clang/test/Preprocessor/empty_va_arg.cpp

   1 // RUN: %clang_cc1 -Eonly -std=c17 -pedantic -verify=c17,expected -x c %s
   2 // RUN: %clang_cc1 -Eonly -std=c23 -pedantic -Wpre-c23-compat -verify=c23,expected -x c %s
   3 // RUN: %clang_cc1 -Eonly -std=c++17 -pedantic -verify=cxx17,expected %s
   4 // RUN: %clang_cc1 -Eonly -std=c++20 -pedantic -Wpre-c++20-compat -verify=cxx20,expected %s
   5
   6 // silent-no-diagnostics
   7
   8 #define FOO(x, ...) // expected-note  {{macro 'FOO' defined here}}
   9
  10 int main() {
  11   FOO(42) // c17-warning {{passing no argument for the '...' parameter of a variadic macro is a C23 extension}} \
  12           // cxx17-warning {{passing no argument for the '...' parameter of a variadic macro is a C++20 extension}} \
  13           // c23-warning {{passing no argument for the '...' parameter of a variadic macro is incompatible with C standards before C23}} \
  14           // cxx20-warning {{passing no argument for the '...' parameter of a variadic macro is incompatible with C++ standards before C++20}}
  15 }
  16