                  compiler args for the IBM compiler
+      # -m*, -t[45]*, -txscale* architecture-specific flags for GCC
+      # -F/path              path to uninstalled frameworks, gcc on darwin
+      # -p, -pg, --coverage, -fprofile-*  profiling flags for GCC
+      # @file                GCC response files
+      # -tp=*                Portland pgcc target processor selection
+      -64|-mips[0-9]|-r[0-9][0-9]*|-xarch=*|-xtarget=*|+DA*|+DD*|-q*|-m*| \
+      -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*)
+        arg=`$echo "X$arg" | $Xsed -e "$sed_quote_subst"`
+        compiler_flags="$compiler_flags $arg"
+        ;;
+
       # Some other compiler flag.
       -* | +*)
 	# Unknown arguments in both finalize_command and compile_command need