[Bug c/29613] New: static string in vararg function

["etienne_lorrain at yahoo dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

When executing that on a target:
>>>>>>>>>>>>>>>>>>>>>>
#include <stdarg.h>

void bug_vsprintf( char *pString, const char *format, va_list ap)
{
        char c;
        char *str = 0;
        int str_cnt = 0;

        while((c = *format++) != '\0')
        {
                if (c == '%')
                {
                        if (*format++ == 's')
                        {
                                str = va_arg(ap, char *);
                                if (str == 0) str = "(null)";
                                for (str_cnt = 0; str[str_cnt] != '\0' &&
str_cnt <= 5; str_cnt++)
                                        continue;
                                if (str_cnt > 5) {
                                        static char errmsg[32] = "(invalid %s
ptr)";
                                        //char errmsg[32] = "(invalid %s ptr)";
// no bug
                                        str = errmsg;
                                        str_cnt = sizeof("(invalid %s ptr)") -
1;
                                        }
                        }


                        while(str_cnt)
                        {
                                *pString++ = (*str++);
                                str_cnt--;
                        }
                }
                else
                        *pString++ = c;
        }

        *pString = '\0';

}

void bug_sprintf( char *pString, const char *format, ...)
{
        va_list argptr;

        va_start( argptr, format );
        bug_vsprintf( pString, format, argptr );
        va_end( argptr );
}

void triggerbug(void)
{
        char buffer[50];
        bug_sprintf(buffer, "%s", "123456789");
        printf ("buggy buffer: %s i.e. 0x%X 0x%X 0x%X ...\r\n", buffer,
buffer[0], buffer[1], buffer[2]);
}

<<<<<<<<<<<<<
 (first include stdio.h for printf)
Compilation switch:
powerpc-eabi-gcc -Wall -W -O2 -fno-strict-aliasing -ffunction-sections
-std=gnu99 -Xassembler -mregnames bug.c

  I get the line:
buggy buffer: À i.e. 0xC0 0x0 0x57 ...
  If I remove the static (in "static char errmsg"), I get what I want:
buggy buffer: (invalid %s ptr) i.e. 0x28 0x69 0x6E ...


-- 
           Summary: static string in vararg function
           Product: gcc
           Version: 4.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: etienne_lorrain at yahoo dot fr
  GCC host triplet: cygwin-ia32
GCC target triplet: powerpc-eabi


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29613