[llvm-branch-commits] [llvm] release/21.x: [llvm] Support building with c++23 (#154372) (PR #162510)

[Nikita Popov via llvm-branch-commits]

https://github.com/nikic commented:

I'm not comfortable backporting this given the amount of changes to exported headers.

https://github.com/llvm/llvm-project/pull/162510