From 75e20fd02b75d6236a6da0f61478ea06a9bcd8b6 Mon Sep 17 00:00:00 2001
From: smatz <smatz@openttd.org>
Date: Sun, 11 Nov 2012 17:39:54 +0000
Subject: [PATCH] (svn r24701) -Fix [FS#5246]: Workaround an overoptimisation
 done by GCC 4.5

---
 config.lib | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/config.lib b/config.lib
index 55dbc9a16a..6f215455aa 100644
--- a/config.lib
+++ b/config.lib
@@ -1350,6 +1350,12 @@ make_compiler_cflags() {
 			cxxflags="$cxxflags -std=gnu++0x"
 		fi
 
+		if [ $cc_version -eq 45 ]; then
+			# Prevent optimisation supposing enums are in a range specified by the standard
+			# For details, see http://gcc.gnu.org/PR43680
+			flags="$flags -fno-tree-vrp"
+		fi
+
 		if [ $cc_version -ge 47 ]; then
 			# Disable -Wnarrowing which gives many warnings, such as:
 			# warning: narrowing conversion of '...' from 'unsigned int' to 'int' inside { } [-Wnarrowing]