[libcxx-commits] [libcxx] [libc++] Avoid -Wzero-as-null-pointer-constant in operator<=> (PR #79465)

[Martin Hořeňovský via libcxx-commits]

horenmar wrote:

I can eventually rip out enough internals from Catch2 to show the error, but I think this shows the issue in a much simpler form.

https://godbolt.org/z/KsP56vbs6

If you swap to the other definition of `Literal_Zero`, the compilation fails because the requires clause selects overload that can't actually compile.

Caveat: I don't know how Clang's diagnostic `__attribute__` added in the last commit works, and how it would change what happens, so this is about the version before that.

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I have also found that other people ran into this issue when MS/STL switched from the pointer-based constructor to int-based one and there is an open devcom ticket about it.


https://github.com/llvm/llvm-project/pull/79465