Tests/RunCMake/NinjaMultiConfig/PerConfigSources.cmake - third_party/cmake - Git at Google

 enable_language(C)
 file(GENERATE OUTPUT "${CMAKE_BINARY_DIR}/main_$<CONFIG>.c" CONTENT
 [[int main(void)
 {
   return 0;
 }
 ]])
 add_executable(exe "${CMAKE_BINARY_DIR}/main_$<CONFIG>.c")
	enable_language(C)
	file(GENERATE OUTPUT "${CMAKE_BINARY_DIR}/main_$<CONFIG>.c" CONTENT
	[[int main(void)
	{
	return 0;
	}
	]])
	add_executable(exe "${CMAKE_BINARY_DIR}/main_$<CONFIG>.c")