When the result of a function never appears in a variable definition context, emit a warning. If the function has multiple result variables due to alternate ENTRY statements, any definition will suffice. The implementation of this check is tied to the general variable definability checking utility in semantics. Every variable definition context uses it to ensure that no undefinable variable is being defined. A set of defined variables is maintained in the SemanticsContext and, when the warning is enabled and no fatal error has been reported, the scope tree is traversed and all the function subprograms' results are tested for membership in that set.
21 KiB
21 KiB