[clang] [clang] Prevent stack overflow on deeply nested template arguments (PR #224393)

[Younan Zhang via cfe-commits]

https://github.com/zyn0217 commented:

I'm reluctant to accept the patch as-is, though the latest approach makes sense.

I want to question if people would write such paranoid recursive template arguments in real world codebase - the issue was fuzzer generated.

I'm not saying this is not a bug, I wonder if doing so would also require us to revisit every recursive calls and add guards here and there?

https://github.com/llvm/llvm-project/pull/224393