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/* Verify that calls to a function declared wiith attribute format (printf)
don't get eliminated even if their result on success can be computed at
compile time (they can fail).
{ dg-require-effective-target unwrapped }
{ dg-require-effective-target fileio }
{ dg-prune-output "warning: warning: \[^\n\r\]* possibly used unsafely" }
{ dg-skip-if "requires io" { avr-*-* } }
{ dg-skip-if "requires io" { freestanding } } */
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "gcc_tmpnam.h"
void __attribute__ ((format (printf, 1, 2), noipa))
user_print (const char *fmt, ...)
{
va_list va;
va_start (va, fmt);
vfprintf (stdout, fmt, va);
va_end (va);
}
int main (void)
{
char *tmpfname = gcc_tmpnam (0);
FILE *f = freopen (tmpfname, "w", stdout);
if (!f)
{
perror ("fopen for writing");
return 1;
}
user_print ("1");
user_print ("%c", '2');
user_print ("%c%c", '3', '4');
user_print ("%s", "5");
user_print ("%s%s", "6", "7");
user_print ("%i", 8);
user_print ("%.1s\n", "9x");
fclose (f);
f = fopen (tmpfname, "r");
if (!f)
{
perror ("fopen for reading");
remove (tmpfname);
return 1;
}
char buf[12] = "";
if (1 != fscanf (f, "%s", buf))
{
perror ("fscanf");
fclose (f);
remove (tmpfname);
return 1;
}
fclose (f);
remove (tmpfname);
if (strcmp (buf, "123456789"))
abort ();
return 0;
}
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