20 lines · c
1#if defined(CLANG)2#pragma clang system_header3// expected-no-diagnostics4#elif defined(GCC)5#pragma GCC system_header6// expected-no-diagnostics7#elif defined(MS)8#pragma system_header9// expected-no-diagnostics10#else11// expected-warning@+1{{unknown pragma ignored}}12#pragma system_header13 14// expected-note@+4{{previous definition is here}}15// expected-warning@+4{{redefinition of typedef 'x' is a C11 feature}}16#endif17 18typedef int x;19typedef int x;20