* configure.in: added -fno-strict-overflow. it suppress annoying

-Wstrict-overflow warning.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33872 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Sun Nov 27 21:25:33 2011  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
+
+	* configure.in: added -fno-strict-overflow. it suppress annoying
+	  -Wstrict-overflow warning.
+
 Sun Nov 27 20:58:02 2011  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
 
 	* io.c (rb_write_error2): get rid of warning on linux. fwrite

configure.in

@@ -496,7 +496,10 @@ if test "$GCC:${warnflags+set}:no" = yes::no; then
     warnflags=
 fi
 if test "$GCC" = yes; then
+    # -D_FORTIFY_SOURCE
     RUBY_TRY_CFLAGS(-D_FORTIFY_SOURCE=2, [RUBY_APPEND_OPTION(XCFLAGS, -D_FORTIFY_SOURCE=2)])
+
+    # -fstack-protector
     AS_CASE(["$target_os"],
     [mingw*], [
 	stack_protector=no
@@ -508,6 +511,9 @@ if test "$GCC" = yes; then
 	RUBY_APPEND_OPTION(XCFLAGS, -fstack-protector)
 	RUBY_APPEND_OPTION(XLDFLAGS, -fstack-protector)
     fi
+
+    # suppress annoying -Wstrict-overflow warnings
+    RUBY_TRY_CFLAGS(-fno-strict-overflow, [RUBY_APPEND_OPTION(XCFLAGS, -fno-strict-overflow)])
 fi
 
 if test "$GCC" = ""; then