Avoid leading dash in expr call

Message ID m2k45rtc7b.fsf@igel.home
State New
Headers show

Commit Message

Andreas Schwab Dec. 20, 2011, 4:55 p.m.
Andreas Tobler pointed out that passing a string with leading dash as
argument to expr is non-portable.  Checked in as obvious.


2011-12-20  Andreas Schwab  <schwab@linux-m68k.org>

	* warnings.m4 (ACX_PROG_CC_WARNING_OPTS): Avoid leading dash in
	expr call.


diff --git a/config/warnings.m4 b/config/warnings.m4
index 292e5a4..b64b594 100644
--- a/config/warnings.m4
+++ b/config/warnings.m4
@@ -32,7 +32,7 @@  for real_option in $1; do
   # Do the check with the no- prefix removed since gcc silently
   # accepts any -Wno-* option on purpose
   case $real_option in
-    -Wno-*) option=-W`expr $real_option : '-Wno-\(.*\)'` ;;
+    -Wno-*) option=-W`expr x$real_option : 'x-Wno-\(.*\)'` ;;
     *) option=$real_option ;;
   AS_VAR_PUSHDEF([acx_Woption], [acx_cv_prog_cc_warning_$option])