1 #pragma GCC system_header 2 system_header_func(int x)3inline int system_header_func(int x) 4 __attribute__((diagnose_if(x == x, "system header warning", "warning"))) // expected-note {{from 'diagnose_if' attribute}} 5 { 6 return 0; 7 } 8 test_system_header()9void test_system_header() { 10 system_header_func(0); // expected-warning {{system header warning}} 11 } 12