llvm-project/flang/lib/Semantics/check-return.cpp

46 lines
1.8 KiB
C++

//===-- lib/Semantics/check-return.cpp ------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "check-return.h"
#include "flang/Common/Fortran-features.h"
#include "flang/Parser/message.h"
#include "flang/Parser/parse-tree.h"
#include "flang/Semantics/semantics.h"
#include "flang/Semantics/tools.h"
namespace Fortran::semantics {
static const Scope *FindContainingSubprogram(const Scope &start) {
const Scope &scope{GetProgramUnitContaining(start)};
return scope.kind() == Scope::Kind::MainProgram ||
scope.kind() == Scope::Kind::Subprogram
? &scope
: nullptr;
}
void ReturnStmtChecker::Leave(const parser::ReturnStmt &returnStmt) {
// R1542 Expression analysis validates the scalar-int-expr
// C1574 The return-stmt shall be in the inclusive scope of a function or
// subroutine subprogram.
// C1575 The scalar-int-expr is allowed only in the inclusive scope of a
// subroutine subprogram.
const auto &scope{context_.FindScope(context_.location().value())};
if (const auto *subprogramScope{FindContainingSubprogram(scope)}) {
if (returnStmt.v &&
(subprogramScope->kind() == Scope::Kind::MainProgram ||
IsFunction(*subprogramScope->GetSymbol()))) {
context_.Say(
"RETURN with expression is only allowed in SUBROUTINE subprogram"_err_en_US);
} else if (context_.ShouldWarn(common::LanguageFeature::ProgramReturn)) {
context_.Say("RETURN should not appear in a main program"_port_en_US);
}
}
}
} // namespace Fortran::semantics