hanchenye-llvm-project/clang/test/Modules/requires.m

// RUN: rm -rf %t
// RUN: %clang_cc1 -Wauto-import -fmodule-cache-path %t -fmodules -F %S/Inputs %s -verify

@__experimental_modules_import DependsOnModule.CXX; // expected-error{{module 'DependsOnModule.CXX' requires feature 'cplusplus'}}