On Fri, Jan 4, 2019 at 8:41 PM Richard Smith <rich...@metafoo.co.uk> wrote: > > On Fri, 4 Jan 2019 at 17:33, Nico Weber via cfe-commits > <cfe-commits@lists.llvm.org> wrote: >> >> Nice, this is finding bugs: >> https://bugs.chromium.org/p/chromium/issues/detail?id=919262 >> >> However, I noticed that for that case, the same warning is printed twice: >> >> ../../third_party/crashpad/crashpad/util/win/process_info.cc(227,36): >> error: expression result unused [-Werror,-Wunused-value] >> NTSTATUS_LOG(ERROR, status), "NtQueryInformationProcess"; >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~ >> ../../third_party/crashpad/crashpad/util/win/process_info.cc(227,36): >> error: expression result unused [-Werror,-Wunused-value] >> NTSTATUS_LOG(ERROR, status), "NtQueryInformationProcess"; >> >> >> Is that expected?
Yes and no. It's not unexpected, but it's not super helpful either. As Richard points out below, this happens because of template instantiation. > The first diagnostic appears when parsing the template, the second one > appears when instantiating it. In the complete diagnostic output: > > ../../third_party/crashpad/crashpad/util/win/process_info.cc(227,36): error: > expression result unused [-Werror,-Wunused-value] > NTSTATUS_LOG(ERROR, status), "NtQueryInformationProcess"; > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > > ../../third_party/crashpad/crashpad/util/win/process_info.cc(227,36): error: > expression result unused [-Werror,-Wunused-value] > NTSTATUS_LOG(ERROR, status), "NtQueryInformationProcess"; > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > ../../third_party/crashpad/crashpad/util/win/process_info.cc(531,17): note: > in instantiation of function template specialization > 'crashpad::GetProcessBasicInformation<crashpad::process_types::internal::Traits32>' > requested here > bool result = GetProcessBasicInformation<process_types::internal::Traits32>( > ^ > > It'd be nice to suppress the diagnostic during instantiation if it appeared > during the initial parse (generally, not with something specific to this > warning). Agreed, though I don't have the time to work on that currently. Hopefully the behavior here isn't too onerous for Chromium (or other projects)? ~Aaron > >> Code is here: >> https://cs.chromium.org/chromium/src/third_party/crashpad/crashpad/util/win/process_info.cc?q=crashpad/util/win/process_info.cc&sq=package:chromium&g=0&l=227 >> https://cs.chromium.org/chromium/src/third_party/crashpad/crashpad/util/win/ntstatus_logging.h?type=cs&q=NTSTATUS_LOG&sq=package:chromium&g=0&l=63 >> >> >> On Fri, Jan 4, 2019 at 12:01 PM Aaron Ballman via cfe-commits >> <cfe-commits@lists.llvm.org> wrote: >>> >>> Author: aaronballman >>> Date: Fri Jan 4 08:58:14 2019 >>> New Revision: 350404 >>> >>> URL: http://llvm.org/viewvc/llvm-project?rev=350404&view=rev >>> Log: >>> Refactor the way we handle diagnosing unused expression results. >>> >>> Rather than sprinkle calls to DiagnoseUnusedExprResult() around in places >>> where we want diagnostics, we now diagnose unused expression statements and >>> full expressions in a more generic way when acting on the final expression >>> statement. This results in more appropriate diagnostics for [[nodiscard]] >>> where we were previously lacking them, such as when the body of a for loop >>> is not a compound statement. >>> >>> This patch fixes PR39837. >>> >>> Modified: >>> cfe/trunk/include/clang/Parse/Parser.h >>> cfe/trunk/include/clang/Sema/Sema.h >>> cfe/trunk/lib/Parse/ParseObjc.cpp >>> cfe/trunk/lib/Parse/ParseOpenMP.cpp >>> cfe/trunk/lib/Parse/ParseStmt.cpp >>> cfe/trunk/lib/Sema/SemaCoroutine.cpp >>> cfe/trunk/lib/Sema/SemaDecl.cpp >>> cfe/trunk/lib/Sema/SemaDeclCXX.cpp >>> cfe/trunk/lib/Sema/SemaExpr.cpp >>> cfe/trunk/lib/Sema/SemaExprCXX.cpp >>> cfe/trunk/lib/Sema/SemaLambda.cpp >>> cfe/trunk/lib/Sema/SemaOpenMP.cpp >>> cfe/trunk/lib/Sema/SemaStmt.cpp >>> cfe/trunk/lib/Sema/TreeTransform.h >>> cfe/trunk/test/CXX/stmt.stmt/stmt.select/p3.cpp >>> cfe/trunk/test/CodeCompletion/pragma-macro-token-caching.c >>> cfe/trunk/test/Parser/cxx1z-init-statement.cpp >>> cfe/trunk/test/Parser/switch-recovery.cpp >>> cfe/trunk/test/SemaCXX/cxx1z-init-statement.cpp >>> cfe/trunk/test/SemaCXX/for-range-examples.cpp >>> cfe/trunk/test/SemaCXX/warn-unused-result.cpp >>> >>> Modified: cfe/trunk/include/clang/Parse/Parser.h >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Parse/Parser.h?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/include/clang/Parse/Parser.h (original) >>> +++ cfe/trunk/include/clang/Parse/Parser.h Fri Jan 4 08:58:14 2019 >>> @@ -360,6 +360,11 @@ class Parser : public CodeCompletionHand >>> /// just a regular sub-expression. >>> SourceLocation ExprStatementTokLoc; >>> >>> + /// Tests whether an expression value is discarded based on token >>> lookahead. >>> + /// It will return true if the lexer is currently processing the }) >>> + /// terminating a GNU statement expression and false otherwise. >>> + bool isExprValueDiscarded(); >>> + >>> public: >>> Parser(Preprocessor &PP, Sema &Actions, bool SkipFunctionBodies); >>> ~Parser() override; >>> >>> Modified: cfe/trunk/include/clang/Sema/Sema.h >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Sema.h?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/include/clang/Sema/Sema.h (original) >>> +++ cfe/trunk/include/clang/Sema/Sema.h Fri Jan 4 08:58:14 2019 >>> @@ -1365,6 +1365,7 @@ public: >>> void PopCompoundScope(); >>> >>> sema::CompoundScopeInfo &getCurCompoundScope() const; >>> + bool isCurCompoundStmtAStmtExpr() const; >>> >>> bool hasAnyUnrecoverableErrorsInThisFunction() const; >>> >>> @@ -3685,16 +3686,17 @@ public: >>> return MakeFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation()); >>> } >>> FullExprArg MakeFullExpr(Expr *Arg, SourceLocation CC) { >>> - return FullExprArg(ActOnFinishFullExpr(Arg, CC).get()); >>> + return FullExprArg( >>> + ActOnFinishFullExpr(Arg, CC, /*DiscardedValue*/ false).get()); >>> } >>> FullExprArg MakeFullDiscardedValueExpr(Expr *Arg) { >>> ExprResult FE = >>> - ActOnFinishFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation(), >>> - /*DiscardedValue*/ true); >>> + ActOnFinishFullExpr(Arg, Arg ? Arg->getExprLoc() : >>> SourceLocation(), >>> + /*DiscardedValue*/ true); >>> return FullExprArg(FE.get()); >>> } >>> >>> - StmtResult ActOnExprStmt(ExprResult Arg); >>> + StmtResult ActOnExprStmt(ExprResult Arg, bool DiscardedValue = true); >>> StmtResult ActOnExprStmtError(); >>> >>> StmtResult ActOnNullStmt(SourceLocation SemiLoc, >>> @@ -5340,13 +5342,12 @@ public: >>> CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary, >>> bool BoundToLvalueReference); >>> >>> - ExprResult ActOnFinishFullExpr(Expr *Expr) { >>> - return ActOnFinishFullExpr(Expr, Expr ? Expr->getExprLoc() >>> - : SourceLocation()); >>> + ExprResult ActOnFinishFullExpr(Expr *Expr, bool DiscardedValue) { >>> + return ActOnFinishFullExpr( >>> + Expr, Expr ? Expr->getExprLoc() : SourceLocation(), >>> DiscardedValue); >>> } >>> ExprResult ActOnFinishFullExpr(Expr *Expr, SourceLocation CC, >>> - bool DiscardedValue = false, >>> - bool IsConstexpr = false); >>> + bool DiscardedValue, bool IsConstexpr = >>> false); >>> StmtResult ActOnFinishFullStmt(Stmt *Stmt); >>> >>> // Marks SS invalid if it represents an incomplete type. >>> >>> Modified: cfe/trunk/lib/Parse/ParseObjc.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseObjc.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Parse/ParseObjc.cpp (original) >>> +++ cfe/trunk/lib/Parse/ParseObjc.cpp Fri Jan 4 08:58:14 2019 >>> @@ -2741,7 +2741,7 @@ StmtResult Parser::ParseObjCAtStatement( >>> >>> // Otherwise, eat the semicolon. >>> ExpectAndConsumeSemi(diag::err_expected_semi_after_expr); >>> - return Actions.ActOnExprStmt(Res); >>> + return Actions.ActOnExprStmt(Res, isExprValueDiscarded()); >>> } >>> >>> ExprResult Parser::ParseObjCAtExpression(SourceLocation AtLoc) { >>> >>> Modified: cfe/trunk/lib/Parse/ParseOpenMP.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseOpenMP.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Parse/ParseOpenMP.cpp (original) >>> +++ cfe/trunk/lib/Parse/ParseOpenMP.cpp Fri Jan 4 08:58:14 2019 >>> @@ -314,7 +314,7 @@ Parser::ParseOpenMPDeclareReductionDirec >>> Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D); >>> ExprResult CombinerResult = >>> Actions.ActOnFinishFullExpr(ParseAssignmentExpression().get(), >>> - D->getLocation(), >>> /*DiscardedValue=*/true); >>> + D->getLocation(), /*DiscardedValue*/ >>> false); >>> Actions.ActOnOpenMPDeclareReductionCombinerEnd(D, >>> CombinerResult.get()); >>> >>> if (CombinerResult.isInvalid() && Tok.isNot(tok::r_paren) && >>> @@ -356,7 +356,7 @@ Parser::ParseOpenMPDeclareReductionDirec >>> if (Actions.getLangOpts().CPlusPlus) { >>> InitializerResult = Actions.ActOnFinishFullExpr( >>> ParseAssignmentExpression().get(), D->getLocation(), >>> - /*DiscardedValue=*/true); >>> + /*DiscardedValue*/ false); >>> } else { >>> ConsumeToken(); >>> ParseOpenMPReductionInitializerForDecl(OmpPrivParm); >>> @@ -364,7 +364,7 @@ Parser::ParseOpenMPDeclareReductionDirec >>> } else { >>> InitializerResult = Actions.ActOnFinishFullExpr( >>> ParseAssignmentExpression().get(), D->getLocation(), >>> - /*DiscardedValue=*/true); >>> + /*DiscardedValue*/ false); >>> } >>> Actions.ActOnOpenMPDeclareReductionInitializerEnd( >>> D, InitializerResult.get(), OmpPrivParm); >>> @@ -1455,7 +1455,7 @@ ExprResult Parser::ParseOpenMPParensExpr >>> ExprResult LHS(ParseCastExpression( >>> /*isUnaryExpression=*/false, /*isAddressOfOperand=*/false, >>> NotTypeCast)); >>> ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional)); >>> - Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc); >>> + Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ >>> false); >>> >>> // Parse ')'. >>> RLoc = Tok.getLocation(); >>> @@ -1711,7 +1711,8 @@ OMPClause *Parser::ParseOpenMPSingleExpr >>> SourceLocation ELoc = Tok.getLocation(); >>> ExprResult LHS(ParseCastExpression(false, false, NotTypeCast)); >>> Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional); >>> - Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc); >>> + Val = >>> + Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ >>> false); >>> } >>> >>> // Parse ')'. >>> @@ -1996,7 +1997,8 @@ bool Parser::ParseOpenMPVarList(OpenMPDi >>> Data.ColonLoc = Tok.getLocation(); >>> SourceLocation ELoc = ConsumeToken(); >>> ExprResult Tail = ParseAssignmentExpression(); >>> - Tail = Actions.ActOnFinishFullExpr(Tail.get(), ELoc); >>> + Tail = >>> + Actions.ActOnFinishFullExpr(Tail.get(), ELoc, /*DiscardedValue*/ >>> false); >>> if (Tail.isUsable()) >>> Data.TailExpr = Tail.get(); >>> else >>> >>> Modified: cfe/trunk/lib/Parse/ParseStmt.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseStmt.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Parse/ParseStmt.cpp (original) >>> +++ cfe/trunk/lib/Parse/ParseStmt.cpp Fri Jan 4 08:58:14 2019 >>> @@ -439,7 +439,7 @@ StmtResult Parser::ParseExprStatement() >>> >>> // Otherwise, eat the semicolon. >>> ExpectAndConsumeSemi(diag::err_expected_semi_after_expr); >>> - return Actions.ActOnExprStmt(Expr); >>> + return Actions.ActOnExprStmt(Expr, isExprValueDiscarded()); >>> } >>> >>> /// ParseSEHTryBlockCommon >>> @@ -958,6 +958,16 @@ bool Parser::ConsumeNullStmt(StmtVector >>> return true; >>> } >>> >>> +bool Parser::isExprValueDiscarded() { >>> + if (Actions.isCurCompoundStmtAStmtExpr()) { >>> + // Look to see if the next two tokens close the statement expression; >>> + // if so, this expression statement is the last statement in a >>> + // statment expression. >>> + return Tok.isNot(tok::r_brace) || NextToken().isNot(tok::r_paren); >>> + } >>> + return true; >>> +} >>> + >>> /// ParseCompoundStatementBody - Parse a sequence of statements and invoke >>> the >>> /// ActOnCompoundStmt action. This expects the '{' to be the current >>> token, and >>> /// consume the '}' at the end of the block. It does not manipulate the >>> scope >>> @@ -1062,7 +1072,7 @@ StmtResult Parser::ParseCompoundStatemen >>> // Eat the semicolon at the end of stmt and convert the expr into a >>> // statement. >>> ExpectAndConsumeSemi(diag::err_expected_semi_after_expr); >>> - R = Actions.ActOnExprStmt(Res); >>> + R = Actions.ActOnExprStmt(Res, isExprValueDiscarded()); >>> } >>> } >>> >>> @@ -1698,8 +1708,16 @@ StmtResult Parser::ParseForStatement(Sou >>> if (!Value.isInvalid()) { >>> if (ForEach) >>> FirstPart = Actions.ActOnForEachLValueExpr(Value.get()); >>> - else >>> - FirstPart = Actions.ActOnExprStmt(Value); >>> + else { >>> + // We already know this is not an init-statement within a for >>> loop, so >>> + // if we are parsing a C++11 range-based for loop, we should treat >>> this >>> + // expression statement as being a discarded value expression >>> because >>> + // we will err below. This way we do not warn on an unused >>> expression >>> + // that was an error in the first place, like with: for (expr : >>> expr); >>> + bool IsRangeBasedFor = >>> + getLangOpts().CPlusPlus11 && !ForEach && Tok.is(tok::colon); >>> + FirstPart = Actions.ActOnExprStmt(Value, !IsRangeBasedFor); >>> + } >>> } >>> >>> if (Tok.is(tok::semi)) { >>> >>> Modified: cfe/trunk/lib/Sema/SemaCoroutine.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaCoroutine.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaCoroutine.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaCoroutine.cpp Fri Jan 4 08:58:14 2019 >>> @@ -647,7 +647,7 @@ bool Sema::ActOnCoroutineBodyStart(Scope >>> return StmtError(); >>> Suspend = BuildResolvedCoawaitExpr(Loc, Suspend.get(), >>> /*IsImplicit*/ true); >>> - Suspend = ActOnFinishFullExpr(Suspend.get()); >>> + Suspend = ActOnFinishFullExpr(Suspend.get(), /*DiscardedValue*/ false); >>> if (Suspend.isInvalid()) { >>> Diag(Loc, diag::note_coroutine_promise_suspend_implicitly_required) >>> << ((Name == "initial_suspend") ? 0 : 1); >>> @@ -868,7 +868,7 @@ StmtResult Sema::BuildCoreturnStmt(Sourc >>> if (PC.isInvalid()) >>> return StmtError(); >>> >>> - Expr *PCE = ActOnFinishFullExpr(PC.get()).get(); >>> + Expr *PCE = ActOnFinishFullExpr(PC.get(), /*DiscardedValue*/ >>> false).get(); >>> >>> Stmt *Res = new (Context) CoreturnStmt(Loc, E, PCE, IsImplicit); >>> return Res; >>> @@ -1237,7 +1237,7 @@ bool CoroutineStmtBuilder::makeNewAndDel >>> >>> ExprResult NewExpr = >>> S.ActOnCallExpr(S.getCurScope(), NewRef.get(), Loc, NewArgs, Loc); >>> - NewExpr = S.ActOnFinishFullExpr(NewExpr.get()); >>> + NewExpr = S.ActOnFinishFullExpr(NewExpr.get(), /*DiscardedValue*/ false); >>> if (NewExpr.isInvalid()) >>> return false; >>> >>> @@ -1263,7 +1263,8 @@ bool CoroutineStmtBuilder::makeNewAndDel >>> >>> ExprResult DeleteExpr = >>> S.ActOnCallExpr(S.getCurScope(), DeleteRef.get(), Loc, DeleteArgs, >>> Loc); >>> - DeleteExpr = S.ActOnFinishFullExpr(DeleteExpr.get()); >>> + DeleteExpr = >>> + S.ActOnFinishFullExpr(DeleteExpr.get(), /*DiscardedValue*/ false); >>> if (DeleteExpr.isInvalid()) >>> return false; >>> >>> @@ -1348,7 +1349,8 @@ bool CoroutineStmtBuilder::makeOnExcepti >>> >>> ExprResult UnhandledException = buildPromiseCall(S, Fn.CoroutinePromise, >>> Loc, >>> "unhandled_exception", >>> None); >>> - UnhandledException = S.ActOnFinishFullExpr(UnhandledException.get(), >>> Loc); >>> + UnhandledException = S.ActOnFinishFullExpr(UnhandledException.get(), Loc, >>> + /*DiscardedValue*/ false); >>> if (UnhandledException.isInvalid()) >>> return false; >>> >>> @@ -1401,7 +1403,8 @@ bool CoroutineStmtBuilder::makeGroDeclAn >>> "get_return_object type must no longer be dependent"); >>> >>> if (FnRetType->isVoidType()) { >>> - ExprResult Res = S.ActOnFinishFullExpr(this->ReturnValue, Loc); >>> + ExprResult Res = >>> + S.ActOnFinishFullExpr(this->ReturnValue, Loc, /*DiscardedValue*/ >>> false); >>> if (Res.isInvalid()) >>> return false; >>> >>> @@ -1433,7 +1436,7 @@ bool CoroutineStmtBuilder::makeGroDeclAn >>> if (Res.isInvalid()) >>> return false; >>> >>> - Res = S.ActOnFinishFullExpr(Res.get()); >>> + Res = S.ActOnFinishFullExpr(Res.get(), /*DiscardedValue*/ false); >>> if (Res.isInvalid()) >>> return false; >>> >>> >>> Modified: cfe/trunk/lib/Sema/SemaDecl.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaDecl.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaDecl.cpp Fri Jan 4 08:58:14 2019 >>> @@ -11204,9 +11204,9 @@ void Sema::AddInitializerToDecl(Decl *Re >>> // struct T { S a, b; } t = { Temp(), Temp() } >>> // >>> // we should destroy the first Temp before constructing the second. >>> - ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(), >>> - false, >>> - VDecl->isConstexpr()); >>> + ExprResult Result = >>> + ActOnFinishFullExpr(Init, VDecl->getLocation(), >>> + /*DiscardedValue*/ false, VDecl->isConstexpr()); >>> if (Result.isInvalid()) { >>> VDecl->setInvalidDecl(); >>> return; >>> >>> Modified: cfe/trunk/lib/Sema/SemaDeclCXX.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDeclCXX.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaDeclCXX.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaDeclCXX.cpp Fri Jan 4 08:58:14 2019 >>> @@ -1205,7 +1205,7 @@ static bool checkTupleLikeDecomposition( >>> E = Seq.Perform(S, Entity, Kind, Init); >>> if (E.isInvalid()) >>> return true; >>> - E = S.ActOnFinishFullExpr(E.get(), Loc); >>> + E = S.ActOnFinishFullExpr(E.get(), Loc, /*DiscardedValue*/ false); >>> if (E.isInvalid()) >>> return true; >>> RefVD->setInit(E.get()); >>> @@ -3682,7 +3682,7 @@ void Sema::ActOnFinishCXXInClassMemberIn >>> // C++11 [class.base.init]p7: >>> // The initialization of each base and member constitutes a >>> // full-expression. >>> - Init = ActOnFinishFullExpr(Init.get(), InitLoc); >>> + Init = ActOnFinishFullExpr(Init.get(), InitLoc, /*DiscardedValue*/ >>> false); >>> if (Init.isInvalid()) { >>> FD->setInvalidDecl(); >>> return; >>> @@ -4040,7 +4040,8 @@ Sema::BuildMemberInitializer(ValueDecl * >>> // C++11 [class.base.init]p7: >>> // The initialization of each base and member constitutes a >>> // full-expression. >>> - MemberInit = ActOnFinishFullExpr(MemberInit.get(), >>> InitRange.getBegin()); >>> + MemberInit = ActOnFinishFullExpr(MemberInit.get(), >>> InitRange.getBegin(), >>> + /*DiscardedValue*/ false); >>> if (MemberInit.isInvalid()) >>> return true; >>> >>> @@ -4095,8 +4096,8 @@ Sema::BuildDelegatingInitializer(TypeSou >>> // C++11 [class.base.init]p7: >>> // The initialization of each base and member constitutes a >>> // full-expression. >>> - DelegationInit = ActOnFinishFullExpr(DelegationInit.get(), >>> - InitRange.getBegin()); >>> + DelegationInit = ActOnFinishFullExpr( >>> + DelegationInit.get(), InitRange.getBegin(), /*DiscardedValue*/ >>> false); >>> if (DelegationInit.isInvalid()) >>> return true; >>> >>> @@ -4225,7 +4226,8 @@ Sema::BuildBaseInitializer(QualType Base >>> // C++11 [class.base.init]p7: >>> // The initialization of each base and member constitutes a >>> // full-expression. >>> - BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin()); >>> + BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin(), >>> + /*DiscardedValue*/ false); >>> if (BaseInit.isInvalid()) >>> return true; >>> >>> >>> Modified: cfe/trunk/lib/Sema/SemaExpr.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExpr.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaExpr.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaExpr.cpp Fri Jan 4 08:58:14 2019 >>> @@ -4736,8 +4736,9 @@ bool Sema::CheckCXXDefaultArgExpr(Source >>> if (Result.isInvalid()) >>> return true; >>> >>> - Result = ActOnFinishFullExpr(Result.getAs<Expr>(), >>> - Param->getOuterLocStart()); >>> + Result = >>> + ActOnFinishFullExpr(Result.getAs<Expr>(), >>> Param->getOuterLocStart(), >>> + /*DiscardedValue*/ false); >>> if (Result.isInvalid()) >>> return true; >>> >>> >>> Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprCXX.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaExprCXX.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaExprCXX.cpp Fri Jan 4 08:58:14 2019 >>> @@ -7803,6 +7803,8 @@ ExprResult Sema::ActOnFinishFullExpr(Exp >>> FullExpr = IgnoredValueConversions(FullExpr.get()); >>> if (FullExpr.isInvalid()) >>> return ExprError(); >>> + >>> + DiagnoseUnusedExprResult(FullExpr.get()); >>> } >>> >>> FullExpr = CorrectDelayedTyposInExpr(FullExpr.get()); >>> >>> Modified: cfe/trunk/lib/Sema/SemaLambda.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaLambda.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaLambda.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaLambda.cpp Fri Jan 4 08:58:14 2019 >>> @@ -1724,7 +1724,7 @@ ExprResult Sema::BuildBlockForLambdaConv >>> /*NRVO=*/false), >>> CurrentLocation, Src); >>> if (!Init.isInvalid()) >>> - Init = ActOnFinishFullExpr(Init.get()); >>> + Init = ActOnFinishFullExpr(Init.get(), /*DiscardedValue*/ false); >>> >>> if (Init.isInvalid()) >>> return ExprError(); >>> >>> Modified: cfe/trunk/lib/Sema/SemaOpenMP.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaOpenMP.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaOpenMP.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaOpenMP.cpp Fri Jan 4 08:58:14 2019 >>> @@ -5320,7 +5320,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> LastIteration.get(), UB.get()); >>> EUB = SemaRef.BuildBinOp(CurScope, InitLoc, BO_Assign, UB.get(), >>> CondOp.get()); >>> - EUB = SemaRef.ActOnFinishFullExpr(EUB.get()); >>> + EUB = SemaRef.ActOnFinishFullExpr(EUB.get(), /*DiscardedValue*/ false); >>> >>> // If we have a combined directive that combines 'distribute', 'for' or >>> // 'simd' we need to be able to access the bounds of the schedule of >>> the >>> @@ -5349,7 +5349,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> LastIteration.get(), CombUB.get()); >>> CombEUB = SemaRef.BuildBinOp(CurScope, InitLoc, BO_Assign, >>> CombUB.get(), >>> CombCondOp.get()); >>> - CombEUB = SemaRef.ActOnFinishFullExpr(CombEUB.get()); >>> + CombEUB = >>> + SemaRef.ActOnFinishFullExpr(CombEUB.get(), /*DiscardedValue*/ >>> false); >>> >>> const CapturedDecl *CD = >>> cast<CapturedStmt>(AStmt)->getCapturedDecl(); >>> // We expect to have at least 2 more parameters than the 'parallel' >>> @@ -5383,7 +5384,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> ? LB.get() >>> : SemaRef.ActOnIntegerConstant(SourceLocation(), 0).get(); >>> Init = SemaRef.BuildBinOp(CurScope, InitLoc, BO_Assign, IV.get(), RHS); >>> - Init = SemaRef.ActOnFinishFullExpr(Init.get()); >>> + Init = SemaRef.ActOnFinishFullExpr(Init.get(), /*DiscardedValue*/ >>> false); >>> >>> if (isOpenMPLoopBoundSharingDirective(DKind)) { >>> Expr *CombRHS = >>> @@ -5394,7 +5395,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> : SemaRef.ActOnIntegerConstant(SourceLocation(), 0).get(); >>> CombInit = >>> SemaRef.BuildBinOp(CurScope, InitLoc, BO_Assign, IV.get(), >>> CombRHS); >>> - CombInit = SemaRef.ActOnFinishFullExpr(CombInit.get()); >>> + CombInit = >>> + SemaRef.ActOnFinishFullExpr(CombInit.get(), /*DiscardedValue*/ >>> false); >>> } >>> } >>> >>> @@ -5426,7 +5428,7 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> if (!Inc.isUsable()) >>> return 0; >>> Inc = SemaRef.BuildBinOp(CurScope, IncLoc, BO_Assign, IV.get(), >>> Inc.get()); >>> - Inc = SemaRef.ActOnFinishFullExpr(Inc.get()); >>> + Inc = SemaRef.ActOnFinishFullExpr(Inc.get(), /*DiscardedValue*/ false); >>> if (!Inc.isUsable()) >>> return 0; >>> >>> @@ -5444,7 +5446,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> // LB = LB + ST >>> NextLB = >>> SemaRef.BuildBinOp(CurScope, IncLoc, BO_Assign, LB.get(), >>> NextLB.get()); >>> - NextLB = SemaRef.ActOnFinishFullExpr(NextLB.get()); >>> + NextLB = >>> + SemaRef.ActOnFinishFullExpr(NextLB.get(), /*DiscardedValue*/ >>> false); >>> if (!NextLB.isUsable()) >>> return 0; >>> // UB + ST >>> @@ -5454,7 +5457,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> // UB = UB + ST >>> NextUB = >>> SemaRef.BuildBinOp(CurScope, IncLoc, BO_Assign, UB.get(), >>> NextUB.get()); >>> - NextUB = SemaRef.ActOnFinishFullExpr(NextUB.get()); >>> + NextUB = >>> + SemaRef.ActOnFinishFullExpr(NextUB.get(), /*DiscardedValue*/ >>> false); >>> if (!NextUB.isUsable()) >>> return 0; >>> if (isOpenMPLoopBoundSharingDirective(DKind)) { >>> @@ -5465,7 +5469,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> // LB = LB + ST >>> CombNextLB = SemaRef.BuildBinOp(CurScope, IncLoc, BO_Assign, >>> CombLB.get(), >>> CombNextLB.get()); >>> - CombNextLB = SemaRef.ActOnFinishFullExpr(CombNextLB.get()); >>> + CombNextLB = SemaRef.ActOnFinishFullExpr(CombNextLB.get(), >>> + /*DiscardedValue*/ false); >>> if (!CombNextLB.isUsable()) >>> return 0; >>> // UB + ST >>> @@ -5476,7 +5481,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> // UB = UB + ST >>> CombNextUB = SemaRef.BuildBinOp(CurScope, IncLoc, BO_Assign, >>> CombUB.get(), >>> CombNextUB.get()); >>> - CombNextUB = SemaRef.ActOnFinishFullExpr(CombNextUB.get()); >>> + CombNextUB = SemaRef.ActOnFinishFullExpr(CombNextUB.get(), >>> + /*DiscardedValue*/ false); >>> if (!CombNextUB.isUsable()) >>> return 0; >>> } >>> @@ -5497,7 +5503,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> assert(DistInc.isUsable() && "distribute inc expr was not built"); >>> DistInc = SemaRef.BuildBinOp(CurScope, DistIncLoc, BO_Assign, IV.get(), >>> DistInc.get()); >>> - DistInc = SemaRef.ActOnFinishFullExpr(DistInc.get()); >>> + DistInc = >>> + SemaRef.ActOnFinishFullExpr(DistInc.get(), /*DiscardedValue*/ >>> false); >>> assert(DistInc.isUsable() && "distribute inc expr was not built"); >>> >>> // Build expression: UB = min(UB, prevUB) for #for in composite or >>> combined >>> @@ -5509,7 +5516,8 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> DistEUBLoc, DistEUBLoc, IsUBGreater.get(), PrevUB.get(), UB.get()); >>> PrevEUB = SemaRef.BuildBinOp(CurScope, DistIncLoc, BO_Assign, UB.get(), >>> CondOp.get()); >>> - PrevEUB = SemaRef.ActOnFinishFullExpr(PrevEUB.get()); >>> + PrevEUB = >>> + SemaRef.ActOnFinishFullExpr(PrevEUB.get(), /*DiscardedValue*/ >>> false); >>> >>> // Build IV <= PrevUB to be used in parallel for is in combination with >>> // a distribute directive with schedule(static, 1) >>> @@ -5613,8 +5621,10 @@ checkOpenMPLoop(OpenMPDirectiveKind DKin >>> Built.IterationVarRef = IV.get(); >>> Built.LastIteration = LastIteration.get(); >>> Built.NumIterations = NumIterations.get(); >>> - Built.CalcLastIteration = >>> - SemaRef.ActOnFinishFullExpr(CalcLastIteration.get()).get(); >>> + Built.CalcLastIteration = SemaRef >>> + >>> .ActOnFinishFullExpr(CalcLastIteration.get(), >>> + /*DiscardedValue*/ >>> false) >>> + .get(); >>> Built.PreCond = PreCond.get(); >>> Built.PreInits = buildPreInits(C, Captures); >>> Built.Cond = Cond.get(); >>> @@ -10267,8 +10277,8 @@ OMPClause *Sema::ActOnOpenMPLastprivateC >>> PseudoDstExpr, PseudoSrcExpr); >>> if (AssignmentOp.isInvalid()) >>> continue; >>> - AssignmentOp = ActOnFinishFullExpr(AssignmentOp.get(), ELoc, >>> - /*DiscardedValue=*/true); >>> + AssignmentOp = >>> + ActOnFinishFullExpr(AssignmentOp.get(), ELoc, /*DiscardedValue*/ >>> false); >>> if (AssignmentOp.isInvalid()) >>> continue; >>> >>> @@ -11274,7 +11284,8 @@ static bool actOnOMPReductionKindClause( >>> BO_Assign, LHSDRE, ConditionalOp); >>> } >>> if (ReductionOp.isUsable()) >>> - ReductionOp = S.ActOnFinishFullExpr(ReductionOp.get()); >>> + ReductionOp = S.ActOnFinishFullExpr(ReductionOp.get(), >>> + /*DiscardedValue*/ false); >>> } >>> if (!ReductionOp.isUsable()) >>> continue; >>> @@ -11612,7 +11623,7 @@ OMPClause *Sema::ActOnOpenMPLinearClause >>> buildDeclRefExpr(*this, SaveVar, StepExpr->getType(), StepLoc); >>> ExprResult CalcStep = >>> BuildBinOp(CurScope, StepLoc, BO_Assign, SaveRef.get(), StepExpr); >>> - CalcStep = ActOnFinishFullExpr(CalcStep.get()); >>> + CalcStep = ActOnFinishFullExpr(CalcStep.get(), /*DiscardedValue*/ >>> false); >>> >>> // Warn about zero linear step (it would be probably better specified >>> as >>> // making corresponding variables 'const'). >>> @@ -11700,7 +11711,7 @@ static bool FinishOpenMPLinearClause(OMP >>> else >>> Update = *CurPrivate; >>> Update = SemaRef.ActOnFinishFullExpr(Update.get(), DE->getBeginLoc(), >>> - /*DiscardedValue=*/true); >>> + /*DiscardedValue*/ false); >>> >>> // Build final: Var = InitExpr + NumIterations * Step >>> ExprResult Final; >>> @@ -11711,7 +11722,7 @@ static bool FinishOpenMPLinearClause(OMP >>> else >>> Final = *CurPrivate; >>> Final = SemaRef.ActOnFinishFullExpr(Final.get(), DE->getBeginLoc(), >>> - /*DiscardedValue=*/true); >>> + /*DiscardedValue*/ false); >>> >>> if (!Update.isUsable() || !Final.isUsable()) { >>> Updates.push_back(nullptr); >>> @@ -11879,7 +11890,7 @@ OMPClause *Sema::ActOnOpenMPCopyinClause >>> if (AssignmentOp.isInvalid()) >>> continue; >>> AssignmentOp = ActOnFinishFullExpr(AssignmentOp.get(), >>> DE->getExprLoc(), >>> - /*DiscardedValue=*/true); >>> + /*DiscardedValue*/ false); >>> if (AssignmentOp.isInvalid()) >>> continue; >>> >>> @@ -11987,8 +11998,8 @@ OMPClause *Sema::ActOnOpenMPCopyprivateC >>> DSAStack->getCurScope(), ELoc, BO_Assign, PseudoDstExpr, >>> PseudoSrcExpr); >>> if (AssignmentOp.isInvalid()) >>> continue; >>> - AssignmentOp = ActOnFinishFullExpr(AssignmentOp.get(), ELoc, >>> - /*DiscardedValue=*/true); >>> + AssignmentOp = >>> + ActOnFinishFullExpr(AssignmentOp.get(), ELoc, /*DiscardedValue*/ >>> false); >>> if (AssignmentOp.isInvalid()) >>> continue; >>> >>> >>> Modified: cfe/trunk/lib/Sema/SemaStmt.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaStmt.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaStmt.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaStmt.cpp Fri Jan 4 08:58:14 2019 >>> @@ -42,12 +42,11 @@ >>> using namespace clang; >>> using namespace sema; >>> >>> -StmtResult Sema::ActOnExprStmt(ExprResult FE) { >>> +StmtResult Sema::ActOnExprStmt(ExprResult FE, bool DiscardedValue) { >>> if (FE.isInvalid()) >>> return StmtError(); >>> >>> - FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(), >>> - /*DiscardedValue*/ true); >>> + FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(), >>> DiscardedValue); >>> if (FE.isInvalid()) >>> return StmtError(); >>> >>> @@ -348,6 +347,10 @@ sema::CompoundScopeInfo &Sema::getCurCom >>> return getCurFunction()->CompoundScopes.back(); >>> } >>> >>> +bool Sema::isCurCompoundStmtAStmtExpr() const { >>> + return getCurCompoundScope().IsStmtExpr; >>> +} >>> + >>> StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R, >>> ArrayRef<Stmt *> Elts, bool isStmtExpr) >>> { >>> const unsigned NumElts = Elts.size(); >>> @@ -370,14 +373,6 @@ StmtResult Sema::ActOnCompoundStmt(Sourc >>> Diag(D->getLocation(), diag::ext_mixed_decls_code); >>> } >>> } >>> - // Warn about unused expressions in statements. >>> - for (unsigned i = 0; i != NumElts; ++i) { >>> - // Ignore statements that are last in a statement expression. >>> - if (isStmtExpr && i == NumElts - 1) >>> - continue; >>> - >>> - DiagnoseUnusedExprResult(Elts[i]); >>> - } >>> >>> // Check for suspicious empty body (null statement) in `for' and `while' >>> // statements. Don't do anything for template instantiations, this just >>> adds >>> @@ -469,15 +464,12 @@ Sema::ActOnCaseStmt(SourceLocation CaseL >>> >>> /// ActOnCaseStmtBody - This installs a statement as the body of a case. >>> void Sema::ActOnCaseStmtBody(Stmt *S, Stmt *SubStmt) { >>> - DiagnoseUnusedExprResult(SubStmt); >>> cast<CaseStmt>(S)->setSubStmt(SubStmt); >>> } >>> >>> StmtResult >>> Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc, >>> Stmt *SubStmt, Scope *CurScope) { >>> - DiagnoseUnusedExprResult(SubStmt); >>> - >>> if (getCurFunction()->SwitchStack.empty()) { >>> Diag(DefaultLoc, diag::err_default_not_in_switch); >>> return SubStmt; >>> @@ -571,9 +563,6 @@ StmtResult Sema::BuildIfStmt(SourceLocat >>> if (IsConstexpr || isa<ObjCAvailabilityCheckExpr>(Cond.get().second)) >>> setFunctionHasBranchProtectedScope(); >>> >>> - DiagnoseUnusedExprResult(thenStmt); >>> - DiagnoseUnusedExprResult(elseStmt); >>> - >>> return IfStmt::Create(Context, IfLoc, IsConstexpr, InitStmt, >>> Cond.get().first, >>> Cond.get().second, thenStmt, ElseLoc, elseStmt); >>> } >>> @@ -1301,8 +1290,6 @@ StmtResult Sema::ActOnWhileStmt(SourceLo >>> !Diags.isIgnored(diag::warn_comma_operator, >>> CondVal.second->getExprLoc())) >>> CommaVisitor(*this).Visit(CondVal.second); >>> >>> - DiagnoseUnusedExprResult(Body); >>> - >>> if (isa<NullStmt>(Body)) >>> getCurCompoundScope().setHasEmptyLoopBodies(); >>> >>> @@ -1322,7 +1309,7 @@ Sema::ActOnDoStmt(SourceLocation DoLoc, >>> return StmtError(); >>> Cond = CondResult.get(); >>> >>> - CondResult = ActOnFinishFullExpr(Cond, DoLoc); >>> + CondResult = ActOnFinishFullExpr(Cond, DoLoc, /*DiscardedValue*/ false); >>> if (CondResult.isInvalid()) >>> return StmtError(); >>> Cond = CondResult.get(); >>> @@ -1332,8 +1319,6 @@ Sema::ActOnDoStmt(SourceLocation DoLoc, >>> !Diags.isIgnored(diag::warn_comma_operator, Cond->getExprLoc())) >>> CommaVisitor(*this).Visit(Cond); >>> >>> - DiagnoseUnusedExprResult(Body); >>> - >>> return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen); >>> } >>> >>> @@ -1778,11 +1763,6 @@ StmtResult Sema::ActOnForStmt(SourceLoca >>> CommaVisitor(*this).Visit(Second.get().second); >>> >>> Expr *Third = third.release().getAs<Expr>(); >>> - >>> - DiagnoseUnusedExprResult(First); >>> - DiagnoseUnusedExprResult(Third); >>> - DiagnoseUnusedExprResult(Body); >>> - >>> if (isa<NullStmt>(Body)) >>> getCurCompoundScope().setHasEmptyLoopBodies(); >>> >>> @@ -1802,7 +1782,7 @@ StmtResult Sema::ActOnForEachLValueExpr( >>> if (result.isInvalid()) return StmtError(); >>> E = result.get(); >>> >>> - ExprResult FullExpr = ActOnFinishFullExpr(E); >>> + ExprResult FullExpr = ActOnFinishFullExpr(E, /*DiscardedValue*/ false); >>> if (FullExpr.isInvalid()) >>> return StmtError(); >>> return StmtResult(static_cast<Stmt*>(FullExpr.get())); >>> @@ -1956,7 +1936,8 @@ Sema::ActOnObjCForCollectionStmt(SourceL >>> if (CollectionExprResult.isInvalid()) >>> return StmtError(); >>> >>> - CollectionExprResult = ActOnFinishFullExpr(CollectionExprResult.get()); >>> + CollectionExprResult = >>> + ActOnFinishFullExpr(CollectionExprResult.get(), /*DiscardedValue*/ >>> false); >>> if (CollectionExprResult.isInvalid()) >>> return StmtError(); >>> >>> @@ -2593,7 +2574,8 @@ StmtResult Sema::BuildCXXForRangeStmt(So >>> if (!NotEqExpr.isInvalid()) >>> NotEqExpr = CheckBooleanCondition(ColonLoc, NotEqExpr.get()); >>> if (!NotEqExpr.isInvalid()) >>> - NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get()); >>> + NotEqExpr = >>> + ActOnFinishFullExpr(NotEqExpr.get(), /*DiscardedValue*/ false); >>> if (NotEqExpr.isInvalid()) { >>> Diag(RangeLoc, diag::note_for_range_invalid_iterator) >>> << RangeLoc << 0 << BeginRangeRef.get()->getType(); >>> @@ -2616,7 +2598,7 @@ StmtResult Sema::BuildCXXForRangeStmt(So >>> // co_await during the initial parse. >>> IncrExpr = ActOnCoawaitExpr(S, CoawaitLoc, IncrExpr.get()); >>> if (!IncrExpr.isInvalid()) >>> - IncrExpr = ActOnFinishFullExpr(IncrExpr.get()); >>> + IncrExpr = ActOnFinishFullExpr(IncrExpr.get(), /*DiscardedValue*/ >>> false); >>> if (IncrExpr.isInvalid()) { >>> Diag(RangeLoc, diag::note_for_range_invalid_iterator) >>> << RangeLoc << 2 << BeginRangeRef.get()->getType() ; >>> @@ -2871,7 +2853,7 @@ Sema::ActOnIndirectGotoStmt(SourceLocati >>> return StmtError(); >>> } >>> >>> - ExprResult ExprRes = ActOnFinishFullExpr(E); >>> + ExprResult ExprRes = ActOnFinishFullExpr(E, /*DiscardedValue*/ false); >>> if (ExprRes.isInvalid()) >>> return StmtError(); >>> E = ExprRes.get(); >>> @@ -3221,7 +3203,8 @@ Sema::ActOnCapScopeReturnStmt(SourceLoca >>> ExpressionEvaluationContext::DiscardedStatement && >>> (HasDeducedReturnType || CurCap->HasImplicitReturnType)) { >>> if (RetValExp) { >>> - ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); >>> + ExprResult ER = >>> + ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ >>> false); >>> if (ER.isInvalid()) >>> return StmtError(); >>> RetValExp = ER.get(); >>> @@ -3348,7 +3331,8 @@ Sema::ActOnCapScopeReturnStmt(SourceLoca >>> } >>> >>> if (RetValExp) { >>> - ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); >>> + ExprResult ER = >>> + ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ >>> false); >>> if (ER.isInvalid()) >>> return StmtError(); >>> RetValExp = ER.get(); >>> @@ -3578,7 +3562,8 @@ StmtResult Sema::BuildReturnStmt(SourceL >>> ExpressionEvaluationContext::DiscardedStatement && >>> FnRetType->getContainedAutoType()) { >>> if (RetValExp) { >>> - ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); >>> + ExprResult ER = >>> + ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ >>> false); >>> if (ER.isInvalid()) >>> return StmtError(); >>> RetValExp = ER.get(); >>> @@ -3672,7 +3657,8 @@ StmtResult Sema::BuildReturnStmt(SourceL >>> } >>> >>> if (RetValExp) { >>> - ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); >>> + ExprResult ER = >>> + ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ >>> false); >>> if (ER.isInvalid()) >>> return StmtError(); >>> RetValExp = ER.get(); >>> @@ -3751,7 +3737,8 @@ StmtResult Sema::BuildReturnStmt(SourceL >>> } >>> >>> if (RetValExp) { >>> - ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); >>> + ExprResult ER = >>> + ActOnFinishFullExpr(RetValExp, ReturnLoc, /*DiscardedValue*/ >>> false); >>> if (ER.isInvalid()) >>> return StmtError(); >>> RetValExp = ER.get(); >>> @@ -3804,7 +3791,7 @@ StmtResult Sema::BuildObjCAtThrowStmt(So >>> if (Result.isInvalid()) >>> return StmtError(); >>> >>> - Result = ActOnFinishFullExpr(Result.get()); >>> + Result = ActOnFinishFullExpr(Result.get(), /*DiscardedValue*/ false); >>> if (Result.isInvalid()) >>> return StmtError(); >>> Throw = Result.get(); >>> @@ -3876,7 +3863,7 @@ Sema::ActOnObjCAtSynchronizedOperand(Sou >>> } >>> >>> // The operand to @synchronized is a full-expression. >>> - return ActOnFinishFullExpr(operand); >>> + return ActOnFinishFullExpr(operand, /*DiscardedValue*/ false); >>> } >>> >>> StmtResult >>> >>> Modified: cfe/trunk/lib/Sema/TreeTransform.h >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/TreeTransform.h?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/TreeTransform.h (original) >>> +++ cfe/trunk/lib/Sema/TreeTransform.h Fri Jan 4 08:58:14 2019 >>> @@ -328,7 +328,7 @@ public: >>> /// other mechanism. >>> /// >>> /// \returns the transformed statement. >>> - StmtResult TransformStmt(Stmt *S); >>> + StmtResult TransformStmt(Stmt *S, bool DiscardedValue = false); >>> >>> /// Transform the given statement. >>> /// >>> @@ -3269,8 +3269,8 @@ private: >>> bool DeducibleTSTContext); >>> }; >>> >>> -template<typename Derived> >>> -StmtResult TreeTransform<Derived>::TransformStmt(Stmt *S) { >>> +template <typename Derived> >>> +StmtResult TreeTransform<Derived>::TransformStmt(Stmt *S, bool >>> DiscardedValue) { >>> if (!S) >>> return S; >>> >>> @@ -3294,7 +3294,7 @@ StmtResult TreeTransform<Derived>::Trans >>> if (E.isInvalid()) >>> return StmtError(); >>> >>> - return getSema().ActOnExprStmt(E); >>> + return getSema().ActOnExprStmt(E, DiscardedValue); >>> } >>> } >>> >>> @@ -4715,7 +4715,8 @@ TreeTransform<Derived>::TransformVariabl >>> } >>> if (SizeResult.isInvalid()) >>> return QualType(); >>> - SizeResult = SemaRef.ActOnFinishFullExpr(SizeResult.get()); >>> + SizeResult = >>> + SemaRef.ActOnFinishFullExpr(SizeResult.get(), /*DiscardedValue*/ >>> false); >>> if (SizeResult.isInvalid()) >>> return QualType(); >>> >>> @@ -6520,7 +6521,9 @@ TreeTransform<Derived>::TransformCompoun >>> bool SubStmtChanged = false; >>> SmallVector<Stmt*, 8> Statements; >>> for (auto *B : S->body()) { >>> - StmtResult Result = getDerived().TransformStmt(B); >>> + StmtResult Result = >>> + getDerived().TransformStmt(B, !IsStmtExpr || B != S->body_back()); >>> + >>> if (Result.isInvalid()) { >>> // Immediately fail if this was a DeclStmt, since it's very >>> // likely that this will cause problems for future statements. >>> >>> Modified: cfe/trunk/test/CXX/stmt.stmt/stmt.select/p3.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CXX/stmt.stmt/stmt.select/p3.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/CXX/stmt.stmt/stmt.select/p3.cpp (original) >>> +++ cfe/trunk/test/CXX/stmt.stmt/stmt.select/p3.cpp Fri Jan 4 08:58:14 2019 >>> @@ -1,5 +1,5 @@ >>> -// RUN: %clang_cc1 -fsyntax-only -verify %s >>> -// RUN: %clang_cc1 -fsyntax-only -std=c++1z -Wc++14-compat -verify %s >>> -DCPP17 >>> +// RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify %s >>> +// RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -std=c++1z >>> -Wc++14-compat -verify %s -DCPP17 >>> >>> int f(); >>> >>> @@ -71,7 +71,6 @@ void whileInitStatement() { >>> // last loop above. It would be nice to remove this. >>> void whileInitStatement2() { >>> while (; false) {} // expected-error {{expected expression}} >>> - // expected-warning@-1 {{expression result unused}} >>> - // expected-error@-2 {{expected ';' after expression}} >>> - // expected-error@-3 {{expected expression}} >>> + // expected-error@-1 {{expected ';' after expression}} >>> + // expected-error@-2 {{expected expression}} >>> } >>> >>> Modified: cfe/trunk/test/CodeCompletion/pragma-macro-token-caching.c >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeCompletion/pragma-macro-token-caching.c?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/CodeCompletion/pragma-macro-token-caching.c (original) >>> +++ cfe/trunk/test/CodeCompletion/pragma-macro-token-caching.c Fri Jan 4 >>> 08:58:14 2019 >>> @@ -12,7 +12,7 @@ void completeParam(int param) { >>> >>> void completeParamPragmaError(int param) { >>> Outer(__extension__({ _Pragma(2) })); // expected-error {{_Pragma >>> takes a parenthesized string literal}} >>> - param; >>> + param; // expected-warning {{expression result unused}} >>> } >>> >>> // RUN: %clang_cc1 -fsyntax-only -verify -code-completion-at=%s:16:1 %s | >>> FileCheck %s >>> >>> Modified: cfe/trunk/test/Parser/cxx1z-init-statement.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Parser/cxx1z-init-statement.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/Parser/cxx1z-init-statement.cpp (original) >>> +++ cfe/trunk/test/Parser/cxx1z-init-statement.cpp Fri Jan 4 08:58:14 2019 >>> @@ -13,9 +13,9 @@ int f() { >>> if (T(n) = 0; n) {} >>> >>> // init-statement expressions >>> - if (T{f()}; f()) {} >>> - if (T{f()}, g, h; f()) {} // expected-warning 2{{unused}} >>> - if (T(f()), g, h + 1; f()) {} // expected-warning 2{{unused}} >>> + if (T{f()}; f()) {} // expected-warning {{expression result unused}} >>> + if (T{f()}, g, h; f()) {} // expected-warning 2{{unused}} >>> expected-warning {{expression result unused}} >>> + if (T(f()), g, h + 1; f()) {} // expected-warning 2{{unused}} >>> expected-warning {{expression result unused}} >>> >>> // condition declarations >>> if (T(n){g}) {} >>> @@ -35,7 +35,7 @@ int f() { >>> >>> // Likewise for 'switch' >>> switch (int n; n) {} >>> - switch (g; int g = 5) {} >>> + switch (g; int g = 5) {} // expected-warning {{expression result unused}} >>> >>> if (int a, b; int c = a) { // expected-note 6{{previous}} >>> int a; // expected-error {{redefinition}} >>> >>> Modified: cfe/trunk/test/Parser/switch-recovery.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Parser/switch-recovery.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/Parser/switch-recovery.cpp (original) >>> +++ cfe/trunk/test/Parser/switch-recovery.cpp Fri Jan 4 08:58:14 2019 >>> @@ -105,7 +105,7 @@ void test9(int x) { // expected-note {{' >>> expected-error {{expected expression}} >>> 8:: x; // expected-error {{expected ';' after expression}} \ >>> expected-error {{no member named 'x' in the global >>> namespace; did you mean simply 'x'?}} \ >>> - expected-warning 2 {{expression result unused}} >>> + expected-warning {{expression result unused}} >>> 9:: :y; // expected-error {{expected ';' after expression}} \ >>> expected-error {{expected unqualified-id}} \ >>> expected-warning {{expression result unused}} >>> >>> Modified: cfe/trunk/test/SemaCXX/cxx1z-init-statement.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/cxx1z-init-statement.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/cxx1z-init-statement.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/cxx1z-init-statement.cpp Fri Jan 4 08:58:14 2019 >>> @@ -1,5 +1,5 @@ >>> -// RUN: %clang_cc1 -std=c++1z -verify %s >>> -// RUN: %clang_cc1 -std=c++17 -verify %s >>> +// RUN: %clang_cc1 -std=c++1z -Wno-unused-value -verify %s >>> +// RUN: %clang_cc1 -std=c++17 -Wno-unused-value -verify %s >>> >>> void testIf() { >>> int x = 0; >>> @@ -12,7 +12,7 @@ void testIf() { >>> int x = 0; // expected-error {{redefinition of 'x'}} >>> >>> if (x; int a = 0) ++a; >>> - if (x, +x; int a = 0) // expected-note 2 {{previous definition is here}} >>> expected-warning {{unused}} >>> + if (x, +x; int a = 0) // expected-note 2 {{previous definition is here}} >>> int a = 0; // expected-error {{redefinition of 'a'}} >>> else >>> int a = 0; // expected-error {{redefinition of 'a'}} >>> @@ -48,7 +48,7 @@ void testSwitch() { >>> ++a; >>> } >>> >>> - switch (x, +x; int a = 0) { // expected-note {{previous definition is >>> here}} expected-warning {{unused}} >>> + switch (x, +x; int a = 0) { // expected-note {{previous definition is >>> here}} >>> case 0: >>> int a = 0; // expected-error {{redefinition of 'a'}} // >>> expected-note {{previous definition is here}} >>> case 1: >>> >>> Modified: cfe/trunk/test/SemaCXX/for-range-examples.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/for-range-examples.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/for-range-examples.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/for-range-examples.cpp Fri Jan 4 08:58:14 2019 >>> @@ -244,7 +244,7 @@ void foo () >>> { >>> int b = 1, a[b]; >>> a[0] = 0; >>> - [&] { for (int c : a) 0; } (); >>> + [&] { for (int c : a) 0; } (); // expected-warning {{expression result >>> unused}} >>> } >>> >>> >>> >>> Modified: cfe/trunk/test/SemaCXX/warn-unused-result.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-unused-result.cpp?rev=350404&r1=350403&r2=350404&view=diff >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/warn-unused-result.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/warn-unused-result.cpp Fri Jan 4 08:58:14 2019 >>> @@ -33,6 +33,36 @@ void test() { >>> const S &s4 = g1(); >>> } >>> >>> +void testSubstmts(int i) { >>> + switch (i) { >>> + case 0: >>> + f(); // expected-warning {{ignoring return value}} >>> + default: >>> + f(); // expected-warning {{ignoring return value}} >>> + } >>> + >>> + if (i) >>> + f(); // expected-warning {{ignoring return value}} >>> + else >>> + f(); // expected-warning {{ignoring return value}} >>> + >>> + while (i) >>> + f(); // expected-warning {{ignoring return value}} >>> + >>> + do >>> + f(); // expected-warning {{ignoring return value}} >>> + while (i); >>> + >>> + for (f(); // expected-warning {{ignoring return value}} >>> + ; >>> + f() // expected-warning {{ignoring return value}} >>> + ) >>> + f(); // expected-warning {{ignoring return value}} >>> + >>> + f(), // expected-warning {{ignoring return value}} >>> + (void)f(); >>> +} >>> + >>> struct X { >>> int foo() __attribute__((warn_unused_result)); >>> }; >>> @@ -206,3 +236,13 @@ void f() { >>> (void)++p; >>> } >>> } // namespace >>> + >>> +namespace PR39837 { >>> +[[clang::warn_unused_result]] int f(int); >>> + >>> +void g() { >>> + int a[2]; >>> + for (int b : a) >>> + f(b); // expected-warning {{ignoring return value}} >>> +} >>> +} // namespace PR39837 >>> >>> >>> _______________________________________________ >>> cfe-commits mailing list >>> cfe-commits@lists.llvm.org >>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits >> >> _______________________________________________ >> cfe-commits mailing list >> cfe-commits@lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
