Issue with append_coverage_compiler_flags_to_target (but with solution)

[MuellerSeb]

Hi there and thanks for this amazing repo!

I was trying to cleanup my coverage workflow and tried to replace append_coverage_compiler_flags with append_coverage_compiler_flags_to_target.

Two problems came across:

1. I needed to replace (CodeCoverage.cmake L717):

   target_compile_options(${name} PRIVATE ${COVERAGE_COMPILER_FLAGS})

   with:

   separate_arguments(_flag_list NATIVE_COMMAND "${COVERAGE_COMPILER_FLAGS}")
   target_compile_options(${name} PRIVATE ${_flag_list})

   Since the white spaces were not recognized to split the flags everything was append to -g which resulted in:

   error: unrecognized debug output level ' -fprofile-arcs -ftest-coverage'

2. Doing the above, I got another error, because the lib was not linked against gcov. So I could solve this by replacing:

   append_coverage_compiler_flags_to_target(${LIB_NAME})

   with:

   target_compile_options(${LIB_NAME} PRIVATE -g --coverage)
   target_link_libraries(${LIB_NAME} PRIVATE gcov)

   Note, that --coverage is equivalent to -fprofile-arcs -ftest-coverage (when compiling) and -lgcov (when linking). link

Maybe it could be a good idea to replace:

function(append_coverage_compiler_flags_to_target name)
    target_compile_options(${name}
        PRIVATE ${COVERAGE_COMPILER_FLAGS})
endfunction()

with

function(append_coverage_compiler_flags_to_target name)
    separate_arguments(_flag_list NATIVE_COMMAND "${COVERAGE_COMPILER_FLAGS}")
    target_compile_options(${name} PRIVATE ${_flag_list})
    target_link_libraries(${name} PRIVATE gcov)
endfunction()

And maybe we could also replace -fprofile-arcs -ftest-coverage with --coverage.

Cheers, Sebastian