Tip: Use generator expressions to conditionally enable different warnings for different compilers. This code will enable -Wall for GCC and clang and /W4 for MSVC. Target_compile_options ( my_library PRIVATE $, $, $ >: -Wall> $ : /W4> ) The above warnings will work on GCC and clang, but not MSVC.īefore you start doing if(), take a look at generator expressions:
This is a nice clean solution, the only issue is that the compiler flags are compiler dependent. Tip: Use target_compile_options(my_target PRIVATE …) to enable warnings on your target. On the contrast, targets linking to it will get the include directories and other libraries as they are PUBLIC. Targets linking to it will not get the warnings enabled. You can use that to specify warnings as well.Īnd as the warnings are specified as PRIVATE, they will only be used when compiling your library. With target_compile_options() you can also specify compiler flags for your target. When creating a library you specify include directories and link to other libraries. If -DCMAKE_CXX_FLAGS="…" is annoying, why not move it into the CMakeLists.txt?Īdd_library ( my_library … ) target_include_directories ( my_library PUBLIC include/ ) target_link_libraries ( my_library PUBLIC other_library ) target_compile_options ( my_library PRIVATE -Werror -Wall -Wextra ) Enabling Warnings by Modifying Target Properties So with my latest project, foonathan/lex, I looked for a better solution. This should also be reflected by the build files. I think this is problematic, because your code is designed with a certain warning level in mind. It decouples the warning options from your version control system and build files. You either have to remove -Werror or manually disable warnings on the external target somehow. This is problematic when you use add_subdirectory() to compile some external dependencies which do not compile without warnings. The warnings are used to compile everything with warnings enabled. There compilation failed due to warnings, which was annoying.
I occasionally forgot to do that, implemented a feature, pushed it to CI.
#CMAKE INCLUDE DIRECTORIES SYNTAX UPDATE#
You have to remember to manually update CMAKE_CXX_FLAGS on CI and on every locale development machine. While this approach definitely works, it has a couple of problems: That way the compiler will always have the warning flags enabled. Cmake -DCMAKE_CXX_FLAGS = "-Werror -Wall -Wextra …"
0 kommentar(er)
