[clang] [Clang] Fix crash with implicit int-to-pointer conversion (PR #114218)

[Oliver Stannard via cfe-commits]

ostannard wrote:

> If __atomic_test_and_set is overloaded to have both a volatile and non-volatile variant, it should be using custom type-checking in Sema.

Looking at the code again, there's a separate system used to codegen most of the atomic builtins, so I've switched to using that. That completely replaces this change, so I've started a new PR #120449, and will close this one.

> I had asked about this in the original PR here: https://github.com/llvm/llvm-project/pull/84146 but did not get a response.

I've added a comment there.

https://github.com/llvm/llvm-project/pull/114218