modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/builtin-constant.c (about) 1 /* PR optimization/8423. */ 2 3 #define btest(x) __builtin_constant_p(x) ? "1" : "0" 4 5 #ifdef __OPTIMIZE__ 6 void 7 foo (char *i) 8 { 9 if (*i == '0') 10 abort (); 11 } 12 #else 13 void 14 foo (char *i) 15 { 16 } 17 #endif 18 19 int 20 main (void) 21 { 22 int size = sizeof (int); 23 foo (btest (size)); 24 foo (btest (size)); 25 exit (0); 26 }