[SOLVED] How to set different warning levels for different files?

How to set different warning levels for different files?

While I can set different warning levels depending on the compiler, e.g.:

if(MSVC)
  target_compile_options(${TARGET_NAME} PRIVATE /W4 /WX)
else()
  target_compile_options(${TARGET_NAME} PRIVATE -Wall -Wextra -pedantic -Werror)
endif()

I cannot set them on a file by file basis.

In the same directory, I have a set of files whose names are in the ${SRC_WARN} CMake variable, which need a different warning level compared to the others.

Is there a way to specify such a condition with target_compile_options?

Solution

You can set compile options (COMPILE_OPTIONS) for a single file (or group of files) using set_source_files_properties(). You can change the COMPILE_OPTIONS for your ${SRC_WARN} source files by adding to your existing CMake code:

if(MSVC)
  target_compile_options(${TARGET_NAME} PRIVATE /W4 /WX)
  # Change these files to have warning level 2.
  set_source_files_properties(${SRC_WARN} PROPERTIES COMPILE_OPTIONS /W2)
else()
  target_compile_options(${TARGET_NAME} PRIVATE -Wall -Wextra -pedantic -Werror)
  # Change these files to inhibit all warnings.
  set_source_files_properties(${SRC_WARN} PROPERTIES COMPILE_OPTIONS -w)
endif()