Merge topic 'compiler_flags'
f76c20da63 Toolchain: Test compiler initial settings
db486da265 Toolchain: Update documentation for initial compiler flags
deec2f587c Toolchain: Take CMAKE_<lang>_FLAGS_INIT into account during compiler detection
ca899af3e2 Toolchain: Handle repeated invocations of CMake with -DCMAKE_C_COMPILER
12ba89e142 Toolchain: Make `/path/comp;-argn' behave the same as 'comp;-argn'
6f1af899db Toolchain: Capture all arguments from CMAKE_<LANG>_COMPILER
ec1d3bc0b6 cmake: avoid exception when printing "changed variables" message
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !4136
