Re: [PATCH] Avoid uninitialized warning in i386.c

[Marek Polacek]

On Wed, Dec 18, 2013 at 02:45:12PM +0100, Jakub Jelinek wrote:
> On Wed, Dec 18, 2013 at 02:39:44PM +0100, Marek Polacek wrote:
> > Bootstrap with -fsanitize=undefined revealed that the alg variable
> > may be used uninitialized.  Or at least gcc thinks so.  This patch
> > initializes it to 0.
> > 
> > Regtested/bootstrapped on x86_64-linux, ok for trunk?
> 
> Do
>       stringop_alg alg = last_alg;
> instead, or alternatively (perhaps better), remove the alg variable
> altogether, just break; in the loop and set
>   input_ranges[n].alg = (stringop_alg) i;

Okay.  Regtested/bootstrapped on x86_64-linux, ok now?

2013-12-18  Marek Polacek  <pola...@redhat.com>

        * config/i386/i386.c (ix86_parse_stringop_strategy_string): Remove
        variable alg.  Use index variable i directly.

--- gcc/config/i386/i386.c.mp   2013-12-18 13:38:21.908138307 +0100
+++ gcc/config/i386/i386.c      2013-12-18 16:24:37.034353633 +0100
@@ -2856,7 +2856,6 @@ ix86_parse_stringop_strategy_string (cha
   do
     {
       int maxs;
-      stringop_alg alg;
       char alg_name[128];
       char align[16];
       next_range_str = strchr (curr_range_str, ',');
@@ -2879,13 +2878,8 @@ ix86_parse_stringop_strategy_string (cha
         }
 
       for (i = 0; i < last_alg; i++)
-        {
-          if (!strcmp (alg_name, stringop_alg_names[i]))
-            {
-              alg = (stringop_alg) i;
-              break;
-            }
-        }
+       if (!strcmp (alg_name, stringop_alg_names[i]))
+         break;
 
       if (i == last_alg)
         {
@@ -2896,7 +2890,7 @@ ix86_parse_stringop_strategy_string (cha
         }
 
       input_ranges[n].max = maxs;
-      input_ranges[n].alg = alg;
+      input_ranges[n].alg = (stringop_alg) i;
       if (!strcmp (align, "align"))
         input_ranges[n].noalign = false;
       else if (!strcmp (align, "noalign"))

        Marek