From f5ea0499a411309014475dc7f7983e827f431af2 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Fri, 27 Jan 2012 22:02:31 +0100
Subject: [PATCH] Build with `-fno-strict-aliasing' when available.

* configure.ac (POTENTIAL_GCC_CFLAGS): Add `-fno-strict-aliasing'.
  Suggested by Mark H. Weaver.
---
 configure.ac | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 04553755b..ccc5fa572 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1527,9 +1527,14 @@ case "$GCC" in
     ## and it became equally exasperating (gcc 2.95 and/or glibc 2.1.2).
     ## -Wundef was removed because Gnulib prevented it (see
     ## <http://thread.gmane.org/gmane.lisp.guile.bugs/5329>.)
+
+    ## Build with `-fno-strict-aliasing' to prevent miscompilation on
+    ## some platforms.  See
+    ## <http://lists.gnu.org/archive/html/guile-devel/2012-01/msg00487.html>.
+
     POTENTIAL_GCC_CFLAGS="-Wall -Wmissing-prototypes \
       -Wdeclaration-after-statement \
-      -Wswitch-enum"
+      -Wswitch-enum -fno-strict-aliasing"
     # Do this here so we don't screw up any of the tests above that might
     # not be "warning free"
     if test "${GUILE_ERROR_ON_WARNING}" = yes
-- 
2.20.1