[clang] [llvm] [clang][ARM] Add -fstack-limit-variable to trap before stack overflow (PR #208076)

[Eli Friedman via cfe-commits]

https://github.com/efriedma-quic commented:

Checking like this seems really expensive in both size and runtime performance.  I'm a little skeptical this is actually usable.

Is something like -fstack-clash-protection not usable in this context?

https://github.com/llvm/llvm-project/pull/208076