clang/test/Modules/Inputs/merge-target-features/foo.h - llvm-project - Git at Google

 #ifndef FOO_H
 #define FOO_H

 int foo(int x) {
   return x + 42;
 }

 #endif // FOO_H
	#ifndef FOO_H
	#define FOO_H

	int foo(int x) {
	return x + 42;
	}

	#endif // FOO_H