[clang] [CIR] Upstream ArraySubscriptExpr for fixed size array (PR #134536)

[Erich Keane via cfe-commits]

https://github.com/erichkeane commented:

This also seems to be missing a  test that does:

C++->CIR
C++->CIR->LLVM
C++->LLVM

all in teh same file?  (See files iwth `OGCG` in them).

https://github.com/llvm/llvm-project/pull/134536