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* [Bug c/42406]  New: gcc issues warning with tolower function with optimization flag
@ 2009-12-17 15:02 joe dot bassis at gmail dot com
  2009-12-17 16:20 ` [Bug c/42406] " rguenth at gcc dot gnu dot org
  0 siblings, 1 reply; 2+ messages in thread
From: joe dot bassis at gmail dot com @ 2009-12-17 15:02 UTC (permalink / raw)
  To: gcc-bugs

gcc issues warning when using the tolower function along with an optimization
flag. This warning also happens in other versions of gcc apart from 4.4.2

gcc -std=c99 -pedantic -O2 -Wall -Wunreachable-code a.c

a.c:13: warning: will never be executed



#include <stdio.h>
#include <string.h>
#include <ctype.h>

int main(void)
{
    char A[50] = "";
    strcat(A, "Hello World!");

    int COUNT = 0;
    while(A[COUNT])
    {
        A[COUNT] = (char)(tolower(A[COUNT])); // this line issues warning
        COUNT++;
    }
    puts(A); // output: hello world!
    return 0;
}


-- 
           Summary: gcc issues warning with tolower function with
                    optimization flag
           Product: gcc
           Version: 4.4.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: joe dot bassis at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42406


^ permalink raw reply	[flat|nested] 2+ messages in thread
* [Bug c/42406] gcc issues warning with tolower function with optimization flag
  2009-12-17 15:02 [Bug c/42406] New: gcc issues warning with tolower function with optimization flag joe dot bassis at gmail dot com
@ 2009-12-17 16:20 ` rguenth at gcc dot gnu dot org
  0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-12-17 16:20 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #1 from rguenth at gcc dot gnu dot org  2009-12-17 16:20 -------
-Wunreachable-code is broken and has been removed in 4.5.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WONTFIX


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42406


^ permalink raw reply	[flat|nested] 2+ messages in thread
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2009-12-17 15:02 [Bug c/42406] New: gcc issues warning with tolower function with optimization flag joe dot bassis at gmail dot com
2009-12-17 16:20 ` [Bug c/42406] " rguenth at gcc dot gnu dot org

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