[clang] [Clang] Allow malloc and alloc_size attributes for functions returning structs (PR #165433)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman commented:

> Since this attribute was originally defined by gcc, we should consult with gcc devs to see if they have a position on this. It would be a proble if gcc chooses some different behavior here.

+1 to this request

https://github.com/llvm/llvm-project/pull/165433