commit c82f5c0ce5c1c0180fca311ceb29fd2d59da7441
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Wed Nov 26 00:45:19 2014 +0000
 
    Fix warning in setjmp/jmpbug.c.
    
    This patch fixes a "set but not used" warning in setjmp/jmpbug.c.  A
    variable is used only to store the result of alloca.  A cast to void
    is added to avoid the warning, and the variable is made volatile to
    ensure the call to alloca isn't optimized away for being unused.
    
    Tested for x86_64.
    
            * setjmp/jmpbug.c (test): Make foo volatile and cast it to
            void.
 
diff --git a/setjmp/jmpbug.c b/setjmp/jmpbug.c
index 125977b2f719dbeb..8594c5a8a782b218 100644
--- a/setjmp/jmpbug.c
+++ b/setjmp/jmpbug.c
@@ -14,7 +14,7 @@ static void
 test (int x)
 {
   jmp_buf buf;
-  char *foo;
+  char *volatile foo;
   int arr[100];
 
   arr[77] = x;
@@ -25,6 +25,7 @@ test (int x)
     }
 
   foo = (char *) alloca (128);
+  (void) foo;
   sub5 (buf);
 }