Tests/PrecompiledHeader/foo1.c - third_party/cmake - Git at Google

 #ifndef foo_h
 #  error "Precompiled header foo_precompiled.h has not been loaded."
 #endif

 int main()
 {
   return foo();
 }
	#ifndef foo_h
	# error "Precompiled header foo_precompiled.h has not been loaded."
	#endif

	int main()
	{
	return foo();
	}