changeset 7406:2618892a59f8 draft

(svn r10779) -Fix: GCC 4.2 makes (by default for -O2, -O3 and -Os) an assumption that signed integers do not overflow, whereas it is very likely that some of the legacy code does so. It furthermore breaks with the assumed standard (the behaviour is not actually defined in the standard) about the behaviour when signed integers wrap.
author rubidium <rubidium@openttd.org>
date Sat, 04 Aug 2007 00:45:53 +0000
parents 4aa2ed8e5f36
children 69bab9712028
files config.lib
diffstat 1 files changed, 8 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- a/config.lib
+++ b/config.lib
@@ -838,6 +838,14 @@
 		CFLAGS="$CFLAGS -fno-strict-aliasing"
 	fi
 
+	# GCC 4.2+ automatically assumes that signed overflows do
+	# not occur in signed arithmetics, whereas we are not
+	# sure that they will not happen. It furthermore complains
+	# about it's own optimized code in some places.
+	if [ $cc_version -ge 42 ]; then
+		CFLAGS="$CFLAGS -fno-strict-overflow"
+	fi
+
 	if [ "$os" != "CYGWIN" ] && [ "$os" != "FREEBSD" ] && [ "$os" != "OPENBSD" ] && [ "$os" != "MINGW" ] && [ "$os" != "MORPHOS" ] && [ "$os" != "OSX" ] && [ "$os" != "WINCE" ] && [ "$os" != "PSP" ] && [ "$os" != "OS2" ]; then
 		LIBS="$LIBS -lpthread"
 		LIBS="$LIBS -lrt"