This change makes `std::lock_guard` available when
`_LIBCPP_HAS_NO_THREADS` is set. This class is generic and doesn't
require threading support, and is regularly used even in environments
where threading isn't available like embedded.
fixes#89891
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Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Libc++ has no separate C++98 support, it uses C++03 instead. This
removes some obsolete c++98 markers in the test.
Thanks to @StephanTLavavej for spotting this.
There are a handful of standard library types that are intended
to support CTAD but don't need any explicit deduction guides to
do so.
This patch adds a dummy deduction guide to those types to suppress
-Wctad-maybe-unsupported (which gets emitted in user code).
This is a re-application of the original patch by Eric Fiselier in
fcd549a7d828 which had been reverted due to reasons lost at this point.
I also added the macro to a few more types. Reviving this patch was
prompted by the discussion on https://llvm.org/D133425.
Differential Revision: https://reviews.llvm.org/D133535
