Compilation fails using Clang 17 toolchain

MSYS2 just updated their clang and associated packages to 17.0.1. We are now seeing the following compilation error:

   17 | #  include <__std_stream>

     |            ^~~~~~~~~~~~~~

This seems to be related to the following change in libcxx: https://reviews.llvm.org/D147855

[vitaut]

Removed the nonportable include in 2dd4fa8. Thanks for reporting.

[lazka]

Note that there is still one include left here:

fmt/src/fmt.cc

Lines 66 to 68 in 79dbd3f

	# elif defined(_LIBCPP_VERSION)
	# include <__std_stream>
	# endif

which makes the build with "cmake -DFMT_MODULE=ON" fail.

[vitaut]

@lazka, could you submit a PR to remove it too?

[lazka]

sure, #3663

[Roman-Koshelev]

@vitaut wouldn't it make more sense to leave this hack for libc++ < 17? (native_handle() should be at 18)

[vitaut]

I don't think it's worth spending any efforts on conditionally supporting this hack for iostreams which are a legacy API.