1//===-- lib/Semantics/check-return.cpp ------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "check-return.h"
10#include "flang/Parser/message.h"
11#include "flang/Parser/parse-tree.h"
12#include "flang/Semantics/semantics.h"
13#include "flang/Semantics/tools.h"
14#include "flang/Support/Fortran-features.h"
15
16namespace Fortran::semantics {
17
18static const Scope *FindContainingSubprogram(const Scope &start) {
19 const Scope &scope{GetProgramUnitContaining(start)};
20 return scope.kind() == Scope::Kind::MainProgram ||
21 scope.kind() == Scope::Kind::Subprogram
22 ? &scope
23 : nullptr;
24}
25
26void ReturnStmtChecker::Leave(const parser::ReturnStmt &returnStmt) {
27 // R1542 Expression analysis validates the scalar-int-expr
28 // C1574 The return-stmt shall be in the inclusive scope of a function or
29 // subroutine subprogram.
30 // C1575 The scalar-int-expr is allowed only in the inclusive scope of a
31 // subroutine subprogram.
32 const auto &scope{context_.FindScope(context_.location().value())};
33 if (const auto *subprogramScope{FindContainingSubprogram(scope)}) {
34 if (returnStmt.v &&
35 (subprogramScope->kind() == Scope::Kind::MainProgram ||
36 IsFunction(*subprogramScope->GetSymbol()))) {
37 context_.Say(
38 "RETURN with expression is only allowed in SUBROUTINE subprogram"_err_en_US);
39 } else if (subprogramScope->kind() == Scope::Kind::MainProgram) {
40 context_.Warn(common::LanguageFeature::ProgramReturn,
41 "RETURN should not appear in a main program"_port_en_US);
42 }
43 }
44}
45
46} // namespace Fortran::semantics
47

source code of flang/lib/Semantics/check-return.cpp