a0a1f519c0
If the pure context check succeeds, call `WhyNotModifiable` to verify the LHS can be modified. Detect assignment to whole assumed-size array. Change `IsVariable` to return false for a parameter or a component or array reference whose base it a parameter. When analyzing an assignment statement, report an error if the LHS is a constant expression. Otherwise it might get folded and when we detect the problem later the error will be confusing. Handle Substring on LHS of assignment. Change ExtractDataRef and IsVariable to work on a Substring. Fix IsImpliedShape and IsAssumedSize predicates in ArraySpec. Fix C709 check in check-declarations.cpp. Original-commit: flang-compiler/f18@f2d2657aab Reviewed-on: https://github.com/flang-compiler/f18/pull/1050