gcc/testsuite/gcc.dg/charset/builtin1.c

   1 /* isdigit(c) can be optimized to ((unsigned)c) - '0' <= 9, but only if
   2    we know the correct value of '0'.  PR 18785.  */
   3
   4 /* { dg-do run } */
   5 /* { dg-options "-O2 -fno-inline -fexec-charset=IBM-1047" } */
   6
   7 extern int isdigit(int);
   8 extern void abort(void);
   9
  10 static int str1(void) { return '1'; }
  11 static int strA(void) { return 'A'; }
  12
  13 int
  14 main(void)
  15 {
  16   if (!isdigit('1'))
  17     abort();
  18   if (isdigit('A'))
  19     abort();
  20   if (!isdigit(str1()))
  21     abort();
  22   if (isdigit(strA()))
  23     abort();
  24   return 0;
  25 }