[clang] [Clang] Add support for GCC bound member functions extension (PR #135649)

[Richard Smith via cfe-commits]

zygoloid wrote:

> We don't know which function is called until the object `p` is provided. See case 2 in https://discourse.llvm.org/t/rfc-implement-gcc-bound-pmf-in-clang/85951.

Perhaps we could provide a builtin function that takes an object pointer and a pointer-to-member-function and returns a devirtualized pointer-to-member-function (or returns the original PMF if it wasn't a pointer to a virtual function)? Unlike the GCC extension, that kind of interface can actually work in general.

https://github.com/llvm/llvm-project/pull/135649