detecting if libc++ is present

Usage
1

I wanted to automatically set stdlib to libc++ when compiler is clang but I stumbled upon a machine where clang++ was present but

target_link_options(${TARGET_NAME} PUBLIC $<$<LINK_LANGUAGE:CXX>:-stdlib=libc++>)

emitted an error.
Thus I suppose that libc++ is not necessarily installed along clang++.

What would be the simplest way to test if libc++ can be used ?

Thanks in advance, Regards
A.
Addendum: It seems that certain configurations also require -lc++abi, how can I detect that?

2

I haven’t tried your case to see if there’s a straightforward way with find_library. However, in general when I need to test something that is easiest to do from a small project, I make a subdirectory and put a simple CMakeLists.txt. I then test that project at CMake configure time using try_compile from the main project.

Example where the fs_check directory is used via try_compile to ensure that c++ standard library filesystem is linkable and actually working. Because the feature check macros don’t always ensure that the standard library works for that particular case.

3

Thanks, it’s an idea but I’m afraid of the time overhead when reconfiguring the projects. I expected some more straightforward technic.
A.

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