llvm-project

6b92a3bc - [flang][OpenMP] Detect BLOCK construct through lookahead (#150617)

[flang][OpenMP] Detect BLOCK construct through lookahead (#150617) Avoid parsing the entire ExecutionPartConstruct in either the strictly- or the loosely-structured block parser only to discard it when it's not BLOCK (or is BLOCK) respectively. Doing so was not incorrct, but in pathological cases (like Fujitsu 0981_0034) the recursive parsing can take a very long time. Instead, detect the presence of BLOCK first (via a simple lookahead), and fail immediately if necessary.