Sirraide 1381ef49fc [Clang] Add flags and lang option for C++2d (#203992) ...

This adds diagnostic groups, command-line options, a language option,
and various other things required to support `-std=c++2d`. I haven’t
touched e.g. clang-tidy or clang-format, as I’m not really familiar w/
either. This is only meant to add the most necessary parts to support
C++29 mode.

I grepped for `CPlusPlus26`/`C++26`/`C++2c` and updated all places I
could find where we need to handle every language mode in some way or
another.

This patch is roughly based on b763d6a4ed.

2026-07-03 21:37:02 +00:00

..

clang.rst

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diagtool.rst

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index.rst

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