llvm-project/clang/test/Preprocessor/pragma_unknown.c

// RUN: %clang_cc1 -E %s | grep '#pragma foo bar'
// RUN: %clang_cc1 -fsyntax-only -Wunknown-pragmas -verify %s

// GCC doesn't expand macro args for unrecognized pragmas.
#define bar xX
#pragma foo bar   // expected-warning {{unknown pragma ignored}}

#pragma STDC FP_CONTRACT ON
#pragma STDC FP_CONTRACT OFF
#pragma STDC FP_CONTRACT DEFAULT
#pragma STDC FP_CONTRACT IN_BETWEEN  // expected-warning {{expected 'ON' or 'OFF' or 'DEFAULT' in pragma}}

#pragma STDC FENV_ACCESS ON          // expected-warning {{pragma STDC FENV_ACCESS ON is not supported, ignoring pragma}}
#pragma STDC FENV_ACCESS OFF
#pragma STDC FENV_ACCESS DEFAULT
#pragma STDC FENV_ACCESS IN_BETWEEN   // expected-warning {{expected 'ON' or 'OFF' or 'DEFAULT' in pragma}}

#pragma STDC CX_LIMITED_RANGE ON
#pragma STDC CX_LIMITED_RANGE OFF
#pragma STDC CX_LIMITED_RANGE DEFAULT 
#pragma STDC CX_LIMITED_RANGE IN_BETWEEN   // expected-warning {{expected 'ON' or 'OFF' or 'DEFAULT' in pragma}}

#pragma STDC CX_LIMITED_RANGE    // expected-warning {{expected 'ON' or 'OFF' or 'DEFAULT' in pragma}}
#pragma STDC CX_LIMITED_RANGE ON FULL POWER  // expected-warning {{expected end of macro in STDC pragma}}

#pragma STDC SO_GREAT  // expected-warning {{unknown pragma in STDC namespace}}
#pragma STDC   // expected-warning {{unknown pragma in STDC namespace}}