glibc/string/bug-strncat1.c
Adhemerval Zanella Netto 85ac7edcdf string: Fix bug-strncat1 with fortify enabled
If fortify is enabled, the truncated output warning is issued by
the wrapper itself:

bug-strncat1.c: In function ‘main’:
bug-strncat1.c:14:3: error: ‘__builtin___strncat_chk’ output truncated
copying 1 byte from a string of length 2 [-Werror=stringop-truncation]
   14 |   strncat (d, "\5\6", 1);
      |   ^

Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-07-24 15:26:17 -03:00

41 lines
771 B
C

#undef __USE_STRING_INLINES
#define __USE_STRING_INLINES
#include <sys/cdefs.h>
#include <libc-diag.h>
#if __GNUC_PREREQ (8, 0)
/* GCC warns about strncat truncating output; this is deliberately
tested here. If fortify is enabled, it is also triggered by the
wrappers. */
DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation");
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char d[3] = "\0\1\2";
int
main (void)
{
DIAG_PUSH_NEEDS_COMMENT;
strncat (d, "\5\6", 1);
DIAG_POP_NEEDS_COMMENT;
if (d[0] != '\5')
{
puts ("d[0] != '\\5'");
exit (1);
}
if (d[1] != '\0')
{
puts ("d[1] != '\\0'");
exit (1);
}
if (d[2] != '\2')
{
puts ("d[2] != '\\2'");
exit (1);
}
return 0;
}