string/bug-strspn1.c

   1 /* Test case by Joseph S. Myers <jsm28@cam.ac.uk>.  */
   2 #undef __USE_STRING_INLINES
   3 #define __USE_STRING_INLINES
   4 #include <string.h>
   5 #include <stdlib.h>
   6 #include <stdio.h>
   7 #include <libc-diag.h>
   8
   9 int
  10 main (void)
  11 {
  12   const char *a = "abc";
  13   const char *b = a;
  14
  15   DIAG_PUSH_NEEDS_COMMENT;
  16   /* GCC 9 correctly warns that this call to strspn is useless.  That
  17      is deliberate; this test is verifying that a side effect in an
  18      argument still occurs when the call itself is useless and could
  19      be optimized to return a constant.  */
  20   DIAG_IGNORE_NEEDS_COMMENT (9, "-Wunused-value");
  21   strspn (b++, "");
  22   DIAG_POP_NEEDS_COMMENT;
  23   if (b != a + 1)
  24     return 1;
  25
  26   return 0;
  27 }