[clang] [llvm] [SystemZ, Clang] Enable verification of int args extensions by default. (PR #223755)

[Nikita Popov via llvm-commits]

nikic wrote:

isInternal() exists because functions with local linkage are not required to follow the platform psABI. LLVM is free to change the ABI however it likes.

https://github.com/llvm/llvm-project/pull/223755