This removes all "TODO: remove these headers" comments from our headers.
Note there seem to be more headers that can be removed, that will be
done in separate commits.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D127592
All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.
Differential Revision: https://reviews.llvm.org/D121528
This avoids using an libc++ internal macro in our tests. This version
doesn't depend on the internal macro but redefines it.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D119460
Those creep up from time to time. We need to use `int main(int, char**)`
because in freestanding mode, `main` doesn't get special treatment and
special mangling, so we setup a symbol alias from the mangled version of
`main(int, char**)` to `extern "C" main`. That only works if all the tests
are consistent about how they define their main function.
Some embedded platforms do not wish to support the C library functionality
for handling wchar_t because they have no use for it. It makes sense for
libc++ to work properly on those platforms, so this commit adds a carve-out
of functionality for wchar_t.
Unfortunately, unlike some other carve-outs (e.g. random device), this
patch touches several parts of the library. However, despite the wide
impact of this patch, I still think it is important to support this
configuration since it makes it much simpler to port libc++ to some
embedded platforms.
Differential Revision: https://reviews.llvm.org/D111265
