forked from OSchip/llvm-project
4078 lines
150 KiB
C++
4078 lines
150 KiB
C++
//===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements semantic analysis for statements.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Sema/SemaInternal.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/AST/ASTDiagnostic.h"
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#include "clang/AST/CharUnits.h"
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#include "clang/AST/CXXInheritance.h"
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#include "clang/AST/DeclObjC.h"
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#include "clang/AST/EvaluatedExprVisitor.h"
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#include "clang/AST/ExprCXX.h"
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#include "clang/AST/ExprObjC.h"
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#include "clang/AST/RecursiveASTVisitor.h"
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#include "clang/AST/StmtCXX.h"
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#include "clang/AST/StmtObjC.h"
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#include "clang/AST/TypeLoc.h"
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#include "clang/AST/TypeOrdering.h"
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#include "clang/Basic/TargetInfo.h"
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#include "clang/Lex/Preprocessor.h"
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#include "clang/Sema/Initialization.h"
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#include "clang/Sema/Lookup.h"
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#include "clang/Sema/Scope.h"
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#include "clang/Sema/ScopeInfo.h"
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/SmallVector.h"
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using namespace clang;
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using namespace sema;
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StmtResult Sema::ActOnExprStmt(ExprResult FE) {
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if (FE.isInvalid())
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return StmtError();
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FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(),
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/*DiscardedValue*/ true);
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if (FE.isInvalid())
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return StmtError();
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// C99 6.8.3p2: The expression in an expression statement is evaluated as a
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// void expression for its side effects. Conversion to void allows any
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// operand, even incomplete types.
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// Same thing in for stmt first clause (when expr) and third clause.
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return StmtResult(FE.getAs<Stmt>());
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}
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StmtResult Sema::ActOnExprStmtError() {
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DiscardCleanupsInEvaluationContext();
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return StmtError();
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}
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StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
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bool HasLeadingEmptyMacro) {
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return new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro);
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}
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StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
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SourceLocation EndLoc) {
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DeclGroupRef DG = dg.get();
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// If we have an invalid decl, just return an error.
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if (DG.isNull()) return StmtError();
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return new (Context) DeclStmt(DG, StartLoc, EndLoc);
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}
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void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
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DeclGroupRef DG = dg.get();
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// If we don't have a declaration, or we have an invalid declaration,
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// just return.
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if (DG.isNull() || !DG.isSingleDecl())
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return;
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Decl *decl = DG.getSingleDecl();
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if (!decl || decl->isInvalidDecl())
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return;
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// Only variable declarations are permitted.
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VarDecl *var = dyn_cast<VarDecl>(decl);
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if (!var) {
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Diag(decl->getLocation(), diag::err_non_variable_decl_in_for);
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decl->setInvalidDecl();
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return;
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}
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// foreach variables are never actually initialized in the way that
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// the parser came up with.
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var->setInit(nullptr);
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// In ARC, we don't need to retain the iteration variable of a fast
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// enumeration loop. Rather than actually trying to catch that
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// during declaration processing, we remove the consequences here.
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if (getLangOpts().ObjCAutoRefCount) {
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QualType type = var->getType();
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// Only do this if we inferred the lifetime. Inferred lifetime
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// will show up as a local qualifier because explicit lifetime
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// should have shown up as an AttributedType instead.
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if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) {
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// Add 'const' and mark the variable as pseudo-strong.
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var->setType(type.withConst());
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var->setARCPseudoStrong(true);
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}
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}
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}
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/// \brief Diagnose unused comparisons, both builtin and overloaded operators.
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/// For '==' and '!=', suggest fixits for '=' or '|='.
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///
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/// Adding a cast to void (or other expression wrappers) will prevent the
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/// warning from firing.
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static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) {
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SourceLocation Loc;
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bool IsNotEqual, CanAssign, IsRelational;
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if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
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if (!Op->isComparisonOp())
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return false;
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IsRelational = Op->isRelationalOp();
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Loc = Op->getOperatorLoc();
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IsNotEqual = Op->getOpcode() == BO_NE;
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CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue();
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} else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
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switch (Op->getOperator()) {
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default:
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return false;
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case OO_EqualEqual:
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case OO_ExclaimEqual:
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IsRelational = false;
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break;
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case OO_Less:
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case OO_Greater:
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case OO_GreaterEqual:
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case OO_LessEqual:
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IsRelational = true;
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break;
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}
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Loc = Op->getOperatorLoc();
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IsNotEqual = Op->getOperator() == OO_ExclaimEqual;
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CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue();
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} else {
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// Not a typo-prone comparison.
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return false;
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}
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// Suppress warnings when the operator, suspicious as it may be, comes from
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// a macro expansion.
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if (S.SourceMgr.isMacroBodyExpansion(Loc))
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return false;
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S.Diag(Loc, diag::warn_unused_comparison)
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<< (unsigned)IsRelational << (unsigned)IsNotEqual << E->getSourceRange();
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// If the LHS is a plausible entity to assign to, provide a fixit hint to
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// correct common typos.
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if (!IsRelational && CanAssign) {
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if (IsNotEqual)
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S.Diag(Loc, diag::note_inequality_comparison_to_or_assign)
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<< FixItHint::CreateReplacement(Loc, "|=");
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else
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S.Diag(Loc, diag::note_equality_comparison_to_assign)
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<< FixItHint::CreateReplacement(Loc, "=");
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}
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return true;
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}
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void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
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if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
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return DiagnoseUnusedExprResult(Label->getSubStmt());
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const Expr *E = dyn_cast_or_null<Expr>(S);
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if (!E)
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return;
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// If we are in an unevaluated expression context, then there can be no unused
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// results because the results aren't expected to be used in the first place.
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if (isUnevaluatedContext())
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return;
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SourceLocation ExprLoc = E->IgnoreParenImpCasts()->getExprLoc();
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// In most cases, we don't want to warn if the expression is written in a
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// macro body, or if the macro comes from a system header. If the offending
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// expression is a call to a function with the warn_unused_result attribute,
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// we warn no matter the location. Because of the order in which the various
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// checks need to happen, we factor out the macro-related test here.
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bool ShouldSuppress =
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SourceMgr.isMacroBodyExpansion(ExprLoc) ||
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SourceMgr.isInSystemMacro(ExprLoc);
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const Expr *WarnExpr;
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SourceLocation Loc;
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SourceRange R1, R2;
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if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context))
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return;
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// If this is a GNU statement expression expanded from a macro, it is probably
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// unused because it is a function-like macro that can be used as either an
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// expression or statement. Don't warn, because it is almost certainly a
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// false positive.
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if (isa<StmtExpr>(E) && Loc.isMacroID())
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return;
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// Check if this is the UNREFERENCED_PARAMETER from the Microsoft headers.
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// That macro is frequently used to suppress "unused parameter" warnings,
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// but its implementation makes clang's -Wunused-value fire. Prevent this.
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if (isa<ParenExpr>(E->IgnoreImpCasts()) && Loc.isMacroID()) {
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SourceLocation SpellLoc = Loc;
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if (findMacroSpelling(SpellLoc, "UNREFERENCED_PARAMETER"))
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return;
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}
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// Okay, we have an unused result. Depending on what the base expression is,
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// we might want to make a more specific diagnostic. Check for one of these
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// cases now.
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unsigned DiagID = diag::warn_unused_expr;
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if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E))
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E = Temps->getSubExpr();
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if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
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E = TempExpr->getSubExpr();
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if (DiagnoseUnusedComparison(*this, E))
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return;
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E = WarnExpr;
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if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
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if (E->getType()->isVoidType())
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return;
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// If the callee has attribute pure, const, or warn_unused_result, warn with
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// a more specific message to make it clear what is happening. If the call
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// is written in a macro body, only warn if it has the warn_unused_result
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// attribute.
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if (const Decl *FD = CE->getCalleeDecl()) {
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if (const Attr *A = isa<FunctionDecl>(FD)
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? cast<FunctionDecl>(FD)->getUnusedResultAttr()
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: FD->getAttr<WarnUnusedResultAttr>()) {
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Diag(Loc, diag::warn_unused_result) << A << R1 << R2;
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return;
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}
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if (ShouldSuppress)
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return;
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if (FD->hasAttr<PureAttr>()) {
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Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
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return;
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}
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if (FD->hasAttr<ConstAttr>()) {
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Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
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return;
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}
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}
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} else if (ShouldSuppress)
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return;
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if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
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if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) {
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Diag(Loc, diag::err_arc_unused_init_message) << R1;
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return;
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}
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const ObjCMethodDecl *MD = ME->getMethodDecl();
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if (MD) {
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if (const auto *A = MD->getAttr<WarnUnusedResultAttr>()) {
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Diag(Loc, diag::warn_unused_result) << A << R1 << R2;
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return;
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}
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}
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} else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
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const Expr *Source = POE->getSyntacticForm();
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if (isa<ObjCSubscriptRefExpr>(Source))
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DiagID = diag::warn_unused_container_subscript_expr;
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else
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DiagID = diag::warn_unused_property_expr;
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} else if (const CXXFunctionalCastExpr *FC
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= dyn_cast<CXXFunctionalCastExpr>(E)) {
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const Expr *E = FC->getSubExpr();
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if (const CXXBindTemporaryExpr *TE = dyn_cast<CXXBindTemporaryExpr>(E))
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E = TE->getSubExpr();
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if (isa<CXXTemporaryObjectExpr>(E))
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return;
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if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(E))
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if (const CXXRecordDecl *RD = CE->getType()->getAsCXXRecordDecl())
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if (!RD->getAttr<WarnUnusedAttr>())
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return;
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}
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// Diagnose "(void*) blah" as a typo for "(void) blah".
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else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
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TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
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QualType T = TI->getType();
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// We really do want to use the non-canonical type here.
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if (T == Context.VoidPtrTy) {
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PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>();
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Diag(Loc, diag::warn_unused_voidptr)
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<< FixItHint::CreateRemoval(TL.getStarLoc());
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return;
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}
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}
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if (E->isGLValue() && E->getType().isVolatileQualified()) {
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Diag(Loc, diag::warn_unused_volatile) << R1 << R2;
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return;
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}
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DiagRuntimeBehavior(Loc, nullptr, PDiag(DiagID) << R1 << R2);
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}
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void Sema::ActOnStartOfCompoundStmt() {
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PushCompoundScope();
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}
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void Sema::ActOnFinishOfCompoundStmt() {
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PopCompoundScope();
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}
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sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
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return getCurFunction()->CompoundScopes.back();
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}
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StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
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ArrayRef<Stmt *> Elts, bool isStmtExpr) {
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const unsigned NumElts = Elts.size();
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// If we're in C89 mode, check that we don't have any decls after stmts. If
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// so, emit an extension diagnostic.
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if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) {
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// Note that __extension__ can be around a decl.
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unsigned i = 0;
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// Skip over all declarations.
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for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
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/*empty*/;
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// We found the end of the list or a statement. Scan for another declstmt.
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for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
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/*empty*/;
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if (i != NumElts) {
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Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
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Diag(D->getLocation(), diag::ext_mixed_decls_code);
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}
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}
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// Warn about unused expressions in statements.
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for (unsigned i = 0; i != NumElts; ++i) {
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// Ignore statements that are last in a statement expression.
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if (isStmtExpr && i == NumElts - 1)
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continue;
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DiagnoseUnusedExprResult(Elts[i]);
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}
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// Check for suspicious empty body (null statement) in `for' and `while'
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// statements. Don't do anything for template instantiations, this just adds
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// noise.
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if (NumElts != 0 && !CurrentInstantiationScope &&
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getCurCompoundScope().HasEmptyLoopBodies) {
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for (unsigned i = 0; i != NumElts - 1; ++i)
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DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
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}
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return new (Context) CompoundStmt(Context, Elts, L, R);
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}
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StmtResult
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Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
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SourceLocation DotDotDotLoc, Expr *RHSVal,
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SourceLocation ColonLoc) {
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assert(LHSVal && "missing expression in case statement");
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if (getCurFunction()->SwitchStack.empty()) {
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Diag(CaseLoc, diag::err_case_not_in_switch);
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return StmtError();
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}
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ExprResult LHS =
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CorrectDelayedTyposInExpr(LHSVal, [this](class Expr *E) {
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if (!getLangOpts().CPlusPlus11)
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return VerifyIntegerConstantExpression(E);
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if (Expr *CondExpr =
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getCurFunction()->SwitchStack.back()->getCond()) {
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QualType CondType = CondExpr->getType();
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llvm::APSInt TempVal;
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return CheckConvertedConstantExpression(E, CondType, TempVal,
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CCEK_CaseValue);
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}
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return ExprError();
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});
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if (LHS.isInvalid())
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return StmtError();
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LHSVal = LHS.get();
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if (!getLangOpts().CPlusPlus11) {
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// C99 6.8.4.2p3: The expression shall be an integer constant.
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// However, GCC allows any evaluatable integer expression.
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if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) {
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LHSVal = VerifyIntegerConstantExpression(LHSVal).get();
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if (!LHSVal)
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return StmtError();
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}
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// GCC extension: The expression shall be an integer constant.
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if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) {
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RHSVal = VerifyIntegerConstantExpression(RHSVal).get();
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// Recover from an error by just forgetting about it.
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}
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}
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LHS = ActOnFinishFullExpr(LHSVal, LHSVal->getExprLoc(), false,
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getLangOpts().CPlusPlus11);
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if (LHS.isInvalid())
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return StmtError();
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auto RHS = RHSVal ? ActOnFinishFullExpr(RHSVal, RHSVal->getExprLoc(), false,
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getLangOpts().CPlusPlus11)
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: ExprResult();
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if (RHS.isInvalid())
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return StmtError();
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CaseStmt *CS = new (Context)
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CaseStmt(LHS.get(), RHS.get(), CaseLoc, DotDotDotLoc, ColonLoc);
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getCurFunction()->SwitchStack.back()->addSwitchCase(CS);
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return CS;
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}
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/// ActOnCaseStmtBody - This installs a statement as the body of a case.
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void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) {
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DiagnoseUnusedExprResult(SubStmt);
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CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
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CS->setSubStmt(SubStmt);
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}
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StmtResult
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Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
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Stmt *SubStmt, Scope *CurScope) {
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DiagnoseUnusedExprResult(SubStmt);
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if (getCurFunction()->SwitchStack.empty()) {
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Diag(DefaultLoc, diag::err_default_not_in_switch);
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return SubStmt;
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}
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DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
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getCurFunction()->SwitchStack.back()->addSwitchCase(DS);
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return DS;
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}
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StmtResult
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Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
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SourceLocation ColonLoc, Stmt *SubStmt) {
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// If the label was multiply defined, reject it now.
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if (TheDecl->getStmt()) {
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Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
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Diag(TheDecl->getLocation(), diag::note_previous_definition);
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return SubStmt;
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}
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|
|
// Otherwise, things are good. Fill in the declaration and return it.
|
|
LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt);
|
|
TheDecl->setStmt(LS);
|
|
if (!TheDecl->isGnuLocal()) {
|
|
TheDecl->setLocStart(IdentLoc);
|
|
if (!TheDecl->isMSAsmLabel()) {
|
|
// Don't update the location of MS ASM labels. These will result in
|
|
// a diagnostic, and changing the location here will mess that up.
|
|
TheDecl->setLocation(IdentLoc);
|
|
}
|
|
}
|
|
return LS;
|
|
}
|
|
|
|
StmtResult Sema::ActOnAttributedStmt(SourceLocation AttrLoc,
|
|
ArrayRef<const Attr*> Attrs,
|
|
Stmt *SubStmt) {
|
|
// Fill in the declaration and return it.
|
|
AttributedStmt *LS = AttributedStmt::Create(Context, AttrLoc, Attrs, SubStmt);
|
|
return LS;
|
|
}
|
|
|
|
namespace {
|
|
class CommaVisitor : public EvaluatedExprVisitor<CommaVisitor> {
|
|
typedef EvaluatedExprVisitor<CommaVisitor> Inherited;
|
|
Sema &SemaRef;
|
|
public:
|
|
CommaVisitor(Sema &SemaRef) : Inherited(SemaRef.Context), SemaRef(SemaRef) {}
|
|
void VisitBinaryOperator(BinaryOperator *E) {
|
|
if (E->getOpcode() == BO_Comma)
|
|
SemaRef.DiagnoseCommaOperator(E->getLHS(), E->getExprLoc());
|
|
EvaluatedExprVisitor<CommaVisitor>::VisitBinaryOperator(E);
|
|
}
|
|
};
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnIfStmt(SourceLocation IfLoc, bool IsConstexpr, Stmt *InitStmt,
|
|
ConditionResult Cond,
|
|
Stmt *thenStmt, SourceLocation ElseLoc,
|
|
Stmt *elseStmt) {
|
|
if (Cond.isInvalid())
|
|
Cond = ConditionResult(
|
|
*this, nullptr,
|
|
MakeFullExpr(new (Context) OpaqueValueExpr(SourceLocation(),
|
|
Context.BoolTy, VK_RValue),
|
|
IfLoc),
|
|
false);
|
|
|
|
Expr *CondExpr = Cond.get().second;
|
|
if (!Diags.isIgnored(diag::warn_comma_operator,
|
|
CondExpr->getExprLoc()))
|
|
CommaVisitor(*this).Visit(CondExpr);
|
|
|
|
if (!elseStmt)
|
|
DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), thenStmt,
|
|
diag::warn_empty_if_body);
|
|
|
|
return BuildIfStmt(IfLoc, IsConstexpr, InitStmt, Cond, thenStmt, ElseLoc,
|
|
elseStmt);
|
|
}
|
|
|
|
StmtResult Sema::BuildIfStmt(SourceLocation IfLoc, bool IsConstexpr,
|
|
Stmt *InitStmt, ConditionResult Cond,
|
|
Stmt *thenStmt, SourceLocation ElseLoc,
|
|
Stmt *elseStmt) {
|
|
if (Cond.isInvalid())
|
|
return StmtError();
|
|
|
|
if (IsConstexpr || isa<ObjCAvailabilityCheckExpr>(Cond.get().second))
|
|
getCurFunction()->setHasBranchProtectedScope();
|
|
|
|
DiagnoseUnusedExprResult(thenStmt);
|
|
DiagnoseUnusedExprResult(elseStmt);
|
|
|
|
return new (Context)
|
|
IfStmt(Context, IfLoc, IsConstexpr, InitStmt, Cond.get().first,
|
|
Cond.get().second, thenStmt, ElseLoc, elseStmt);
|
|
}
|
|
|
|
namespace {
|
|
struct CaseCompareFunctor {
|
|
bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
|
|
const llvm::APSInt &RHS) {
|
|
return LHS.first < RHS;
|
|
}
|
|
bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
|
|
const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
|
|
return LHS.first < RHS.first;
|
|
}
|
|
bool operator()(const llvm::APSInt &LHS,
|
|
const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
|
|
return LHS < RHS.first;
|
|
}
|
|
};
|
|
}
|
|
|
|
/// CmpCaseVals - Comparison predicate for sorting case values.
|
|
///
|
|
static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
|
|
const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
|
|
if (lhs.first < rhs.first)
|
|
return true;
|
|
|
|
if (lhs.first == rhs.first &&
|
|
lhs.second->getCaseLoc().getRawEncoding()
|
|
< rhs.second->getCaseLoc().getRawEncoding())
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/// CmpEnumVals - Comparison predicate for sorting enumeration values.
|
|
///
|
|
static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
|
|
const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
|
|
{
|
|
return lhs.first < rhs.first;
|
|
}
|
|
|
|
/// EqEnumVals - Comparison preficate for uniqing enumeration values.
|
|
///
|
|
static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
|
|
const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
|
|
{
|
|
return lhs.first == rhs.first;
|
|
}
|
|
|
|
/// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of
|
|
/// potentially integral-promoted expression @p expr.
|
|
static QualType GetTypeBeforeIntegralPromotion(Expr *&expr) {
|
|
if (ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(expr))
|
|
expr = cleanups->getSubExpr();
|
|
while (ImplicitCastExpr *impcast = dyn_cast<ImplicitCastExpr>(expr)) {
|
|
if (impcast->getCastKind() != CK_IntegralCast) break;
|
|
expr = impcast->getSubExpr();
|
|
}
|
|
return expr->getType();
|
|
}
|
|
|
|
ExprResult Sema::CheckSwitchCondition(SourceLocation SwitchLoc, Expr *Cond) {
|
|
class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
|
|
Expr *Cond;
|
|
|
|
public:
|
|
SwitchConvertDiagnoser(Expr *Cond)
|
|
: ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true),
|
|
Cond(Cond) {}
|
|
|
|
SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
|
|
QualType T) override {
|
|
return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
|
|
}
|
|
|
|
SemaDiagnosticBuilder diagnoseIncomplete(
|
|
Sema &S, SourceLocation Loc, QualType T) override {
|
|
return S.Diag(Loc, diag::err_switch_incomplete_class_type)
|
|
<< T << Cond->getSourceRange();
|
|
}
|
|
|
|
SemaDiagnosticBuilder diagnoseExplicitConv(
|
|
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
|
|
return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
|
|
}
|
|
|
|
SemaDiagnosticBuilder noteExplicitConv(
|
|
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
|
|
return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
|
|
<< ConvTy->isEnumeralType() << ConvTy;
|
|
}
|
|
|
|
SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
|
|
QualType T) override {
|
|
return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
|
|
}
|
|
|
|
SemaDiagnosticBuilder noteAmbiguous(
|
|
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
|
|
return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
|
|
<< ConvTy->isEnumeralType() << ConvTy;
|
|
}
|
|
|
|
SemaDiagnosticBuilder diagnoseConversion(
|
|
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
|
|
llvm_unreachable("conversion functions are permitted");
|
|
}
|
|
} SwitchDiagnoser(Cond);
|
|
|
|
ExprResult CondResult =
|
|
PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser);
|
|
if (CondResult.isInvalid())
|
|
return ExprError();
|
|
|
|
// C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
|
|
return UsualUnaryConversions(CondResult.get());
|
|
}
|
|
|
|
StmtResult Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc,
|
|
Stmt *InitStmt, ConditionResult Cond) {
|
|
if (Cond.isInvalid())
|
|
return StmtError();
|
|
|
|
getCurFunction()->setHasBranchIntoScope();
|
|
|
|
SwitchStmt *SS = new (Context)
|
|
SwitchStmt(Context, InitStmt, Cond.get().first, Cond.get().second);
|
|
getCurFunction()->SwitchStack.push_back(SS);
|
|
return SS;
|
|
}
|
|
|
|
static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
|
|
Val = Val.extOrTrunc(BitWidth);
|
|
Val.setIsSigned(IsSigned);
|
|
}
|
|
|
|
/// Check the specified case value is in range for the given unpromoted switch
|
|
/// type.
|
|
static void checkCaseValue(Sema &S, SourceLocation Loc, const llvm::APSInt &Val,
|
|
unsigned UnpromotedWidth, bool UnpromotedSign) {
|
|
// If the case value was signed and negative and the switch expression is
|
|
// unsigned, don't bother to warn: this is implementation-defined behavior.
|
|
// FIXME: Introduce a second, default-ignored warning for this case?
|
|
if (UnpromotedWidth < Val.getBitWidth()) {
|
|
llvm::APSInt ConvVal(Val);
|
|
AdjustAPSInt(ConvVal, UnpromotedWidth, UnpromotedSign);
|
|
AdjustAPSInt(ConvVal, Val.getBitWidth(), Val.isSigned());
|
|
// FIXME: Use different diagnostics for overflow in conversion to promoted
|
|
// type versus "switch expression cannot have this value". Use proper
|
|
// IntRange checking rather than just looking at the unpromoted type here.
|
|
if (ConvVal != Val)
|
|
S.Diag(Loc, diag::warn_case_value_overflow) << Val.toString(10)
|
|
<< ConvVal.toString(10);
|
|
}
|
|
}
|
|
|
|
typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> EnumValsTy;
|
|
|
|
/// Returns true if we should emit a diagnostic about this case expression not
|
|
/// being a part of the enum used in the switch controlling expression.
|
|
static bool ShouldDiagnoseSwitchCaseNotInEnum(const Sema &S,
|
|
const EnumDecl *ED,
|
|
const Expr *CaseExpr,
|
|
EnumValsTy::iterator &EI,
|
|
EnumValsTy::iterator &EIEnd,
|
|
const llvm::APSInt &Val) {
|
|
if (!ED->isClosed())
|
|
return false;
|
|
|
|
if (const DeclRefExpr *DRE =
|
|
dyn_cast<DeclRefExpr>(CaseExpr->IgnoreParenImpCasts())) {
|
|
if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
|
|
QualType VarType = VD->getType();
|
|
QualType EnumType = S.Context.getTypeDeclType(ED);
|
|
if (VD->hasGlobalStorage() && VarType.isConstQualified() &&
|
|
S.Context.hasSameUnqualifiedType(EnumType, VarType))
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (ED->hasAttr<FlagEnumAttr>())
|
|
return !S.IsValueInFlagEnum(ED, Val, false);
|
|
|
|
while (EI != EIEnd && EI->first < Val)
|
|
EI++;
|
|
|
|
if (EI != EIEnd && EI->first == Val)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
|
|
Stmt *BodyStmt) {
|
|
SwitchStmt *SS = cast<SwitchStmt>(Switch);
|
|
assert(SS == getCurFunction()->SwitchStack.back() &&
|
|
"switch stack missing push/pop!");
|
|
|
|
getCurFunction()->SwitchStack.pop_back();
|
|
|
|
if (!BodyStmt) return StmtError();
|
|
SS->setBody(BodyStmt, SwitchLoc);
|
|
|
|
Expr *CondExpr = SS->getCond();
|
|
if (!CondExpr) return StmtError();
|
|
|
|
QualType CondType = CondExpr->getType();
|
|
|
|
Expr *CondExprBeforePromotion = CondExpr;
|
|
QualType CondTypeBeforePromotion =
|
|
GetTypeBeforeIntegralPromotion(CondExprBeforePromotion);
|
|
|
|
// C++ 6.4.2.p2:
|
|
// Integral promotions are performed (on the switch condition).
|
|
//
|
|
// A case value unrepresentable by the original switch condition
|
|
// type (before the promotion) doesn't make sense, even when it can
|
|
// be represented by the promoted type. Therefore we need to find
|
|
// the pre-promotion type of the switch condition.
|
|
if (!CondExpr->isTypeDependent()) {
|
|
// We have already converted the expression to an integral or enumeration
|
|
// type, when we started the switch statement. If we don't have an
|
|
// appropriate type now, just return an error.
|
|
if (!CondType->isIntegralOrEnumerationType())
|
|
return StmtError();
|
|
|
|
if (CondExpr->isKnownToHaveBooleanValue()) {
|
|
// switch(bool_expr) {...} is often a programmer error, e.g.
|
|
// switch(n && mask) { ... } // Doh - should be "n & mask".
|
|
// One can always use an if statement instead of switch(bool_expr).
|
|
Diag(SwitchLoc, diag::warn_bool_switch_condition)
|
|
<< CondExpr->getSourceRange();
|
|
}
|
|
}
|
|
|
|
// Get the bitwidth of the switched-on value after promotions. We must
|
|
// convert the integer case values to this width before comparison.
|
|
bool HasDependentValue
|
|
= CondExpr->isTypeDependent() || CondExpr->isValueDependent();
|
|
unsigned CondWidth = HasDependentValue ? 0 : Context.getIntWidth(CondType);
|
|
bool CondIsSigned = CondType->isSignedIntegerOrEnumerationType();
|
|
|
|
// Get the width and signedness that the condition might actually have, for
|
|
// warning purposes.
|
|
// FIXME: Grab an IntRange for the condition rather than using the unpromoted
|
|
// type.
|
|
unsigned CondWidthBeforePromotion
|
|
= HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion);
|
|
bool CondIsSignedBeforePromotion
|
|
= CondTypeBeforePromotion->isSignedIntegerOrEnumerationType();
|
|
|
|
// Accumulate all of the case values in a vector so that we can sort them
|
|
// and detect duplicates. This vector contains the APInt for the case after
|
|
// it has been converted to the condition type.
|
|
typedef SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
|
|
CaseValsTy CaseVals;
|
|
|
|
// Keep track of any GNU case ranges we see. The APSInt is the low value.
|
|
typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy;
|
|
CaseRangesTy CaseRanges;
|
|
|
|
DefaultStmt *TheDefaultStmt = nullptr;
|
|
|
|
bool CaseListIsErroneous = false;
|
|
|
|
for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue;
|
|
SC = SC->getNextSwitchCase()) {
|
|
|
|
if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) {
|
|
if (TheDefaultStmt) {
|
|
Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined);
|
|
Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev);
|
|
|
|
// FIXME: Remove the default statement from the switch block so that
|
|
// we'll return a valid AST. This requires recursing down the AST and
|
|
// finding it, not something we are set up to do right now. For now,
|
|
// just lop the entire switch stmt out of the AST.
|
|
CaseListIsErroneous = true;
|
|
}
|
|
TheDefaultStmt = DS;
|
|
|
|
} else {
|
|
CaseStmt *CS = cast<CaseStmt>(SC);
|
|
|
|
Expr *Lo = CS->getLHS();
|
|
|
|
if (Lo->isTypeDependent() || Lo->isValueDependent()) {
|
|
HasDependentValue = true;
|
|
break;
|
|
}
|
|
|
|
llvm::APSInt LoVal;
|
|
|
|
if (getLangOpts().CPlusPlus11) {
|
|
// C++11 [stmt.switch]p2: the constant-expression shall be a converted
|
|
// constant expression of the promoted type of the switch condition.
|
|
ExprResult ConvLo =
|
|
CheckConvertedConstantExpression(Lo, CondType, LoVal, CCEK_CaseValue);
|
|
if (ConvLo.isInvalid()) {
|
|
CaseListIsErroneous = true;
|
|
continue;
|
|
}
|
|
Lo = ConvLo.get();
|
|
} else {
|
|
// We already verified that the expression has a i-c-e value (C99
|
|
// 6.8.4.2p3) - get that value now.
|
|
LoVal = Lo->EvaluateKnownConstInt(Context);
|
|
|
|
// If the LHS is not the same type as the condition, insert an implicit
|
|
// cast.
|
|
Lo = DefaultLvalueConversion(Lo).get();
|
|
Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).get();
|
|
}
|
|
|
|
// Check the unconverted value is within the range of possible values of
|
|
// the switch expression.
|
|
checkCaseValue(*this, Lo->getLocStart(), LoVal,
|
|
CondWidthBeforePromotion, CondIsSignedBeforePromotion);
|
|
|
|
// Convert the value to the same width/sign as the condition.
|
|
AdjustAPSInt(LoVal, CondWidth, CondIsSigned);
|
|
|
|
CS->setLHS(Lo);
|
|
|
|
// If this is a case range, remember it in CaseRanges, otherwise CaseVals.
|
|
if (CS->getRHS()) {
|
|
if (CS->getRHS()->isTypeDependent() ||
|
|
CS->getRHS()->isValueDependent()) {
|
|
HasDependentValue = true;
|
|
break;
|
|
}
|
|
CaseRanges.push_back(std::make_pair(LoVal, CS));
|
|
} else
|
|
CaseVals.push_back(std::make_pair(LoVal, CS));
|
|
}
|
|
}
|
|
|
|
if (!HasDependentValue) {
|
|
// If we don't have a default statement, check whether the
|
|
// condition is constant.
|
|
llvm::APSInt ConstantCondValue;
|
|
bool HasConstantCond = false;
|
|
if (!HasDependentValue && !TheDefaultStmt) {
|
|
HasConstantCond = CondExpr->EvaluateAsInt(ConstantCondValue, Context,
|
|
Expr::SE_AllowSideEffects);
|
|
assert(!HasConstantCond ||
|
|
(ConstantCondValue.getBitWidth() == CondWidth &&
|
|
ConstantCondValue.isSigned() == CondIsSigned));
|
|
}
|
|
bool ShouldCheckConstantCond = HasConstantCond;
|
|
|
|
// Sort all the scalar case values so we can easily detect duplicates.
|
|
std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals);
|
|
|
|
if (!CaseVals.empty()) {
|
|
for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) {
|
|
if (ShouldCheckConstantCond &&
|
|
CaseVals[i].first == ConstantCondValue)
|
|
ShouldCheckConstantCond = false;
|
|
|
|
if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) {
|
|
// If we have a duplicate, report it.
|
|
// First, determine if either case value has a name
|
|
StringRef PrevString, CurrString;
|
|
Expr *PrevCase = CaseVals[i-1].second->getLHS()->IgnoreParenCasts();
|
|
Expr *CurrCase = CaseVals[i].second->getLHS()->IgnoreParenCasts();
|
|
if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(PrevCase)) {
|
|
PrevString = DeclRef->getDecl()->getName();
|
|
}
|
|
if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(CurrCase)) {
|
|
CurrString = DeclRef->getDecl()->getName();
|
|
}
|
|
SmallString<16> CaseValStr;
|
|
CaseVals[i-1].first.toString(CaseValStr);
|
|
|
|
if (PrevString == CurrString)
|
|
Diag(CaseVals[i].second->getLHS()->getLocStart(),
|
|
diag::err_duplicate_case) <<
|
|
(PrevString.empty() ? StringRef(CaseValStr) : PrevString);
|
|
else
|
|
Diag(CaseVals[i].second->getLHS()->getLocStart(),
|
|
diag::err_duplicate_case_differing_expr) <<
|
|
(PrevString.empty() ? StringRef(CaseValStr) : PrevString) <<
|
|
(CurrString.empty() ? StringRef(CaseValStr) : CurrString) <<
|
|
CaseValStr;
|
|
|
|
Diag(CaseVals[i-1].second->getLHS()->getLocStart(),
|
|
diag::note_duplicate_case_prev);
|
|
// FIXME: We really want to remove the bogus case stmt from the
|
|
// substmt, but we have no way to do this right now.
|
|
CaseListIsErroneous = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Detect duplicate case ranges, which usually don't exist at all in
|
|
// the first place.
|
|
if (!CaseRanges.empty()) {
|
|
// Sort all the case ranges by their low value so we can easily detect
|
|
// overlaps between ranges.
|
|
std::stable_sort(CaseRanges.begin(), CaseRanges.end());
|
|
|
|
// Scan the ranges, computing the high values and removing empty ranges.
|
|
std::vector<llvm::APSInt> HiVals;
|
|
for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
|
|
llvm::APSInt &LoVal = CaseRanges[i].first;
|
|
CaseStmt *CR = CaseRanges[i].second;
|
|
Expr *Hi = CR->getRHS();
|
|
llvm::APSInt HiVal;
|
|
|
|
if (getLangOpts().CPlusPlus11) {
|
|
// C++11 [stmt.switch]p2: the constant-expression shall be a converted
|
|
// constant expression of the promoted type of the switch condition.
|
|
ExprResult ConvHi =
|
|
CheckConvertedConstantExpression(Hi, CondType, HiVal,
|
|
CCEK_CaseValue);
|
|
if (ConvHi.isInvalid()) {
|
|
CaseListIsErroneous = true;
|
|
continue;
|
|
}
|
|
Hi = ConvHi.get();
|
|
} else {
|
|
HiVal = Hi->EvaluateKnownConstInt(Context);
|
|
|
|
// If the RHS is not the same type as the condition, insert an
|
|
// implicit cast.
|
|
Hi = DefaultLvalueConversion(Hi).get();
|
|
Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).get();
|
|
}
|
|
|
|
// Check the unconverted value is within the range of possible values of
|
|
// the switch expression.
|
|
checkCaseValue(*this, Hi->getLocStart(), HiVal,
|
|
CondWidthBeforePromotion, CondIsSignedBeforePromotion);
|
|
|
|
// Convert the value to the same width/sign as the condition.
|
|
AdjustAPSInt(HiVal, CondWidth, CondIsSigned);
|
|
|
|
CR->setRHS(Hi);
|
|
|
|
// If the low value is bigger than the high value, the case is empty.
|
|
if (LoVal > HiVal) {
|
|
Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range)
|
|
<< SourceRange(CR->getLHS()->getLocStart(),
|
|
Hi->getLocEnd());
|
|
CaseRanges.erase(CaseRanges.begin()+i);
|
|
--i;
|
|
--e;
|
|
continue;
|
|
}
|
|
|
|
if (ShouldCheckConstantCond &&
|
|
LoVal <= ConstantCondValue &&
|
|
ConstantCondValue <= HiVal)
|
|
ShouldCheckConstantCond = false;
|
|
|
|
HiVals.push_back(HiVal);
|
|
}
|
|
|
|
// Rescan the ranges, looking for overlap with singleton values and other
|
|
// ranges. Since the range list is sorted, we only need to compare case
|
|
// ranges with their neighbors.
|
|
for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
|
|
llvm::APSInt &CRLo = CaseRanges[i].first;
|
|
llvm::APSInt &CRHi = HiVals[i];
|
|
CaseStmt *CR = CaseRanges[i].second;
|
|
|
|
// Check to see whether the case range overlaps with any
|
|
// singleton cases.
|
|
CaseStmt *OverlapStmt = nullptr;
|
|
llvm::APSInt OverlapVal(32);
|
|
|
|
// Find the smallest value >= the lower bound. If I is in the
|
|
// case range, then we have overlap.
|
|
CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(),
|
|
CaseVals.end(), CRLo,
|
|
CaseCompareFunctor());
|
|
if (I != CaseVals.end() && I->first < CRHi) {
|
|
OverlapVal = I->first; // Found overlap with scalar.
|
|
OverlapStmt = I->second;
|
|
}
|
|
|
|
// Find the smallest value bigger than the upper bound.
|
|
I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
|
|
if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
|
|
OverlapVal = (I-1)->first; // Found overlap with scalar.
|
|
OverlapStmt = (I-1)->second;
|
|
}
|
|
|
|
// Check to see if this case stmt overlaps with the subsequent
|
|
// case range.
|
|
if (i && CRLo <= HiVals[i-1]) {
|
|
OverlapVal = HiVals[i-1]; // Found overlap with range.
|
|
OverlapStmt = CaseRanges[i-1].second;
|
|
}
|
|
|
|
if (OverlapStmt) {
|
|
// If we have a duplicate, report it.
|
|
Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case)
|
|
<< OverlapVal.toString(10);
|
|
Diag(OverlapStmt->getLHS()->getLocStart(),
|
|
diag::note_duplicate_case_prev);
|
|
// FIXME: We really want to remove the bogus case stmt from the
|
|
// substmt, but we have no way to do this right now.
|
|
CaseListIsErroneous = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Complain if we have a constant condition and we didn't find a match.
|
|
if (!CaseListIsErroneous && ShouldCheckConstantCond) {
|
|
// TODO: it would be nice if we printed enums as enums, chars as
|
|
// chars, etc.
|
|
Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition)
|
|
<< ConstantCondValue.toString(10)
|
|
<< CondExpr->getSourceRange();
|
|
}
|
|
|
|
// Check to see if switch is over an Enum and handles all of its
|
|
// values. We only issue a warning if there is not 'default:', but
|
|
// we still do the analysis to preserve this information in the AST
|
|
// (which can be used by flow-based analyes).
|
|
//
|
|
const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>();
|
|
|
|
// If switch has default case, then ignore it.
|
|
if (!CaseListIsErroneous && !HasConstantCond && ET &&
|
|
ET->getDecl()->isCompleteDefinition()) {
|
|
const EnumDecl *ED = ET->getDecl();
|
|
EnumValsTy EnumVals;
|
|
|
|
// Gather all enum values, set their type and sort them,
|
|
// allowing easier comparison with CaseVals.
|
|
for (auto *EDI : ED->enumerators()) {
|
|
llvm::APSInt Val = EDI->getInitVal();
|
|
AdjustAPSInt(Val, CondWidth, CondIsSigned);
|
|
EnumVals.push_back(std::make_pair(Val, EDI));
|
|
}
|
|
std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
|
|
auto EI = EnumVals.begin(), EIEnd =
|
|
std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
|
|
|
|
// See which case values aren't in enum.
|
|
for (CaseValsTy::const_iterator CI = CaseVals.begin();
|
|
CI != CaseVals.end(); CI++) {
|
|
Expr *CaseExpr = CI->second->getLHS();
|
|
if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
|
|
CI->first))
|
|
Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
|
|
<< CondTypeBeforePromotion;
|
|
}
|
|
|
|
// See which of case ranges aren't in enum
|
|
EI = EnumVals.begin();
|
|
for (CaseRangesTy::const_iterator RI = CaseRanges.begin();
|
|
RI != CaseRanges.end(); RI++) {
|
|
Expr *CaseExpr = RI->second->getLHS();
|
|
if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
|
|
RI->first))
|
|
Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
|
|
<< CondTypeBeforePromotion;
|
|
|
|
llvm::APSInt Hi =
|
|
RI->second->getRHS()->EvaluateKnownConstInt(Context);
|
|
AdjustAPSInt(Hi, CondWidth, CondIsSigned);
|
|
|
|
CaseExpr = RI->second->getRHS();
|
|
if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
|
|
Hi))
|
|
Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
|
|
<< CondTypeBeforePromotion;
|
|
}
|
|
|
|
// Check which enum vals aren't in switch
|
|
auto CI = CaseVals.begin();
|
|
auto RI = CaseRanges.begin();
|
|
bool hasCasesNotInSwitch = false;
|
|
|
|
SmallVector<DeclarationName,8> UnhandledNames;
|
|
|
|
for (EI = EnumVals.begin(); EI != EIEnd; EI++){
|
|
// Drop unneeded case values
|
|
while (CI != CaseVals.end() && CI->first < EI->first)
|
|
CI++;
|
|
|
|
if (CI != CaseVals.end() && CI->first == EI->first)
|
|
continue;
|
|
|
|
// Drop unneeded case ranges
|
|
for (; RI != CaseRanges.end(); RI++) {
|
|
llvm::APSInt Hi =
|
|
RI->second->getRHS()->EvaluateKnownConstInt(Context);
|
|
AdjustAPSInt(Hi, CondWidth, CondIsSigned);
|
|
if (EI->first <= Hi)
|
|
break;
|
|
}
|
|
|
|
if (RI == CaseRanges.end() || EI->first < RI->first) {
|
|
hasCasesNotInSwitch = true;
|
|
UnhandledNames.push_back(EI->second->getDeclName());
|
|
}
|
|
}
|
|
|
|
if (TheDefaultStmt && UnhandledNames.empty() && ED->isClosedNonFlag())
|
|
Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
|
|
|
|
// Produce a nice diagnostic if multiple values aren't handled.
|
|
if (!UnhandledNames.empty()) {
|
|
DiagnosticBuilder DB = Diag(CondExpr->getExprLoc(),
|
|
TheDefaultStmt ? diag::warn_def_missing_case
|
|
: diag::warn_missing_case)
|
|
<< (int)UnhandledNames.size();
|
|
|
|
for (size_t I = 0, E = std::min(UnhandledNames.size(), (size_t)3);
|
|
I != E; ++I)
|
|
DB << UnhandledNames[I];
|
|
}
|
|
|
|
if (!hasCasesNotInSwitch)
|
|
SS->setAllEnumCasesCovered();
|
|
}
|
|
}
|
|
|
|
if (BodyStmt)
|
|
DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), BodyStmt,
|
|
diag::warn_empty_switch_body);
|
|
|
|
// FIXME: If the case list was broken is some way, we don't have a good system
|
|
// to patch it up. Instead, just return the whole substmt as broken.
|
|
if (CaseListIsErroneous)
|
|
return StmtError();
|
|
|
|
return SS;
|
|
}
|
|
|
|
void
|
|
Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
|
|
Expr *SrcExpr) {
|
|
if (Diags.isIgnored(diag::warn_not_in_enum_assignment, SrcExpr->getExprLoc()))
|
|
return;
|
|
|
|
if (const EnumType *ET = DstType->getAs<EnumType>())
|
|
if (!Context.hasSameUnqualifiedType(SrcType, DstType) &&
|
|
SrcType->isIntegerType()) {
|
|
if (!SrcExpr->isTypeDependent() && !SrcExpr->isValueDependent() &&
|
|
SrcExpr->isIntegerConstantExpr(Context)) {
|
|
// Get the bitwidth of the enum value before promotions.
|
|
unsigned DstWidth = Context.getIntWidth(DstType);
|
|
bool DstIsSigned = DstType->isSignedIntegerOrEnumerationType();
|
|
|
|
llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context);
|
|
AdjustAPSInt(RhsVal, DstWidth, DstIsSigned);
|
|
const EnumDecl *ED = ET->getDecl();
|
|
|
|
if (!ED->isClosed())
|
|
return;
|
|
|
|
if (ED->hasAttr<FlagEnumAttr>()) {
|
|
if (!IsValueInFlagEnum(ED, RhsVal, true))
|
|
Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
|
|
<< DstType.getUnqualifiedType();
|
|
} else {
|
|
typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64>
|
|
EnumValsTy;
|
|
EnumValsTy EnumVals;
|
|
|
|
// Gather all enum values, set their type and sort them,
|
|
// allowing easier comparison with rhs constant.
|
|
for (auto *EDI : ED->enumerators()) {
|
|
llvm::APSInt Val = EDI->getInitVal();
|
|
AdjustAPSInt(Val, DstWidth, DstIsSigned);
|
|
EnumVals.push_back(std::make_pair(Val, EDI));
|
|
}
|
|
if (EnumVals.empty())
|
|
return;
|
|
std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
|
|
EnumValsTy::iterator EIend =
|
|
std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
|
|
|
|
// See which values aren't in the enum.
|
|
EnumValsTy::const_iterator EI = EnumVals.begin();
|
|
while (EI != EIend && EI->first < RhsVal)
|
|
EI++;
|
|
if (EI == EIend || EI->first != RhsVal) {
|
|
Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
|
|
<< DstType.getUnqualifiedType();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
StmtResult Sema::ActOnWhileStmt(SourceLocation WhileLoc, ConditionResult Cond,
|
|
Stmt *Body) {
|
|
if (Cond.isInvalid())
|
|
return StmtError();
|
|
|
|
auto CondVal = Cond.get();
|
|
CheckBreakContinueBinding(CondVal.second);
|
|
|
|
if (CondVal.second &&
|
|
!Diags.isIgnored(diag::warn_comma_operator, CondVal.second->getExprLoc()))
|
|
CommaVisitor(*this).Visit(CondVal.second);
|
|
|
|
DiagnoseUnusedExprResult(Body);
|
|
|
|
if (isa<NullStmt>(Body))
|
|
getCurCompoundScope().setHasEmptyLoopBodies();
|
|
|
|
return new (Context)
|
|
WhileStmt(Context, CondVal.first, CondVal.second, Body, WhileLoc);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
|
|
SourceLocation WhileLoc, SourceLocation CondLParen,
|
|
Expr *Cond, SourceLocation CondRParen) {
|
|
assert(Cond && "ActOnDoStmt(): missing expression");
|
|
|
|
CheckBreakContinueBinding(Cond);
|
|
ExprResult CondResult = CheckBooleanCondition(DoLoc, Cond);
|
|
if (CondResult.isInvalid())
|
|
return StmtError();
|
|
Cond = CondResult.get();
|
|
|
|
CondResult = ActOnFinishFullExpr(Cond, DoLoc);
|
|
if (CondResult.isInvalid())
|
|
return StmtError();
|
|
Cond = CondResult.get();
|
|
|
|
DiagnoseUnusedExprResult(Body);
|
|
|
|
return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);
|
|
}
|
|
|
|
namespace {
|
|
// This visitor will traverse a conditional statement and store all
|
|
// the evaluated decls into a vector. Simple is set to true if none
|
|
// of the excluded constructs are used.
|
|
class DeclExtractor : public EvaluatedExprVisitor<DeclExtractor> {
|
|
llvm::SmallPtrSetImpl<VarDecl*> &Decls;
|
|
SmallVectorImpl<SourceRange> &Ranges;
|
|
bool Simple;
|
|
public:
|
|
typedef EvaluatedExprVisitor<DeclExtractor> Inherited;
|
|
|
|
DeclExtractor(Sema &S, llvm::SmallPtrSetImpl<VarDecl*> &Decls,
|
|
SmallVectorImpl<SourceRange> &Ranges) :
|
|
Inherited(S.Context),
|
|
Decls(Decls),
|
|
Ranges(Ranges),
|
|
Simple(true) {}
|
|
|
|
bool isSimple() { return Simple; }
|
|
|
|
// Replaces the method in EvaluatedExprVisitor.
|
|
void VisitMemberExpr(MemberExpr* E) {
|
|
Simple = false;
|
|
}
|
|
|
|
// Any Stmt not whitelisted will cause the condition to be marked complex.
|
|
void VisitStmt(Stmt *S) {
|
|
Simple = false;
|
|
}
|
|
|
|
void VisitBinaryOperator(BinaryOperator *E) {
|
|
Visit(E->getLHS());
|
|
Visit(E->getRHS());
|
|
}
|
|
|
|
void VisitCastExpr(CastExpr *E) {
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void VisitUnaryOperator(UnaryOperator *E) {
|
|
// Skip checking conditionals with derefernces.
|
|
if (E->getOpcode() == UO_Deref)
|
|
Simple = false;
|
|
else
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void VisitConditionalOperator(ConditionalOperator *E) {
|
|
Visit(E->getCond());
|
|
Visit(E->getTrueExpr());
|
|
Visit(E->getFalseExpr());
|
|
}
|
|
|
|
void VisitParenExpr(ParenExpr *E) {
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
|
|
Visit(E->getOpaqueValue()->getSourceExpr());
|
|
Visit(E->getFalseExpr());
|
|
}
|
|
|
|
void VisitIntegerLiteral(IntegerLiteral *E) { }
|
|
void VisitFloatingLiteral(FloatingLiteral *E) { }
|
|
void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) { }
|
|
void VisitCharacterLiteral(CharacterLiteral *E) { }
|
|
void VisitGNUNullExpr(GNUNullExpr *E) { }
|
|
void VisitImaginaryLiteral(ImaginaryLiteral *E) { }
|
|
|
|
void VisitDeclRefExpr(DeclRefExpr *E) {
|
|
VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
|
|
if (!VD) return;
|
|
|
|
Ranges.push_back(E->getSourceRange());
|
|
|
|
Decls.insert(VD);
|
|
}
|
|
|
|
}; // end class DeclExtractor
|
|
|
|
// DeclMatcher checks to see if the decls are used in a non-evaluated
|
|
// context.
|
|
class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> {
|
|
llvm::SmallPtrSetImpl<VarDecl*> &Decls;
|
|
bool FoundDecl;
|
|
|
|
public:
|
|
typedef EvaluatedExprVisitor<DeclMatcher> Inherited;
|
|
|
|
DeclMatcher(Sema &S, llvm::SmallPtrSetImpl<VarDecl*> &Decls,
|
|
Stmt *Statement) :
|
|
Inherited(S.Context), Decls(Decls), FoundDecl(false) {
|
|
if (!Statement) return;
|
|
|
|
Visit(Statement);
|
|
}
|
|
|
|
void VisitReturnStmt(ReturnStmt *S) {
|
|
FoundDecl = true;
|
|
}
|
|
|
|
void VisitBreakStmt(BreakStmt *S) {
|
|
FoundDecl = true;
|
|
}
|
|
|
|
void VisitGotoStmt(GotoStmt *S) {
|
|
FoundDecl = true;
|
|
}
|
|
|
|
void VisitCastExpr(CastExpr *E) {
|
|
if (E->getCastKind() == CK_LValueToRValue)
|
|
CheckLValueToRValueCast(E->getSubExpr());
|
|
else
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void CheckLValueToRValueCast(Expr *E) {
|
|
E = E->IgnoreParenImpCasts();
|
|
|
|
if (isa<DeclRefExpr>(E)) {
|
|
return;
|
|
}
|
|
|
|
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
|
|
Visit(CO->getCond());
|
|
CheckLValueToRValueCast(CO->getTrueExpr());
|
|
CheckLValueToRValueCast(CO->getFalseExpr());
|
|
return;
|
|
}
|
|
|
|
if (BinaryConditionalOperator *BCO =
|
|
dyn_cast<BinaryConditionalOperator>(E)) {
|
|
CheckLValueToRValueCast(BCO->getOpaqueValue()->getSourceExpr());
|
|
CheckLValueToRValueCast(BCO->getFalseExpr());
|
|
return;
|
|
}
|
|
|
|
Visit(E);
|
|
}
|
|
|
|
void VisitDeclRefExpr(DeclRefExpr *E) {
|
|
if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
|
|
if (Decls.count(VD))
|
|
FoundDecl = true;
|
|
}
|
|
|
|
void VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
|
|
// Only need to visit the semantics for POE.
|
|
// SyntaticForm doesn't really use the Decal.
|
|
for (auto *S : POE->semantics()) {
|
|
if (auto *OVE = dyn_cast<OpaqueValueExpr>(S))
|
|
// Look past the OVE into the expression it binds.
|
|
Visit(OVE->getSourceExpr());
|
|
else
|
|
Visit(S);
|
|
}
|
|
}
|
|
|
|
bool FoundDeclInUse() { return FoundDecl; }
|
|
|
|
}; // end class DeclMatcher
|
|
|
|
void CheckForLoopConditionalStatement(Sema &S, Expr *Second,
|
|
Expr *Third, Stmt *Body) {
|
|
// Condition is empty
|
|
if (!Second) return;
|
|
|
|
if (S.Diags.isIgnored(diag::warn_variables_not_in_loop_body,
|
|
Second->getLocStart()))
|
|
return;
|
|
|
|
PartialDiagnostic PDiag = S.PDiag(diag::warn_variables_not_in_loop_body);
|
|
llvm::SmallPtrSet<VarDecl*, 8> Decls;
|
|
SmallVector<SourceRange, 10> Ranges;
|
|
DeclExtractor DE(S, Decls, Ranges);
|
|
DE.Visit(Second);
|
|
|
|
// Don't analyze complex conditionals.
|
|
if (!DE.isSimple()) return;
|
|
|
|
// No decls found.
|
|
if (Decls.size() == 0) return;
|
|
|
|
// Don't warn on volatile, static, or global variables.
|
|
for (llvm::SmallPtrSetImpl<VarDecl*>::iterator I = Decls.begin(),
|
|
E = Decls.end();
|
|
I != E; ++I)
|
|
if ((*I)->getType().isVolatileQualified() ||
|
|
(*I)->hasGlobalStorage()) return;
|
|
|
|
if (DeclMatcher(S, Decls, Second).FoundDeclInUse() ||
|
|
DeclMatcher(S, Decls, Third).FoundDeclInUse() ||
|
|
DeclMatcher(S, Decls, Body).FoundDeclInUse())
|
|
return;
|
|
|
|
// Load decl names into diagnostic.
|
|
if (Decls.size() > 4)
|
|
PDiag << 0;
|
|
else {
|
|
PDiag << Decls.size();
|
|
for (llvm::SmallPtrSetImpl<VarDecl*>::iterator I = Decls.begin(),
|
|
E = Decls.end();
|
|
I != E; ++I)
|
|
PDiag << (*I)->getDeclName();
|
|
}
|
|
|
|
// Load SourceRanges into diagnostic if there is room.
|
|
// Otherwise, load the SourceRange of the conditional expression.
|
|
if (Ranges.size() <= PartialDiagnostic::MaxArguments)
|
|
for (SmallVectorImpl<SourceRange>::iterator I = Ranges.begin(),
|
|
E = Ranges.end();
|
|
I != E; ++I)
|
|
PDiag << *I;
|
|
else
|
|
PDiag << Second->getSourceRange();
|
|
|
|
S.Diag(Ranges.begin()->getBegin(), PDiag);
|
|
}
|
|
|
|
// If Statement is an incemement or decrement, return true and sets the
|
|
// variables Increment and DRE.
|
|
bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment,
|
|
DeclRefExpr *&DRE) {
|
|
if (auto Cleanups = dyn_cast<ExprWithCleanups>(Statement))
|
|
if (!Cleanups->cleanupsHaveSideEffects())
|
|
Statement = Cleanups->getSubExpr();
|
|
|
|
if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) {
|
|
switch (UO->getOpcode()) {
|
|
default: return false;
|
|
case UO_PostInc:
|
|
case UO_PreInc:
|
|
Increment = true;
|
|
break;
|
|
case UO_PostDec:
|
|
case UO_PreDec:
|
|
Increment = false;
|
|
break;
|
|
}
|
|
DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr());
|
|
return DRE;
|
|
}
|
|
|
|
if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(Statement)) {
|
|
FunctionDecl *FD = Call->getDirectCallee();
|
|
if (!FD || !FD->isOverloadedOperator()) return false;
|
|
switch (FD->getOverloadedOperator()) {
|
|
default: return false;
|
|
case OO_PlusPlus:
|
|
Increment = true;
|
|
break;
|
|
case OO_MinusMinus:
|
|
Increment = false;
|
|
break;
|
|
}
|
|
DRE = dyn_cast<DeclRefExpr>(Call->getArg(0));
|
|
return DRE;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// A visitor to determine if a continue or break statement is a
|
|
// subexpression.
|
|
class BreakContinueFinder : public EvaluatedExprVisitor<BreakContinueFinder> {
|
|
SourceLocation BreakLoc;
|
|
SourceLocation ContinueLoc;
|
|
public:
|
|
BreakContinueFinder(Sema &S, Stmt* Body) :
|
|
Inherited(S.Context) {
|
|
Visit(Body);
|
|
}
|
|
|
|
typedef EvaluatedExprVisitor<BreakContinueFinder> Inherited;
|
|
|
|
void VisitContinueStmt(ContinueStmt* E) {
|
|
ContinueLoc = E->getContinueLoc();
|
|
}
|
|
|
|
void VisitBreakStmt(BreakStmt* E) {
|
|
BreakLoc = E->getBreakLoc();
|
|
}
|
|
|
|
bool ContinueFound() { return ContinueLoc.isValid(); }
|
|
bool BreakFound() { return BreakLoc.isValid(); }
|
|
SourceLocation GetContinueLoc() { return ContinueLoc; }
|
|
SourceLocation GetBreakLoc() { return BreakLoc; }
|
|
|
|
}; // end class BreakContinueFinder
|
|
|
|
// Emit a warning when a loop increment/decrement appears twice per loop
|
|
// iteration. The conditions which trigger this warning are:
|
|
// 1) The last statement in the loop body and the third expression in the
|
|
// for loop are both increment or both decrement of the same variable
|
|
// 2) No continue statements in the loop body.
|
|
void CheckForRedundantIteration(Sema &S, Expr *Third, Stmt *Body) {
|
|
// Return when there is nothing to check.
|
|
if (!Body || !Third) return;
|
|
|
|
if (S.Diags.isIgnored(diag::warn_redundant_loop_iteration,
|
|
Third->getLocStart()))
|
|
return;
|
|
|
|
// Get the last statement from the loop body.
|
|
CompoundStmt *CS = dyn_cast<CompoundStmt>(Body);
|
|
if (!CS || CS->body_empty()) return;
|
|
Stmt *LastStmt = CS->body_back();
|
|
if (!LastStmt) return;
|
|
|
|
bool LoopIncrement, LastIncrement;
|
|
DeclRefExpr *LoopDRE, *LastDRE;
|
|
|
|
if (!ProcessIterationStmt(S, Third, LoopIncrement, LoopDRE)) return;
|
|
if (!ProcessIterationStmt(S, LastStmt, LastIncrement, LastDRE)) return;
|
|
|
|
// Check that the two statements are both increments or both decrements
|
|
// on the same variable.
|
|
if (LoopIncrement != LastIncrement ||
|
|
LoopDRE->getDecl() != LastDRE->getDecl()) return;
|
|
|
|
if (BreakContinueFinder(S, Body).ContinueFound()) return;
|
|
|
|
S.Diag(LastDRE->getLocation(), diag::warn_redundant_loop_iteration)
|
|
<< LastDRE->getDecl() << LastIncrement;
|
|
S.Diag(LoopDRE->getLocation(), diag::note_loop_iteration_here)
|
|
<< LoopIncrement;
|
|
}
|
|
|
|
} // end namespace
|
|
|
|
|
|
void Sema::CheckBreakContinueBinding(Expr *E) {
|
|
if (!E || getLangOpts().CPlusPlus)
|
|
return;
|
|
BreakContinueFinder BCFinder(*this, E);
|
|
Scope *BreakParent = CurScope->getBreakParent();
|
|
if (BCFinder.BreakFound() && BreakParent) {
|
|
if (BreakParent->getFlags() & Scope::SwitchScope) {
|
|
Diag(BCFinder.GetBreakLoc(), diag::warn_break_binds_to_switch);
|
|
} else {
|
|
Diag(BCFinder.GetBreakLoc(), diag::warn_loop_ctrl_binds_to_inner)
|
|
<< "break";
|
|
}
|
|
} else if (BCFinder.ContinueFound() && CurScope->getContinueParent()) {
|
|
Diag(BCFinder.GetContinueLoc(), diag::warn_loop_ctrl_binds_to_inner)
|
|
<< "continue";
|
|
}
|
|
}
|
|
|
|
StmtResult Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
|
|
Stmt *First, ConditionResult Second,
|
|
FullExprArg third, SourceLocation RParenLoc,
|
|
Stmt *Body) {
|
|
if (Second.isInvalid())
|
|
return StmtError();
|
|
|
|
if (!getLangOpts().CPlusPlus) {
|
|
if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
|
|
// C99 6.8.5p3: The declaration part of a 'for' statement shall only
|
|
// declare identifiers for objects having storage class 'auto' or
|
|
// 'register'.
|
|
for (auto *DI : DS->decls()) {
|
|
VarDecl *VD = dyn_cast<VarDecl>(DI);
|
|
if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage())
|
|
VD = nullptr;
|
|
if (!VD) {
|
|
Diag(DI->getLocation(), diag::err_non_local_variable_decl_in_for);
|
|
DI->setInvalidDecl();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
CheckBreakContinueBinding(Second.get().second);
|
|
CheckBreakContinueBinding(third.get());
|
|
|
|
if (!Second.get().first)
|
|
CheckForLoopConditionalStatement(*this, Second.get().second, third.get(),
|
|
Body);
|
|
CheckForRedundantIteration(*this, third.get(), Body);
|
|
|
|
if (Second.get().second &&
|
|
!Diags.isIgnored(diag::warn_comma_operator,
|
|
Second.get().second->getExprLoc()))
|
|
CommaVisitor(*this).Visit(Second.get().second);
|
|
|
|
Expr *Third = third.release().getAs<Expr>();
|
|
|
|
DiagnoseUnusedExprResult(First);
|
|
DiagnoseUnusedExprResult(Third);
|
|
DiagnoseUnusedExprResult(Body);
|
|
|
|
if (isa<NullStmt>(Body))
|
|
getCurCompoundScope().setHasEmptyLoopBodies();
|
|
|
|
return new (Context)
|
|
ForStmt(Context, First, Second.get().second, Second.get().first, Third,
|
|
Body, ForLoc, LParenLoc, RParenLoc);
|
|
}
|
|
|
|
/// In an Objective C collection iteration statement:
|
|
/// for (x in y)
|
|
/// x can be an arbitrary l-value expression. Bind it up as a
|
|
/// full-expression.
|
|
StmtResult Sema::ActOnForEachLValueExpr(Expr *E) {
|
|
// Reduce placeholder expressions here. Note that this rejects the
|
|
// use of pseudo-object l-values in this position.
|
|
ExprResult result = CheckPlaceholderExpr(E);
|
|
if (result.isInvalid()) return StmtError();
|
|
E = result.get();
|
|
|
|
ExprResult FullExpr = ActOnFinishFullExpr(E);
|
|
if (FullExpr.isInvalid())
|
|
return StmtError();
|
|
return StmtResult(static_cast<Stmt*>(FullExpr.get()));
|
|
}
|
|
|
|
ExprResult
|
|
Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
|
|
if (!collection)
|
|
return ExprError();
|
|
|
|
ExprResult result = CorrectDelayedTyposInExpr(collection);
|
|
if (!result.isUsable())
|
|
return ExprError();
|
|
collection = result.get();
|
|
|
|
// Bail out early if we've got a type-dependent expression.
|
|
if (collection->isTypeDependent()) return collection;
|
|
|
|
// Perform normal l-value conversion.
|
|
result = DefaultFunctionArrayLvalueConversion(collection);
|
|
if (result.isInvalid())
|
|
return ExprError();
|
|
collection = result.get();
|
|
|
|
// The operand needs to have object-pointer type.
|
|
// TODO: should we do a contextual conversion?
|
|
const ObjCObjectPointerType *pointerType =
|
|
collection->getType()->getAs<ObjCObjectPointerType>();
|
|
if (!pointerType)
|
|
return Diag(forLoc, diag::err_collection_expr_type)
|
|
<< collection->getType() << collection->getSourceRange();
|
|
|
|
// Check that the operand provides
|
|
// - countByEnumeratingWithState:objects:count:
|
|
const ObjCObjectType *objectType = pointerType->getObjectType();
|
|
ObjCInterfaceDecl *iface = objectType->getInterface();
|
|
|
|
// If we have a forward-declared type, we can't do this check.
|
|
// Under ARC, it is an error not to have a forward-declared class.
|
|
if (iface &&
|
|
(getLangOpts().ObjCAutoRefCount
|
|
? RequireCompleteType(forLoc, QualType(objectType, 0),
|
|
diag::err_arc_collection_forward, collection)
|
|
: !isCompleteType(forLoc, QualType(objectType, 0)))) {
|
|
// Otherwise, if we have any useful type information, check that
|
|
// the type declares the appropriate method.
|
|
} else if (iface || !objectType->qual_empty()) {
|
|
IdentifierInfo *selectorIdents[] = {
|
|
&Context.Idents.get("countByEnumeratingWithState"),
|
|
&Context.Idents.get("objects"),
|
|
&Context.Idents.get("count")
|
|
};
|
|
Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]);
|
|
|
|
ObjCMethodDecl *method = nullptr;
|
|
|
|
// If there's an interface, look in both the public and private APIs.
|
|
if (iface) {
|
|
method = iface->lookupInstanceMethod(selector);
|
|
if (!method) method = iface->lookupPrivateMethod(selector);
|
|
}
|
|
|
|
// Also check protocol qualifiers.
|
|
if (!method)
|
|
method = LookupMethodInQualifiedType(selector, pointerType,
|
|
/*instance*/ true);
|
|
|
|
// If we didn't find it anywhere, give up.
|
|
if (!method) {
|
|
Diag(forLoc, diag::warn_collection_expr_type)
|
|
<< collection->getType() << selector << collection->getSourceRange();
|
|
}
|
|
|
|
// TODO: check for an incompatible signature?
|
|
}
|
|
|
|
// Wrap up any cleanups in the expression.
|
|
return collection;
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
|
|
Stmt *First, Expr *collection,
|
|
SourceLocation RParenLoc) {
|
|
getCurFunction()->setHasBranchProtectedScope();
|
|
|
|
ExprResult CollectionExprResult =
|
|
CheckObjCForCollectionOperand(ForLoc, collection);
|
|
|
|
if (First) {
|
|
QualType FirstType;
|
|
if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
|
|
if (!DS->isSingleDecl())
|
|
return StmtError(Diag((*DS->decl_begin())->getLocation(),
|
|
diag::err_toomany_element_decls));
|
|
|
|
VarDecl *D = dyn_cast<VarDecl>(DS->getSingleDecl());
|
|
if (!D || D->isInvalidDecl())
|
|
return StmtError();
|
|
|
|
FirstType = D->getType();
|
|
// C99 6.8.5p3: The declaration part of a 'for' statement shall only
|
|
// declare identifiers for objects having storage class 'auto' or
|
|
// 'register'.
|
|
if (!D->hasLocalStorage())
|
|
return StmtError(Diag(D->getLocation(),
|
|
diag::err_non_local_variable_decl_in_for));
|
|
|
|
// If the type contained 'auto', deduce the 'auto' to 'id'.
|
|
if (FirstType->getContainedAutoType()) {
|
|
OpaqueValueExpr OpaqueId(D->getLocation(), Context.getObjCIdType(),
|
|
VK_RValue);
|
|
Expr *DeducedInit = &OpaqueId;
|
|
if (DeduceAutoType(D->getTypeSourceInfo(), DeducedInit, FirstType) ==
|
|
DAR_Failed)
|
|
DiagnoseAutoDeductionFailure(D, DeducedInit);
|
|
if (FirstType.isNull()) {
|
|
D->setInvalidDecl();
|
|
return StmtError();
|
|
}
|
|
|
|
D->setType(FirstType);
|
|
|
|
if (!inTemplateInstantiation()) {
|
|
SourceLocation Loc =
|
|
D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
|
|
Diag(Loc, diag::warn_auto_var_is_id)
|
|
<< D->getDeclName();
|
|
}
|
|
}
|
|
|
|
} else {
|
|
Expr *FirstE = cast<Expr>(First);
|
|
if (!FirstE->isTypeDependent() && !FirstE->isLValue())
|
|
return StmtError(Diag(First->getLocStart(),
|
|
diag::err_selector_element_not_lvalue)
|
|
<< First->getSourceRange());
|
|
|
|
FirstType = static_cast<Expr*>(First)->getType();
|
|
if (FirstType.isConstQualified())
|
|
Diag(ForLoc, diag::err_selector_element_const_type)
|
|
<< FirstType << First->getSourceRange();
|
|
}
|
|
if (!FirstType->isDependentType() &&
|
|
!FirstType->isObjCObjectPointerType() &&
|
|
!FirstType->isBlockPointerType())
|
|
return StmtError(Diag(ForLoc, diag::err_selector_element_type)
|
|
<< FirstType << First->getSourceRange());
|
|
}
|
|
|
|
if (CollectionExprResult.isInvalid())
|
|
return StmtError();
|
|
|
|
CollectionExprResult = ActOnFinishFullExpr(CollectionExprResult.get());
|
|
if (CollectionExprResult.isInvalid())
|
|
return StmtError();
|
|
|
|
return new (Context) ObjCForCollectionStmt(First, CollectionExprResult.get(),
|
|
nullptr, ForLoc, RParenLoc);
|
|
}
|
|
|
|
/// Finish building a variable declaration for a for-range statement.
|
|
/// \return true if an error occurs.
|
|
static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init,
|
|
SourceLocation Loc, int DiagID) {
|
|
if (Decl->getType()->isUndeducedType()) {
|
|
ExprResult Res = SemaRef.CorrectDelayedTyposInExpr(Init);
|
|
if (!Res.isUsable()) {
|
|
Decl->setInvalidDecl();
|
|
return true;
|
|
}
|
|
Init = Res.get();
|
|
}
|
|
|
|
// Deduce the type for the iterator variable now rather than leaving it to
|
|
// AddInitializerToDecl, so we can produce a more suitable diagnostic.
|
|
QualType InitType;
|
|
if ((!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) ||
|
|
SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitType) ==
|
|
Sema::DAR_Failed)
|
|
SemaRef.Diag(Loc, DiagID) << Init->getType();
|
|
if (InitType.isNull()) {
|
|
Decl->setInvalidDecl();
|
|
return true;
|
|
}
|
|
Decl->setType(InitType);
|
|
|
|
// In ARC, infer lifetime.
|
|
// FIXME: ARC may want to turn this into 'const __unsafe_unretained' if
|
|
// we're doing the equivalent of fast iteration.
|
|
if (SemaRef.getLangOpts().ObjCAutoRefCount &&
|
|
SemaRef.inferObjCARCLifetime(Decl))
|
|
Decl->setInvalidDecl();
|
|
|
|
SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false);
|
|
SemaRef.FinalizeDeclaration(Decl);
|
|
SemaRef.CurContext->addHiddenDecl(Decl);
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
// An enum to represent whether something is dealing with a call to begin()
|
|
// or a call to end() in a range-based for loop.
|
|
enum BeginEndFunction {
|
|
BEF_begin,
|
|
BEF_end
|
|
};
|
|
|
|
/// Produce a note indicating which begin/end function was implicitly called
|
|
/// by a C++11 for-range statement. This is often not obvious from the code,
|
|
/// nor from the diagnostics produced when analysing the implicit expressions
|
|
/// required in a for-range statement.
|
|
void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E,
|
|
BeginEndFunction BEF) {
|
|
CallExpr *CE = dyn_cast<CallExpr>(E);
|
|
if (!CE)
|
|
return;
|
|
FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
|
|
if (!D)
|
|
return;
|
|
SourceLocation Loc = D->getLocation();
|
|
|
|
std::string Description;
|
|
bool IsTemplate = false;
|
|
if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) {
|
|
Description = SemaRef.getTemplateArgumentBindingsText(
|
|
FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs());
|
|
IsTemplate = true;
|
|
}
|
|
|
|
SemaRef.Diag(Loc, diag::note_for_range_begin_end)
|
|
<< BEF << IsTemplate << Description << E->getType();
|
|
}
|
|
|
|
/// Build a variable declaration for a for-range statement.
|
|
VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc,
|
|
QualType Type, const char *Name) {
|
|
DeclContext *DC = SemaRef.CurContext;
|
|
IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name);
|
|
TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc);
|
|
VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type,
|
|
TInfo, SC_None);
|
|
Decl->setImplicit();
|
|
return Decl;
|
|
}
|
|
|
|
}
|
|
|
|
static bool ObjCEnumerationCollection(Expr *Collection) {
|
|
return !Collection->isTypeDependent()
|
|
&& Collection->getType()->getAs<ObjCObjectPointerType>() != nullptr;
|
|
}
|
|
|
|
/// ActOnCXXForRangeStmt - Check and build a C++11 for-range statement.
|
|
///
|
|
/// C++11 [stmt.ranged]:
|
|
/// A range-based for statement is equivalent to
|
|
///
|
|
/// {
|
|
/// auto && __range = range-init;
|
|
/// for ( auto __begin = begin-expr,
|
|
/// __end = end-expr;
|
|
/// __begin != __end;
|
|
/// ++__begin ) {
|
|
/// for-range-declaration = *__begin;
|
|
/// statement
|
|
/// }
|
|
/// }
|
|
///
|
|
/// The body of the loop is not available yet, since it cannot be analysed until
|
|
/// we have determined the type of the for-range-declaration.
|
|
StmtResult Sema::ActOnCXXForRangeStmt(Scope *S, SourceLocation ForLoc,
|
|
SourceLocation CoawaitLoc, Stmt *First,
|
|
SourceLocation ColonLoc, Expr *Range,
|
|
SourceLocation RParenLoc,
|
|
BuildForRangeKind Kind) {
|
|
if (!First)
|
|
return StmtError();
|
|
|
|
if (Range && ObjCEnumerationCollection(Range))
|
|
return ActOnObjCForCollectionStmt(ForLoc, First, Range, RParenLoc);
|
|
|
|
DeclStmt *DS = dyn_cast<DeclStmt>(First);
|
|
assert(DS && "first part of for range not a decl stmt");
|
|
|
|
if (!DS->isSingleDecl()) {
|
|
Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range);
|
|
return StmtError();
|
|
}
|
|
|
|
Decl *LoopVar = DS->getSingleDecl();
|
|
if (LoopVar->isInvalidDecl() || !Range ||
|
|
DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) {
|
|
LoopVar->setInvalidDecl();
|
|
return StmtError();
|
|
}
|
|
|
|
// Coroutines: 'for co_await' implicitly co_awaits its range.
|
|
if (CoawaitLoc.isValid()) {
|
|
ExprResult Coawait = ActOnCoawaitExpr(S, CoawaitLoc, Range);
|
|
if (Coawait.isInvalid()) return StmtError();
|
|
Range = Coawait.get();
|
|
}
|
|
|
|
// Build auto && __range = range-init
|
|
SourceLocation RangeLoc = Range->getLocStart();
|
|
VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc,
|
|
Context.getAutoRRefDeductType(),
|
|
"__range");
|
|
if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc,
|
|
diag::err_for_range_deduction_failure)) {
|
|
LoopVar->setInvalidDecl();
|
|
return StmtError();
|
|
}
|
|
|
|
// Claim the type doesn't contain auto: we've already done the checking.
|
|
DeclGroupPtrTy RangeGroup =
|
|
BuildDeclaratorGroup(MutableArrayRef<Decl *>((Decl **)&RangeVar, 1));
|
|
StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
|
|
if (RangeDecl.isInvalid()) {
|
|
LoopVar->setInvalidDecl();
|
|
return StmtError();
|
|
}
|
|
|
|
return BuildCXXForRangeStmt(ForLoc, CoawaitLoc, ColonLoc, RangeDecl.get(),
|
|
/*BeginStmt=*/nullptr, /*EndStmt=*/nullptr,
|
|
/*Cond=*/nullptr, /*Inc=*/nullptr,
|
|
DS, RParenLoc, Kind);
|
|
}
|
|
|
|
/// \brief Create the initialization, compare, and increment steps for
|
|
/// the range-based for loop expression.
|
|
/// This function does not handle array-based for loops,
|
|
/// which are created in Sema::BuildCXXForRangeStmt.
|
|
///
|
|
/// \returns a ForRangeStatus indicating success or what kind of error occurred.
|
|
/// BeginExpr and EndExpr are set and FRS_Success is returned on success;
|
|
/// CandidateSet and BEF are set and some non-success value is returned on
|
|
/// failure.
|
|
static Sema::ForRangeStatus BuildNonArrayForRange(Sema &SemaRef,
|
|
Expr *BeginRange, Expr *EndRange,
|
|
QualType RangeType,
|
|
VarDecl *BeginVar,
|
|
VarDecl *EndVar,
|
|
SourceLocation ColonLoc,
|
|
OverloadCandidateSet *CandidateSet,
|
|
ExprResult *BeginExpr,
|
|
ExprResult *EndExpr,
|
|
BeginEndFunction *BEF) {
|
|
DeclarationNameInfo BeginNameInfo(
|
|
&SemaRef.PP.getIdentifierTable().get("begin"), ColonLoc);
|
|
DeclarationNameInfo EndNameInfo(&SemaRef.PP.getIdentifierTable().get("end"),
|
|
ColonLoc);
|
|
|
|
LookupResult BeginMemberLookup(SemaRef, BeginNameInfo,
|
|
Sema::LookupMemberName);
|
|
LookupResult EndMemberLookup(SemaRef, EndNameInfo, Sema::LookupMemberName);
|
|
|
|
if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) {
|
|
// - if _RangeT is a class type, the unqualified-ids begin and end are
|
|
// looked up in the scope of class _RangeT as if by class member access
|
|
// lookup (3.4.5), and if either (or both) finds at least one
|
|
// declaration, begin-expr and end-expr are __range.begin() and
|
|
// __range.end(), respectively;
|
|
SemaRef.LookupQualifiedName(BeginMemberLookup, D);
|
|
SemaRef.LookupQualifiedName(EndMemberLookup, D);
|
|
|
|
if (BeginMemberLookup.empty() != EndMemberLookup.empty()) {
|
|
SourceLocation RangeLoc = BeginVar->getLocation();
|
|
*BEF = BeginMemberLookup.empty() ? BEF_end : BEF_begin;
|
|
|
|
SemaRef.Diag(RangeLoc, diag::err_for_range_member_begin_end_mismatch)
|
|
<< RangeLoc << BeginRange->getType() << *BEF;
|
|
return Sema::FRS_DiagnosticIssued;
|
|
}
|
|
} else {
|
|
// - otherwise, begin-expr and end-expr are begin(__range) and
|
|
// end(__range), respectively, where begin and end are looked up with
|
|
// argument-dependent lookup (3.4.2). For the purposes of this name
|
|
// lookup, namespace std is an associated namespace.
|
|
|
|
}
|
|
|
|
*BEF = BEF_begin;
|
|
Sema::ForRangeStatus RangeStatus =
|
|
SemaRef.BuildForRangeBeginEndCall(ColonLoc, ColonLoc, BeginNameInfo,
|
|
BeginMemberLookup, CandidateSet,
|
|
BeginRange, BeginExpr);
|
|
|
|
if (RangeStatus != Sema::FRS_Success) {
|
|
if (RangeStatus == Sema::FRS_DiagnosticIssued)
|
|
SemaRef.Diag(BeginRange->getLocStart(), diag::note_in_for_range)
|
|
<< ColonLoc << BEF_begin << BeginRange->getType();
|
|
return RangeStatus;
|
|
}
|
|
if (FinishForRangeVarDecl(SemaRef, BeginVar, BeginExpr->get(), ColonLoc,
|
|
diag::err_for_range_iter_deduction_failure)) {
|
|
NoteForRangeBeginEndFunction(SemaRef, BeginExpr->get(), *BEF);
|
|
return Sema::FRS_DiagnosticIssued;
|
|
}
|
|
|
|
*BEF = BEF_end;
|
|
RangeStatus =
|
|
SemaRef.BuildForRangeBeginEndCall(ColonLoc, ColonLoc, EndNameInfo,
|
|
EndMemberLookup, CandidateSet,
|
|
EndRange, EndExpr);
|
|
if (RangeStatus != Sema::FRS_Success) {
|
|
if (RangeStatus == Sema::FRS_DiagnosticIssued)
|
|
SemaRef.Diag(EndRange->getLocStart(), diag::note_in_for_range)
|
|
<< ColonLoc << BEF_end << EndRange->getType();
|
|
return RangeStatus;
|
|
}
|
|
if (FinishForRangeVarDecl(SemaRef, EndVar, EndExpr->get(), ColonLoc,
|
|
diag::err_for_range_iter_deduction_failure)) {
|
|
NoteForRangeBeginEndFunction(SemaRef, EndExpr->get(), *BEF);
|
|
return Sema::FRS_DiagnosticIssued;
|
|
}
|
|
return Sema::FRS_Success;
|
|
}
|
|
|
|
/// Speculatively attempt to dereference an invalid range expression.
|
|
/// If the attempt fails, this function will return a valid, null StmtResult
|
|
/// and emit no diagnostics.
|
|
static StmtResult RebuildForRangeWithDereference(Sema &SemaRef, Scope *S,
|
|
SourceLocation ForLoc,
|
|
SourceLocation CoawaitLoc,
|
|
Stmt *LoopVarDecl,
|
|
SourceLocation ColonLoc,
|
|
Expr *Range,
|
|
SourceLocation RangeLoc,
|
|
SourceLocation RParenLoc) {
|
|
// Determine whether we can rebuild the for-range statement with a
|
|
// dereferenced range expression.
|
|
ExprResult AdjustedRange;
|
|
{
|
|
Sema::SFINAETrap Trap(SemaRef);
|
|
|
|
AdjustedRange = SemaRef.BuildUnaryOp(S, RangeLoc, UO_Deref, Range);
|
|
if (AdjustedRange.isInvalid())
|
|
return StmtResult();
|
|
|
|
StmtResult SR = SemaRef.ActOnCXXForRangeStmt(
|
|
S, ForLoc, CoawaitLoc, LoopVarDecl, ColonLoc, AdjustedRange.get(),
|
|
RParenLoc, Sema::BFRK_Check);
|
|
if (SR.isInvalid())
|
|
return StmtResult();
|
|
}
|
|
|
|
// The attempt to dereference worked well enough that it could produce a valid
|
|
// loop. Produce a fixit, and rebuild the loop with diagnostics enabled, in
|
|
// case there are any other (non-fatal) problems with it.
|
|
SemaRef.Diag(RangeLoc, diag::err_for_range_dereference)
|
|
<< Range->getType() << FixItHint::CreateInsertion(RangeLoc, "*");
|
|
return SemaRef.ActOnCXXForRangeStmt(S, ForLoc, CoawaitLoc, LoopVarDecl,
|
|
ColonLoc, AdjustedRange.get(), RParenLoc,
|
|
Sema::BFRK_Rebuild);
|
|
}
|
|
|
|
namespace {
|
|
/// RAII object to automatically invalidate a declaration if an error occurs.
|
|
struct InvalidateOnErrorScope {
|
|
InvalidateOnErrorScope(Sema &SemaRef, Decl *D, bool Enabled)
|
|
: Trap(SemaRef.Diags), D(D), Enabled(Enabled) {}
|
|
~InvalidateOnErrorScope() {
|
|
if (Enabled && Trap.hasErrorOccurred())
|
|
D->setInvalidDecl();
|
|
}
|
|
|
|
DiagnosticErrorTrap Trap;
|
|
Decl *D;
|
|
bool Enabled;
|
|
};
|
|
}
|
|
|
|
/// BuildCXXForRangeStmt - Build or instantiate a C++11 for-range statement.
|
|
StmtResult
|
|
Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation CoawaitLoc,
|
|
SourceLocation ColonLoc, Stmt *RangeDecl,
|
|
Stmt *Begin, Stmt *End, Expr *Cond,
|
|
Expr *Inc, Stmt *LoopVarDecl,
|
|
SourceLocation RParenLoc, BuildForRangeKind Kind) {
|
|
// FIXME: This should not be used during template instantiation. We should
|
|
// pick up the set of unqualified lookup results for the != and + operators
|
|
// in the initial parse.
|
|
//
|
|
// Testcase (accepts-invalid):
|
|
// template<typename T> void f() { for (auto x : T()) {} }
|
|
// namespace N { struct X { X begin(); X end(); int operator*(); }; }
|
|
// bool operator!=(N::X, N::X); void operator++(N::X);
|
|
// void g() { f<N::X>(); }
|
|
Scope *S = getCurScope();
|
|
|
|
DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl);
|
|
VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
|
|
QualType RangeVarType = RangeVar->getType();
|
|
|
|
DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl);
|
|
VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl());
|
|
|
|
// If we hit any errors, mark the loop variable as invalid if its type
|
|
// contains 'auto'.
|
|
InvalidateOnErrorScope Invalidate(*this, LoopVar,
|
|
LoopVar->getType()->isUndeducedType());
|
|
|
|
StmtResult BeginDeclStmt = Begin;
|
|
StmtResult EndDeclStmt = End;
|
|
ExprResult NotEqExpr = Cond, IncrExpr = Inc;
|
|
|
|
if (RangeVarType->isDependentType()) {
|
|
// The range is implicitly used as a placeholder when it is dependent.
|
|
RangeVar->markUsed(Context);
|
|
|
|
// Deduce any 'auto's in the loop variable as 'DependentTy'. We'll fill
|
|
// them in properly when we instantiate the loop.
|
|
if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check)
|
|
LoopVar->setType(SubstAutoType(LoopVar->getType(), Context.DependentTy));
|
|
} else if (!BeginDeclStmt.get()) {
|
|
SourceLocation RangeLoc = RangeVar->getLocation();
|
|
|
|
const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType();
|
|
|
|
ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
|
|
VK_LValue, ColonLoc);
|
|
if (BeginRangeRef.isInvalid())
|
|
return StmtError();
|
|
|
|
ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
|
|
VK_LValue, ColonLoc);
|
|
if (EndRangeRef.isInvalid())
|
|
return StmtError();
|
|
|
|
QualType AutoType = Context.getAutoDeductType();
|
|
Expr *Range = RangeVar->getInit();
|
|
if (!Range)
|
|
return StmtError();
|
|
QualType RangeType = Range->getType();
|
|
|
|
if (RequireCompleteType(RangeLoc, RangeType,
|
|
diag::err_for_range_incomplete_type))
|
|
return StmtError();
|
|
|
|
// Build auto __begin = begin-expr, __end = end-expr.
|
|
VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
|
|
"__begin");
|
|
VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
|
|
"__end");
|
|
|
|
// Build begin-expr and end-expr and attach to __begin and __end variables.
|
|
ExprResult BeginExpr, EndExpr;
|
|
if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) {
|
|
// - if _RangeT is an array type, begin-expr and end-expr are __range and
|
|
// __range + __bound, respectively, where __bound is the array bound. If
|
|
// _RangeT is an array of unknown size or an array of incomplete type,
|
|
// the program is ill-formed;
|
|
|
|
// begin-expr is __range.
|
|
BeginExpr = BeginRangeRef;
|
|
if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc,
|
|
diag::err_for_range_iter_deduction_failure)) {
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
return StmtError();
|
|
}
|
|
|
|
// Find the array bound.
|
|
ExprResult BoundExpr;
|
|
if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT))
|
|
BoundExpr = IntegerLiteral::Create(
|
|
Context, CAT->getSize(), Context.getPointerDiffType(), RangeLoc);
|
|
else if (const VariableArrayType *VAT =
|
|
dyn_cast<VariableArrayType>(UnqAT)) {
|
|
// For a variably modified type we can't just use the expression within
|
|
// the array bounds, since we don't want that to be re-evaluated here.
|
|
// Rather, we need to determine what it was when the array was first
|
|
// created - so we resort to using sizeof(vla)/sizeof(element).
|
|
// For e.g.
|
|
// void f(int b) {
|
|
// int vla[b];
|
|
// b = -1; <-- This should not affect the num of iterations below
|
|
// for (int &c : vla) { .. }
|
|
// }
|
|
|
|
// FIXME: This results in codegen generating IR that recalculates the
|
|
// run-time number of elements (as opposed to just using the IR Value
|
|
// that corresponds to the run-time value of each bound that was
|
|
// generated when the array was created.) If this proves too embarassing
|
|
// even for unoptimized IR, consider passing a magic-value/cookie to
|
|
// codegen that then knows to simply use that initial llvm::Value (that
|
|
// corresponds to the bound at time of array creation) within
|
|
// getelementptr. But be prepared to pay the price of increasing a
|
|
// customized form of coupling between the two components - which could
|
|
// be hard to maintain as the codebase evolves.
|
|
|
|
ExprResult SizeOfVLAExprR = ActOnUnaryExprOrTypeTraitExpr(
|
|
EndVar->getLocation(), UETT_SizeOf,
|
|
/*isType=*/true,
|
|
CreateParsedType(VAT->desugar(), Context.getTrivialTypeSourceInfo(
|
|
VAT->desugar(), RangeLoc))
|
|
.getAsOpaquePtr(),
|
|
EndVar->getSourceRange());
|
|
if (SizeOfVLAExprR.isInvalid())
|
|
return StmtError();
|
|
|
|
ExprResult SizeOfEachElementExprR = ActOnUnaryExprOrTypeTraitExpr(
|
|
EndVar->getLocation(), UETT_SizeOf,
|
|
/*isType=*/true,
|
|
CreateParsedType(VAT->desugar(),
|
|
Context.getTrivialTypeSourceInfo(
|
|
VAT->getElementType(), RangeLoc))
|
|
.getAsOpaquePtr(),
|
|
EndVar->getSourceRange());
|
|
if (SizeOfEachElementExprR.isInvalid())
|
|
return StmtError();
|
|
|
|
BoundExpr =
|
|
ActOnBinOp(S, EndVar->getLocation(), tok::slash,
|
|
SizeOfVLAExprR.get(), SizeOfEachElementExprR.get());
|
|
if (BoundExpr.isInvalid())
|
|
return StmtError();
|
|
|
|
} else {
|
|
// Can't be a DependentSizedArrayType or an IncompleteArrayType since
|
|
// UnqAT is not incomplete and Range is not type-dependent.
|
|
llvm_unreachable("Unexpected array type in for-range");
|
|
}
|
|
|
|
// end-expr is __range + __bound.
|
|
EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(),
|
|
BoundExpr.get());
|
|
if (EndExpr.isInvalid())
|
|
return StmtError();
|
|
if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc,
|
|
diag::err_for_range_iter_deduction_failure)) {
|
|
NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
|
|
return StmtError();
|
|
}
|
|
} else {
|
|
OverloadCandidateSet CandidateSet(RangeLoc,
|
|
OverloadCandidateSet::CSK_Normal);
|
|
BeginEndFunction BEFFailure;
|
|
ForRangeStatus RangeStatus =
|
|
BuildNonArrayForRange(*this, BeginRangeRef.get(),
|
|
EndRangeRef.get(), RangeType,
|
|
BeginVar, EndVar, ColonLoc, &CandidateSet,
|
|
&BeginExpr, &EndExpr, &BEFFailure);
|
|
|
|
if (Kind == BFRK_Build && RangeStatus == FRS_NoViableFunction &&
|
|
BEFFailure == BEF_begin) {
|
|
// If the range is being built from an array parameter, emit a
|
|
// a diagnostic that it is being treated as a pointer.
|
|
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Range)) {
|
|
if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
|
|
QualType ArrayTy = PVD->getOriginalType();
|
|
QualType PointerTy = PVD->getType();
|
|
if (PointerTy->isPointerType() && ArrayTy->isArrayType()) {
|
|
Diag(Range->getLocStart(), diag::err_range_on_array_parameter)
|
|
<< RangeLoc << PVD << ArrayTy << PointerTy;
|
|
Diag(PVD->getLocation(), diag::note_declared_at);
|
|
return StmtError();
|
|
}
|
|
}
|
|
}
|
|
|
|
// If building the range failed, try dereferencing the range expression
|
|
// unless a diagnostic was issued or the end function is problematic.
|
|
StmtResult SR = RebuildForRangeWithDereference(*this, S, ForLoc,
|
|
CoawaitLoc,
|
|
LoopVarDecl, ColonLoc,
|
|
Range, RangeLoc,
|
|
RParenLoc);
|
|
if (SR.isInvalid() || SR.isUsable())
|
|
return SR;
|
|
}
|
|
|
|
// Otherwise, emit diagnostics if we haven't already.
|
|
if (RangeStatus == FRS_NoViableFunction) {
|
|
Expr *Range = BEFFailure ? EndRangeRef.get() : BeginRangeRef.get();
|
|
Diag(Range->getLocStart(), diag::err_for_range_invalid)
|
|
<< RangeLoc << Range->getType() << BEFFailure;
|
|
CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Range);
|
|
}
|
|
// Return an error if no fix was discovered.
|
|
if (RangeStatus != FRS_Success)
|
|
return StmtError();
|
|
}
|
|
|
|
assert(!BeginExpr.isInvalid() && !EndExpr.isInvalid() &&
|
|
"invalid range expression in for loop");
|
|
|
|
// C++11 [dcl.spec.auto]p7: BeginType and EndType must be the same.
|
|
// C++1z removes this restriction.
|
|
QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
|
|
if (!Context.hasSameType(BeginType, EndType)) {
|
|
Diag(RangeLoc, getLangOpts().CPlusPlus1z
|
|
? diag::warn_for_range_begin_end_types_differ
|
|
: diag::ext_for_range_begin_end_types_differ)
|
|
<< BeginType << EndType;
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
|
|
}
|
|
|
|
BeginDeclStmt =
|
|
ActOnDeclStmt(ConvertDeclToDeclGroup(BeginVar), ColonLoc, ColonLoc);
|
|
EndDeclStmt =
|
|
ActOnDeclStmt(ConvertDeclToDeclGroup(EndVar), ColonLoc, ColonLoc);
|
|
|
|
const QualType BeginRefNonRefType = BeginType.getNonReferenceType();
|
|
ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
|
|
VK_LValue, ColonLoc);
|
|
if (BeginRef.isInvalid())
|
|
return StmtError();
|
|
|
|
ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(),
|
|
VK_LValue, ColonLoc);
|
|
if (EndRef.isInvalid())
|
|
return StmtError();
|
|
|
|
// Build and check __begin != __end expression.
|
|
NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal,
|
|
BeginRef.get(), EndRef.get());
|
|
if (!NotEqExpr.isInvalid())
|
|
NotEqExpr = CheckBooleanCondition(ColonLoc, NotEqExpr.get());
|
|
if (!NotEqExpr.isInvalid())
|
|
NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get());
|
|
if (NotEqExpr.isInvalid()) {
|
|
Diag(RangeLoc, diag::note_for_range_invalid_iterator)
|
|
<< RangeLoc << 0 << BeginRangeRef.get()->getType();
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
if (!Context.hasSameType(BeginType, EndType))
|
|
NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
|
|
return StmtError();
|
|
}
|
|
|
|
// Build and check ++__begin expression.
|
|
BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
|
|
VK_LValue, ColonLoc);
|
|
if (BeginRef.isInvalid())
|
|
return StmtError();
|
|
|
|
IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get());
|
|
if (!IncrExpr.isInvalid() && CoawaitLoc.isValid())
|
|
IncrExpr = ActOnCoawaitExpr(S, CoawaitLoc, IncrExpr.get());
|
|
if (!IncrExpr.isInvalid())
|
|
IncrExpr = ActOnFinishFullExpr(IncrExpr.get());
|
|
if (IncrExpr.isInvalid()) {
|
|
Diag(RangeLoc, diag::note_for_range_invalid_iterator)
|
|
<< RangeLoc << 2 << BeginRangeRef.get()->getType() ;
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
return StmtError();
|
|
}
|
|
|
|
// Build and check *__begin expression.
|
|
BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
|
|
VK_LValue, ColonLoc);
|
|
if (BeginRef.isInvalid())
|
|
return StmtError();
|
|
|
|
ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get());
|
|
if (DerefExpr.isInvalid()) {
|
|
Diag(RangeLoc, diag::note_for_range_invalid_iterator)
|
|
<< RangeLoc << 1 << BeginRangeRef.get()->getType();
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
return StmtError();
|
|
}
|
|
|
|
// Attach *__begin as initializer for VD. Don't touch it if we're just
|
|
// trying to determine whether this would be a valid range.
|
|
if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) {
|
|
AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false);
|
|
if (LoopVar->isInvalidDecl())
|
|
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
|
|
}
|
|
}
|
|
|
|
// Don't bother to actually allocate the result if we're just trying to
|
|
// determine whether it would be valid.
|
|
if (Kind == BFRK_Check)
|
|
return StmtResult();
|
|
|
|
return new (Context) CXXForRangeStmt(
|
|
RangeDS, cast_or_null<DeclStmt>(BeginDeclStmt.get()),
|
|
cast_or_null<DeclStmt>(EndDeclStmt.get()), NotEqExpr.get(),
|
|
IncrExpr.get(), LoopVarDS, /*Body=*/nullptr, ForLoc, CoawaitLoc,
|
|
ColonLoc, RParenLoc);
|
|
}
|
|
|
|
/// FinishObjCForCollectionStmt - Attach the body to a objective-C foreach
|
|
/// statement.
|
|
StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) {
|
|
if (!S || !B)
|
|
return StmtError();
|
|
ObjCForCollectionStmt * ForStmt = cast<ObjCForCollectionStmt>(S);
|
|
|
|
ForStmt->setBody(B);
|
|
return S;
|
|
}
|
|
|
|
// Warn when the loop variable is a const reference that creates a copy.
|
|
// Suggest using the non-reference type for copies. If a copy can be prevented
|
|
// suggest the const reference type that would do so.
|
|
// For instance, given "for (const &Foo : Range)", suggest
|
|
// "for (const Foo : Range)" to denote a copy is made for the loop. If
|
|
// possible, also suggest "for (const &Bar : Range)" if this type prevents
|
|
// the copy altogether.
|
|
static void DiagnoseForRangeReferenceVariableCopies(Sema &SemaRef,
|
|
const VarDecl *VD,
|
|
QualType RangeInitType) {
|
|
const Expr *InitExpr = VD->getInit();
|
|
if (!InitExpr)
|
|
return;
|
|
|
|
QualType VariableType = VD->getType();
|
|
|
|
if (auto Cleanups = dyn_cast<ExprWithCleanups>(InitExpr))
|
|
if (!Cleanups->cleanupsHaveSideEffects())
|
|
InitExpr = Cleanups->getSubExpr();
|
|
|
|
const MaterializeTemporaryExpr *MTE =
|
|
dyn_cast<MaterializeTemporaryExpr>(InitExpr);
|
|
|
|
// No copy made.
|
|
if (!MTE)
|
|
return;
|
|
|
|
const Expr *E = MTE->GetTemporaryExpr()->IgnoreImpCasts();
|
|
|
|
// Searching for either UnaryOperator for dereference of a pointer or
|
|
// CXXOperatorCallExpr for handling iterators.
|
|
while (!isa<CXXOperatorCallExpr>(E) && !isa<UnaryOperator>(E)) {
|
|
if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(E)) {
|
|
E = CCE->getArg(0);
|
|
} else if (const CXXMemberCallExpr *Call = dyn_cast<CXXMemberCallExpr>(E)) {
|
|
const MemberExpr *ME = cast<MemberExpr>(Call->getCallee());
|
|
E = ME->getBase();
|
|
} else {
|
|
const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(E);
|
|
E = MTE->GetTemporaryExpr();
|
|
}
|
|
E = E->IgnoreImpCasts();
|
|
}
|
|
|
|
bool ReturnsReference = false;
|
|
if (isa<UnaryOperator>(E)) {
|
|
ReturnsReference = true;
|
|
} else {
|
|
const CXXOperatorCallExpr *Call = cast<CXXOperatorCallExpr>(E);
|
|
const FunctionDecl *FD = Call->getDirectCallee();
|
|
QualType ReturnType = FD->getReturnType();
|
|
ReturnsReference = ReturnType->isReferenceType();
|
|
}
|
|
|
|
if (ReturnsReference) {
|
|
// Loop variable creates a temporary. Suggest either to go with
|
|
// non-reference loop variable to indiciate a copy is made, or
|
|
// the correct time to bind a const reference.
|
|
SemaRef.Diag(VD->getLocation(), diag::warn_for_range_const_reference_copy)
|
|
<< VD << VariableType << E->getType();
|
|
QualType NonReferenceType = VariableType.getNonReferenceType();
|
|
NonReferenceType.removeLocalConst();
|
|
QualType NewReferenceType =
|
|
SemaRef.Context.getLValueReferenceType(E->getType().withConst());
|
|
SemaRef.Diag(VD->getLocStart(), diag::note_use_type_or_non_reference)
|
|
<< NonReferenceType << NewReferenceType << VD->getSourceRange();
|
|
} else {
|
|
// The range always returns a copy, so a temporary is always created.
|
|
// Suggest removing the reference from the loop variable.
|
|
SemaRef.Diag(VD->getLocation(), diag::warn_for_range_variable_always_copy)
|
|
<< VD << RangeInitType;
|
|
QualType NonReferenceType = VariableType.getNonReferenceType();
|
|
NonReferenceType.removeLocalConst();
|
|
SemaRef.Diag(VD->getLocStart(), diag::note_use_non_reference_type)
|
|
<< NonReferenceType << VD->getSourceRange();
|
|
}
|
|
}
|
|
|
|
// Warns when the loop variable can be changed to a reference type to
|
|
// prevent a copy. For instance, if given "for (const Foo x : Range)" suggest
|
|
// "for (const Foo &x : Range)" if this form does not make a copy.
|
|
static void DiagnoseForRangeConstVariableCopies(Sema &SemaRef,
|
|
const VarDecl *VD) {
|
|
const Expr *InitExpr = VD->getInit();
|
|
if (!InitExpr)
|
|
return;
|
|
|
|
QualType VariableType = VD->getType();
|
|
|
|
if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(InitExpr)) {
|
|
if (!CE->getConstructor()->isCopyConstructor())
|
|
return;
|
|
} else if (const CastExpr *CE = dyn_cast<CastExpr>(InitExpr)) {
|
|
if (CE->getCastKind() != CK_LValueToRValue)
|
|
return;
|
|
} else {
|
|
return;
|
|
}
|
|
|
|
// TODO: Determine a maximum size that a POD type can be before a diagnostic
|
|
// should be emitted. Also, only ignore POD types with trivial copy
|
|
// constructors.
|
|
if (VariableType.isPODType(SemaRef.Context))
|
|
return;
|
|
|
|
// Suggest changing from a const variable to a const reference variable
|
|
// if doing so will prevent a copy.
|
|
SemaRef.Diag(VD->getLocation(), diag::warn_for_range_copy)
|
|
<< VD << VariableType << InitExpr->getType();
|
|
SemaRef.Diag(VD->getLocStart(), diag::note_use_reference_type)
|
|
<< SemaRef.Context.getLValueReferenceType(VariableType)
|
|
<< VD->getSourceRange();
|
|
}
|
|
|
|
/// DiagnoseForRangeVariableCopies - Diagnose three cases and fixes for them.
|
|
/// 1) for (const foo &x : foos) where foos only returns a copy. Suggest
|
|
/// using "const foo x" to show that a copy is made
|
|
/// 2) for (const bar &x : foos) where bar is a temporary intialized by bar.
|
|
/// Suggest either "const bar x" to keep the copying or "const foo& x" to
|
|
/// prevent the copy.
|
|
/// 3) for (const foo x : foos) where x is constructed from a reference foo.
|
|
/// Suggest "const foo &x" to prevent the copy.
|
|
static void DiagnoseForRangeVariableCopies(Sema &SemaRef,
|
|
const CXXForRangeStmt *ForStmt) {
|
|
if (SemaRef.Diags.isIgnored(diag::warn_for_range_const_reference_copy,
|
|
ForStmt->getLocStart()) &&
|
|
SemaRef.Diags.isIgnored(diag::warn_for_range_variable_always_copy,
|
|
ForStmt->getLocStart()) &&
|
|
SemaRef.Diags.isIgnored(diag::warn_for_range_copy,
|
|
ForStmt->getLocStart())) {
|
|
return;
|
|
}
|
|
|
|
const VarDecl *VD = ForStmt->getLoopVariable();
|
|
if (!VD)
|
|
return;
|
|
|
|
QualType VariableType = VD->getType();
|
|
|
|
if (VariableType->isIncompleteType())
|
|
return;
|
|
|
|
const Expr *InitExpr = VD->getInit();
|
|
if (!InitExpr)
|
|
return;
|
|
|
|
if (VariableType->isReferenceType()) {
|
|
DiagnoseForRangeReferenceVariableCopies(SemaRef, VD,
|
|
ForStmt->getRangeInit()->getType());
|
|
} else if (VariableType.isConstQualified()) {
|
|
DiagnoseForRangeConstVariableCopies(SemaRef, VD);
|
|
}
|
|
}
|
|
|
|
/// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement.
|
|
/// This is a separate step from ActOnCXXForRangeStmt because analysis of the
|
|
/// body cannot be performed until after the type of the range variable is
|
|
/// determined.
|
|
StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) {
|
|
if (!S || !B)
|
|
return StmtError();
|
|
|
|
if (isa<ObjCForCollectionStmt>(S))
|
|
return FinishObjCForCollectionStmt(S, B);
|
|
|
|
CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
|
|
ForStmt->setBody(B);
|
|
|
|
DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B,
|
|
diag::warn_empty_range_based_for_body);
|
|
|
|
DiagnoseForRangeVariableCopies(*this, ForStmt);
|
|
|
|
return S;
|
|
}
|
|
|
|
StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
|
|
SourceLocation LabelLoc,
|
|
LabelDecl *TheDecl) {
|
|
getCurFunction()->setHasBranchIntoScope();
|
|
TheDecl->markUsed(Context);
|
|
return new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
|
|
Expr *E) {
|
|
// Convert operand to void*
|
|
if (!E->isTypeDependent()) {
|
|
QualType ETy = E->getType();
|
|
QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
|
|
ExprResult ExprRes = E;
|
|
AssignConvertType ConvTy =
|
|
CheckSingleAssignmentConstraints(DestTy, ExprRes);
|
|
if (ExprRes.isInvalid())
|
|
return StmtError();
|
|
E = ExprRes.get();
|
|
if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
|
|
return StmtError();
|
|
}
|
|
|
|
ExprResult ExprRes = ActOnFinishFullExpr(E);
|
|
if (ExprRes.isInvalid())
|
|
return StmtError();
|
|
E = ExprRes.get();
|
|
|
|
getCurFunction()->setHasIndirectGoto();
|
|
|
|
return new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E);
|
|
}
|
|
|
|
static void CheckJumpOutOfSEHFinally(Sema &S, SourceLocation Loc,
|
|
const Scope &DestScope) {
|
|
if (!S.CurrentSEHFinally.empty() &&
|
|
DestScope.Contains(*S.CurrentSEHFinally.back())) {
|
|
S.Diag(Loc, diag::warn_jump_out_of_seh_finally);
|
|
}
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
|
|
Scope *S = CurScope->getContinueParent();
|
|
if (!S) {
|
|
// C99 6.8.6.2p1: A break shall appear only in or as a loop body.
|
|
return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
|
|
}
|
|
CheckJumpOutOfSEHFinally(*this, ContinueLoc, *S);
|
|
|
|
return new (Context) ContinueStmt(ContinueLoc);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
|
|
Scope *S = CurScope->getBreakParent();
|
|
if (!S) {
|
|
// C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
|
|
return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
|
|
}
|
|
if (S->isOpenMPLoopScope())
|
|
return StmtError(Diag(BreakLoc, diag::err_omp_loop_cannot_use_stmt)
|
|
<< "break");
|
|
CheckJumpOutOfSEHFinally(*this, BreakLoc, *S);
|
|
|
|
return new (Context) BreakStmt(BreakLoc);
|
|
}
|
|
|
|
/// \brief Determine whether the given expression is a candidate for
|
|
/// copy elision in either a return statement or a throw expression.
|
|
///
|
|
/// \param ReturnType If we're determining the copy elision candidate for
|
|
/// a return statement, this is the return type of the function. If we're
|
|
/// determining the copy elision candidate for a throw expression, this will
|
|
/// be a NULL type.
|
|
///
|
|
/// \param E The expression being returned from the function or block, or
|
|
/// being thrown.
|
|
///
|
|
/// \param AllowParamOrMoveConstructible Whether we allow function parameters or
|
|
/// id-expressions that could be moved out of the function to be considered NRVO
|
|
/// candidates. C++ prohibits these for NRVO itself, but we re-use this logic to
|
|
/// determine whether we should try to move as part of a return or throw (which
|
|
/// does allow function parameters).
|
|
///
|
|
/// \returns The NRVO candidate variable, if the return statement may use the
|
|
/// NRVO, or NULL if there is no such candidate.
|
|
VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType, Expr *E,
|
|
bool AllowParamOrMoveConstructible) {
|
|
if (!getLangOpts().CPlusPlus)
|
|
return nullptr;
|
|
|
|
// - in a return statement in a function [where] ...
|
|
// ... the expression is the name of a non-volatile automatic object ...
|
|
DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
|
|
if (!DR || DR->refersToEnclosingVariableOrCapture())
|
|
return nullptr;
|
|
VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
|
|
if (!VD)
|
|
return nullptr;
|
|
|
|
if (isCopyElisionCandidate(ReturnType, VD, AllowParamOrMoveConstructible))
|
|
return VD;
|
|
return nullptr;
|
|
}
|
|
|
|
bool Sema::isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD,
|
|
bool AllowParamOrMoveConstructible) {
|
|
QualType VDType = VD->getType();
|
|
// - in a return statement in a function with ...
|
|
// ... a class return type ...
|
|
if (!ReturnType.isNull() && !ReturnType->isDependentType()) {
|
|
if (!ReturnType->isRecordType())
|
|
return false;
|
|
// ... the same cv-unqualified type as the function return type ...
|
|
// When considering moving this expression out, allow dissimilar types.
|
|
if (!AllowParamOrMoveConstructible && !VDType->isDependentType() &&
|
|
!Context.hasSameUnqualifiedType(ReturnType, VDType))
|
|
return false;
|
|
}
|
|
|
|
// ...object (other than a function or catch-clause parameter)...
|
|
if (VD->getKind() != Decl::Var &&
|
|
!(AllowParamOrMoveConstructible && VD->getKind() == Decl::ParmVar))
|
|
return false;
|
|
if (VD->isExceptionVariable()) return false;
|
|
|
|
// ...automatic...
|
|
if (!VD->hasLocalStorage()) return false;
|
|
|
|
// Return false if VD is a __block variable. We don't want to implicitly move
|
|
// out of a __block variable during a return because we cannot assume the
|
|
// variable will no longer be used.
|
|
if (VD->hasAttr<BlocksAttr>()) return false;
|
|
|
|
if (AllowParamOrMoveConstructible)
|
|
return true;
|
|
|
|
// ...non-volatile...
|
|
if (VD->getType().isVolatileQualified()) return false;
|
|
|
|
// Variables with higher required alignment than their type's ABI
|
|
// alignment cannot use NRVO.
|
|
if (!VD->getType()->isDependentType() && VD->hasAttr<AlignedAttr>() &&
|
|
Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType()))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/// \brief Perform the initialization of a potentially-movable value, which
|
|
/// is the result of return value.
|
|
///
|
|
/// This routine implements C++14 [class.copy]p32, which attempts to treat
|
|
/// returned lvalues as rvalues in certain cases (to prefer move construction),
|
|
/// then falls back to treating them as lvalues if that failed.
|
|
ExprResult
|
|
Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
|
|
const VarDecl *NRVOCandidate,
|
|
QualType ResultType,
|
|
Expr *Value,
|
|
bool AllowNRVO) {
|
|
// C++14 [class.copy]p32:
|
|
// When the criteria for elision of a copy/move operation are met, but not for
|
|
// an exception-declaration, and the object to be copied is designated by an
|
|
// lvalue, or when the expression in a return statement is a (possibly
|
|
// parenthesized) id-expression that names an object with automatic storage
|
|
// duration declared in the body or parameter-declaration-clause of the
|
|
// innermost enclosing function or lambda-expression, overload resolution to
|
|
// select the constructor for the copy is first performed as if the object
|
|
// were designated by an rvalue.
|
|
ExprResult Res = ExprError();
|
|
|
|
if (AllowNRVO && !NRVOCandidate)
|
|
NRVOCandidate = getCopyElisionCandidate(ResultType, Value, true);
|
|
|
|
if (AllowNRVO && NRVOCandidate) {
|
|
ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack, Value->getType(),
|
|
CK_NoOp, Value, VK_XValue);
|
|
|
|
Expr *InitExpr = &AsRvalue;
|
|
|
|
InitializationKind Kind = InitializationKind::CreateCopy(
|
|
Value->getLocStart(), Value->getLocStart());
|
|
|
|
InitializationSequence Seq(*this, Entity, Kind, InitExpr);
|
|
if (Seq) {
|
|
for (const InitializationSequence::Step &Step : Seq.steps()) {
|
|
if (!(Step.Kind ==
|
|
InitializationSequence::SK_ConstructorInitialization ||
|
|
(Step.Kind == InitializationSequence::SK_UserConversion &&
|
|
isa<CXXConstructorDecl>(Step.Function.Function))))
|
|
continue;
|
|
|
|
CXXConstructorDecl *Constructor =
|
|
cast<CXXConstructorDecl>(Step.Function.Function);
|
|
|
|
const RValueReferenceType *RRefType
|
|
= Constructor->getParamDecl(0)->getType()
|
|
->getAs<RValueReferenceType>();
|
|
|
|
// [...] If the first overload resolution fails or was not performed, or
|
|
// if the type of the first parameter of the selected constructor is not
|
|
// an rvalue reference to the object's type (possibly cv-qualified),
|
|
// overload resolution is performed again, considering the object as an
|
|
// lvalue.
|
|
if (!RRefType ||
|
|
!Context.hasSameUnqualifiedType(RRefType->getPointeeType(),
|
|
NRVOCandidate->getType()))
|
|
break;
|
|
|
|
// Promote "AsRvalue" to the heap, since we now need this
|
|
// expression node to persist.
|
|
Value = ImplicitCastExpr::Create(Context, Value->getType(), CK_NoOp,
|
|
Value, nullptr, VK_XValue);
|
|
|
|
// Complete type-checking the initialization of the return type
|
|
// using the constructor we found.
|
|
Res = Seq.Perform(*this, Entity, Kind, Value);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Either we didn't meet the criteria for treating an lvalue as an rvalue,
|
|
// above, or overload resolution failed. Either way, we need to try
|
|
// (again) now with the return value expression as written.
|
|
if (Res.isInvalid())
|
|
Res = PerformCopyInitialization(Entity, SourceLocation(), Value);
|
|
|
|
return Res;
|
|
}
|
|
|
|
/// \brief Determine whether the declared return type of the specified function
|
|
/// contains 'auto'.
|
|
static bool hasDeducedReturnType(FunctionDecl *FD) {
|
|
const FunctionProtoType *FPT =
|
|
FD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
|
|
return FPT->getReturnType()->isUndeducedType();
|
|
}
|
|
|
|
/// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
|
|
/// for capturing scopes.
|
|
///
|
|
StmtResult
|
|
Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
|
|
// If this is the first return we've seen, infer the return type.
|
|
// [expr.prim.lambda]p4 in C++11; block literals follow the same rules.
|
|
CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
|
|
QualType FnRetType = CurCap->ReturnType;
|
|
LambdaScopeInfo *CurLambda = dyn_cast<LambdaScopeInfo>(CurCap);
|
|
bool HasDeducedReturnType =
|
|
CurLambda && hasDeducedReturnType(CurLambda->CallOperator);
|
|
|
|
if (ExprEvalContexts.back().Context ==
|
|
ExpressionEvaluationContext::DiscardedStatement &&
|
|
(HasDeducedReturnType || CurCap->HasImplicitReturnType)) {
|
|
if (RetValExp) {
|
|
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
|
|
if (ER.isInvalid())
|
|
return StmtError();
|
|
RetValExp = ER.get();
|
|
}
|
|
return new (Context) ReturnStmt(ReturnLoc, RetValExp, nullptr);
|
|
}
|
|
|
|
if (HasDeducedReturnType) {
|
|
// In C++1y, the return type may involve 'auto'.
|
|
// FIXME: Blocks might have a return type of 'auto' explicitly specified.
|
|
FunctionDecl *FD = CurLambda->CallOperator;
|
|
if (CurCap->ReturnType.isNull())
|
|
CurCap->ReturnType = FD->getReturnType();
|
|
|
|
AutoType *AT = CurCap->ReturnType->getContainedAutoType();
|
|
assert(AT && "lost auto type from lambda return type");
|
|
if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
|
|
FD->setInvalidDecl();
|
|
return StmtError();
|
|
}
|
|
CurCap->ReturnType = FnRetType = FD->getReturnType();
|
|
} else if (CurCap->HasImplicitReturnType) {
|
|
// For blocks/lambdas with implicit return types, we check each return
|
|
// statement individually, and deduce the common return type when the block
|
|
// or lambda is completed.
|
|
// FIXME: Fold this into the 'auto' codepath above.
|
|
if (RetValExp && !isa<InitListExpr>(RetValExp)) {
|
|
ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
|
|
if (Result.isInvalid())
|
|
return StmtError();
|
|
RetValExp = Result.get();
|
|
|
|
// DR1048: even prior to C++14, we should use the 'auto' deduction rules
|
|
// when deducing a return type for a lambda-expression (or by extension
|
|
// for a block). These rules differ from the stated C++11 rules only in
|
|
// that they remove top-level cv-qualifiers.
|
|
if (!CurContext->isDependentContext())
|
|
FnRetType = RetValExp->getType().getUnqualifiedType();
|
|
else
|
|
FnRetType = CurCap->ReturnType = Context.DependentTy;
|
|
} else {
|
|
if (RetValExp) {
|
|
// C++11 [expr.lambda.prim]p4 bans inferring the result from an
|
|
// initializer list, because it is not an expression (even
|
|
// though we represent it as one). We still deduce 'void'.
|
|
Diag(ReturnLoc, diag::err_lambda_return_init_list)
|
|
<< RetValExp->getSourceRange();
|
|
}
|
|
|
|
FnRetType = Context.VoidTy;
|
|
}
|
|
|
|
// Although we'll properly infer the type of the block once it's completed,
|
|
// make sure we provide a return type now for better error recovery.
|
|
if (CurCap->ReturnType.isNull())
|
|
CurCap->ReturnType = FnRetType;
|
|
}
|
|
assert(!FnRetType.isNull());
|
|
|
|
if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) {
|
|
if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
|
|
Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
|
|
return StmtError();
|
|
}
|
|
} else if (CapturedRegionScopeInfo *CurRegion =
|
|
dyn_cast<CapturedRegionScopeInfo>(CurCap)) {
|
|
Diag(ReturnLoc, diag::err_return_in_captured_stmt) << CurRegion->getRegionName();
|
|
return StmtError();
|
|
} else {
|
|
assert(CurLambda && "unknown kind of captured scope");
|
|
if (CurLambda->CallOperator->getType()->getAs<FunctionType>()
|
|
->getNoReturnAttr()) {
|
|
Diag(ReturnLoc, diag::err_noreturn_lambda_has_return_expr);
|
|
return StmtError();
|
|
}
|
|
}
|
|
|
|
// Otherwise, verify that this result type matches the previous one. We are
|
|
// pickier with blocks than for normal functions because we don't have GCC
|
|
// compatibility to worry about here.
|
|
const VarDecl *NRVOCandidate = nullptr;
|
|
if (FnRetType->isDependentType()) {
|
|
// Delay processing for now. TODO: there are lots of dependent
|
|
// types we can conclusively prove aren't void.
|
|
} else if (FnRetType->isVoidType()) {
|
|
if (RetValExp && !isa<InitListExpr>(RetValExp) &&
|
|
!(getLangOpts().CPlusPlus &&
|
|
(RetValExp->isTypeDependent() ||
|
|
RetValExp->getType()->isVoidType()))) {
|
|
if (!getLangOpts().CPlusPlus &&
|
|
RetValExp->getType()->isVoidType())
|
|
Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2;
|
|
else {
|
|
Diag(ReturnLoc, diag::err_return_block_has_expr);
|
|
RetValExp = nullptr;
|
|
}
|
|
}
|
|
} else if (!RetValExp) {
|
|
return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
|
|
} else if (!RetValExp->isTypeDependent()) {
|
|
// we have a non-void block with an expression, continue checking
|
|
|
|
// C99 6.8.6.4p3(136): The return statement is not an assignment. The
|
|
// overlap restriction of subclause 6.5.16.1 does not apply to the case of
|
|
// function return.
|
|
|
|
// In C++ the return statement is handled via a copy initialization.
|
|
// the C version of which boils down to CheckSingleAssignmentConstraints.
|
|
NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
|
|
InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
|
|
FnRetType,
|
|
NRVOCandidate != nullptr);
|
|
ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
|
|
FnRetType, RetValExp);
|
|
if (Res.isInvalid()) {
|
|
// FIXME: Cleanup temporaries here, anyway?
|
|
return StmtError();
|
|
}
|
|
RetValExp = Res.get();
|
|
CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc);
|
|
} else {
|
|
NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
|
|
}
|
|
|
|
if (RetValExp) {
|
|
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
|
|
if (ER.isInvalid())
|
|
return StmtError();
|
|
RetValExp = ER.get();
|
|
}
|
|
ReturnStmt *Result = new (Context) ReturnStmt(ReturnLoc, RetValExp,
|
|
NRVOCandidate);
|
|
|
|
// If we need to check for the named return value optimization,
|
|
// or if we need to infer the return type,
|
|
// save the return statement in our scope for later processing.
|
|
if (CurCap->HasImplicitReturnType || NRVOCandidate)
|
|
FunctionScopes.back()->Returns.push_back(Result);
|
|
|
|
if (FunctionScopes.back()->FirstReturnLoc.isInvalid())
|
|
FunctionScopes.back()->FirstReturnLoc = ReturnLoc;
|
|
|
|
return Result;
|
|
}
|
|
|
|
namespace {
|
|
/// \brief Marks all typedefs in all local classes in a type referenced.
|
|
///
|
|
/// In a function like
|
|
/// auto f() {
|
|
/// struct S { typedef int a; };
|
|
/// return S();
|
|
/// }
|
|
///
|
|
/// the local type escapes and could be referenced in some TUs but not in
|
|
/// others. Pretend that all local typedefs are always referenced, to not warn
|
|
/// on this. This isn't necessary if f has internal linkage, or the typedef
|
|
/// is private.
|
|
class LocalTypedefNameReferencer
|
|
: public RecursiveASTVisitor<LocalTypedefNameReferencer> {
|
|
public:
|
|
LocalTypedefNameReferencer(Sema &S) : S(S) {}
|
|
bool VisitRecordType(const RecordType *RT);
|
|
private:
|
|
Sema &S;
|
|
};
|
|
bool LocalTypedefNameReferencer::VisitRecordType(const RecordType *RT) {
|
|
auto *R = dyn_cast<CXXRecordDecl>(RT->getDecl());
|
|
if (!R || !R->isLocalClass() || !R->isLocalClass()->isExternallyVisible() ||
|
|
R->isDependentType())
|
|
return true;
|
|
for (auto *TmpD : R->decls())
|
|
if (auto *T = dyn_cast<TypedefNameDecl>(TmpD))
|
|
if (T->getAccess() != AS_private || R->hasFriends())
|
|
S.MarkAnyDeclReferenced(T->getLocation(), T, /*OdrUse=*/false);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
TypeLoc Sema::getReturnTypeLoc(FunctionDecl *FD) const {
|
|
TypeLoc TL = FD->getTypeSourceInfo()->getTypeLoc().IgnoreParens();
|
|
while (auto ATL = TL.getAs<AttributedTypeLoc>())
|
|
TL = ATL.getModifiedLoc().IgnoreParens();
|
|
return TL.castAs<FunctionProtoTypeLoc>().getReturnLoc();
|
|
}
|
|
|
|
/// Deduce the return type for a function from a returned expression, per
|
|
/// C++1y [dcl.spec.auto]p6.
|
|
bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
|
|
SourceLocation ReturnLoc,
|
|
Expr *&RetExpr,
|
|
AutoType *AT) {
|
|
TypeLoc OrigResultType = getReturnTypeLoc(FD);
|
|
QualType Deduced;
|
|
|
|
if (RetExpr && isa<InitListExpr>(RetExpr)) {
|
|
// If the deduction is for a return statement and the initializer is
|
|
// a braced-init-list, the program is ill-formed.
|
|
Diag(RetExpr->getExprLoc(),
|
|
getCurLambda() ? diag::err_lambda_return_init_list
|
|
: diag::err_auto_fn_return_init_list)
|
|
<< RetExpr->getSourceRange();
|
|
return true;
|
|
}
|
|
|
|
if (FD->isDependentContext()) {
|
|
// C++1y [dcl.spec.auto]p12:
|
|
// Return type deduction [...] occurs when the definition is
|
|
// instantiated even if the function body contains a return
|
|
// statement with a non-type-dependent operand.
|
|
assert(AT->isDeduced() && "should have deduced to dependent type");
|
|
return false;
|
|
}
|
|
|
|
if (RetExpr) {
|
|
// Otherwise, [...] deduce a value for U using the rules of template
|
|
// argument deduction.
|
|
DeduceAutoResult DAR = DeduceAutoType(OrigResultType, RetExpr, Deduced);
|
|
|
|
if (DAR == DAR_Failed && !FD->isInvalidDecl())
|
|
Diag(RetExpr->getExprLoc(), diag::err_auto_fn_deduction_failure)
|
|
<< OrigResultType.getType() << RetExpr->getType();
|
|
|
|
if (DAR != DAR_Succeeded)
|
|
return true;
|
|
|
|
// If a local type is part of the returned type, mark its fields as
|
|
// referenced.
|
|
LocalTypedefNameReferencer Referencer(*this);
|
|
Referencer.TraverseType(RetExpr->getType());
|
|
} else {
|
|
// In the case of a return with no operand, the initializer is considered
|
|
// to be void().
|
|
//
|
|
// Deduction here can only succeed if the return type is exactly 'cv auto'
|
|
// or 'decltype(auto)', so just check for that case directly.
|
|
if (!OrigResultType.getType()->getAs<AutoType>()) {
|
|
Diag(ReturnLoc, diag::err_auto_fn_return_void_but_not_auto)
|
|
<< OrigResultType.getType();
|
|
return true;
|
|
}
|
|
// We always deduce U = void in this case.
|
|
Deduced = SubstAutoType(OrigResultType.getType(), Context.VoidTy);
|
|
if (Deduced.isNull())
|
|
return true;
|
|
}
|
|
|
|
// If a function with a declared return type that contains a placeholder type
|
|
// has multiple return statements, the return type is deduced for each return
|
|
// statement. [...] if the type deduced is not the same in each deduction,
|
|
// the program is ill-formed.
|
|
QualType DeducedT = AT->getDeducedType();
|
|
if (!DeducedT.isNull() && !FD->isInvalidDecl()) {
|
|
AutoType *NewAT = Deduced->getContainedAutoType();
|
|
// It is possible that NewAT->getDeducedType() is null. When that happens,
|
|
// we should not crash, instead we ignore this deduction.
|
|
if (NewAT->getDeducedType().isNull())
|
|
return false;
|
|
|
|
CanQualType OldDeducedType = Context.getCanonicalFunctionResultType(
|
|
DeducedT);
|
|
CanQualType NewDeducedType = Context.getCanonicalFunctionResultType(
|
|
NewAT->getDeducedType());
|
|
if (!FD->isDependentContext() && OldDeducedType != NewDeducedType) {
|
|
const LambdaScopeInfo *LambdaSI = getCurLambda();
|
|
if (LambdaSI && LambdaSI->HasImplicitReturnType) {
|
|
Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
|
|
<< NewAT->getDeducedType() << DeducedT
|
|
<< true /*IsLambda*/;
|
|
} else {
|
|
Diag(ReturnLoc, diag::err_auto_fn_different_deductions)
|
|
<< (AT->isDecltypeAuto() ? 1 : 0)
|
|
<< NewAT->getDeducedType() << DeducedT;
|
|
}
|
|
return true;
|
|
}
|
|
} else if (!FD->isInvalidDecl()) {
|
|
// Update all declarations of the function to have the deduced return type.
|
|
Context.adjustDeducedFunctionResultType(FD, Deduced);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
|
|
Scope *CurScope) {
|
|
StmtResult R = BuildReturnStmt(ReturnLoc, RetValExp);
|
|
if (R.isInvalid() || ExprEvalContexts.back().Context ==
|
|
ExpressionEvaluationContext::DiscardedStatement)
|
|
return R;
|
|
|
|
if (VarDecl *VD =
|
|
const_cast<VarDecl*>(cast<ReturnStmt>(R.get())->getNRVOCandidate())) {
|
|
CurScope->addNRVOCandidate(VD);
|
|
} else {
|
|
CurScope->setNoNRVO();
|
|
}
|
|
|
|
CheckJumpOutOfSEHFinally(*this, ReturnLoc, *CurScope->getFnParent());
|
|
|
|
return R;
|
|
}
|
|
|
|
StmtResult Sema::BuildReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
|
|
// Check for unexpanded parameter packs.
|
|
if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
|
|
return StmtError();
|
|
|
|
if (isa<CapturingScopeInfo>(getCurFunction()))
|
|
return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
|
|
|
|
QualType FnRetType;
|
|
QualType RelatedRetType;
|
|
const AttrVec *Attrs = nullptr;
|
|
bool isObjCMethod = false;
|
|
|
|
if (const FunctionDecl *FD = getCurFunctionDecl()) {
|
|
FnRetType = FD->getReturnType();
|
|
if (FD->hasAttrs())
|
|
Attrs = &FD->getAttrs();
|
|
if (FD->isNoReturn())
|
|
Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
|
|
<< FD->getDeclName();
|
|
if (FD->isMain() && RetValExp)
|
|
if (isa<CXXBoolLiteralExpr>(RetValExp))
|
|
Diag(ReturnLoc, diag::warn_main_returns_bool_literal)
|
|
<< RetValExp->getSourceRange();
|
|
} else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
|
|
FnRetType = MD->getReturnType();
|
|
isObjCMethod = true;
|
|
if (MD->hasAttrs())
|
|
Attrs = &MD->getAttrs();
|
|
if (MD->hasRelatedResultType() && MD->getClassInterface()) {
|
|
// In the implementation of a method with a related return type, the
|
|
// type used to type-check the validity of return statements within the
|
|
// method body is a pointer to the type of the class being implemented.
|
|
RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface());
|
|
RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType);
|
|
}
|
|
} else // If we don't have a function/method context, bail.
|
|
return StmtError();
|
|
|
|
// C++1z: discarded return statements are not considered when deducing a
|
|
// return type.
|
|
if (ExprEvalContexts.back().Context ==
|
|
ExpressionEvaluationContext::DiscardedStatement &&
|
|
FnRetType->getContainedAutoType()) {
|
|
if (RetValExp) {
|
|
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
|
|
if (ER.isInvalid())
|
|
return StmtError();
|
|
RetValExp = ER.get();
|
|
}
|
|
return new (Context) ReturnStmt(ReturnLoc, RetValExp, nullptr);
|
|
}
|
|
|
|
// FIXME: Add a flag to the ScopeInfo to indicate whether we're performing
|
|
// deduction.
|
|
if (getLangOpts().CPlusPlus14) {
|
|
if (AutoType *AT = FnRetType->getContainedAutoType()) {
|
|
FunctionDecl *FD = cast<FunctionDecl>(CurContext);
|
|
if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
|
|
FD->setInvalidDecl();
|
|
return StmtError();
|
|
} else {
|
|
FnRetType = FD->getReturnType();
|
|
}
|
|
}
|
|
}
|
|
|
|
bool HasDependentReturnType = FnRetType->isDependentType();
|
|
|
|
ReturnStmt *Result = nullptr;
|
|
if (FnRetType->isVoidType()) {
|
|
if (RetValExp) {
|
|
if (isa<InitListExpr>(RetValExp)) {
|
|
// We simply never allow init lists as the return value of void
|
|
// functions. This is compatible because this was never allowed before,
|
|
// so there's no legacy code to deal with.
|
|
NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
|
|
int FunctionKind = 0;
|
|
if (isa<ObjCMethodDecl>(CurDecl))
|
|
FunctionKind = 1;
|
|
else if (isa<CXXConstructorDecl>(CurDecl))
|
|
FunctionKind = 2;
|
|
else if (isa<CXXDestructorDecl>(CurDecl))
|
|
FunctionKind = 3;
|
|
|
|
Diag(ReturnLoc, diag::err_return_init_list)
|
|
<< CurDecl->getDeclName() << FunctionKind
|
|
<< RetValExp->getSourceRange();
|
|
|
|
// Drop the expression.
|
|
RetValExp = nullptr;
|
|
} else if (!RetValExp->isTypeDependent()) {
|
|
// C99 6.8.6.4p1 (ext_ since GCC warns)
|
|
unsigned D = diag::ext_return_has_expr;
|
|
if (RetValExp->getType()->isVoidType()) {
|
|
NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
|
|
if (isa<CXXConstructorDecl>(CurDecl) ||
|
|
isa<CXXDestructorDecl>(CurDecl))
|
|
D = diag::err_ctor_dtor_returns_void;
|
|
else
|
|
D = diag::ext_return_has_void_expr;
|
|
}
|
|
else {
|
|
ExprResult Result = RetValExp;
|
|
Result = IgnoredValueConversions(Result.get());
|
|
if (Result.isInvalid())
|
|
return StmtError();
|
|
RetValExp = Result.get();
|
|
RetValExp = ImpCastExprToType(RetValExp,
|
|
Context.VoidTy, CK_ToVoid).get();
|
|
}
|
|
// return of void in constructor/destructor is illegal in C++.
|
|
if (D == diag::err_ctor_dtor_returns_void) {
|
|
NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
|
|
Diag(ReturnLoc, D)
|
|
<< CurDecl->getDeclName() << isa<CXXDestructorDecl>(CurDecl)
|
|
<< RetValExp->getSourceRange();
|
|
}
|
|
// return (some void expression); is legal in C++.
|
|
else if (D != diag::ext_return_has_void_expr ||
|
|
!getLangOpts().CPlusPlus) {
|
|
NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
|
|
|
|
int FunctionKind = 0;
|
|
if (isa<ObjCMethodDecl>(CurDecl))
|
|
FunctionKind = 1;
|
|
else if (isa<CXXConstructorDecl>(CurDecl))
|
|
FunctionKind = 2;
|
|
else if (isa<CXXDestructorDecl>(CurDecl))
|
|
FunctionKind = 3;
|
|
|
|
Diag(ReturnLoc, D)
|
|
<< CurDecl->getDeclName() << FunctionKind
|
|
<< RetValExp->getSourceRange();
|
|
}
|
|
}
|
|
|
|
if (RetValExp) {
|
|
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
|
|
if (ER.isInvalid())
|
|
return StmtError();
|
|
RetValExp = ER.get();
|
|
}
|
|
}
|
|
|
|
Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, nullptr);
|
|
} else if (!RetValExp && !HasDependentReturnType) {
|
|
FunctionDecl *FD = getCurFunctionDecl();
|
|
|
|
unsigned DiagID;
|
|
if (getLangOpts().CPlusPlus11 && FD && FD->isConstexpr()) {
|
|
// C++11 [stmt.return]p2
|
|
DiagID = diag::err_constexpr_return_missing_expr;
|
|
FD->setInvalidDecl();
|
|
} else if (getLangOpts().C99) {
|
|
// C99 6.8.6.4p1 (ext_ since GCC warns)
|
|
DiagID = diag::ext_return_missing_expr;
|
|
} else {
|
|
// C90 6.6.6.4p4
|
|
DiagID = diag::warn_return_missing_expr;
|
|
}
|
|
|
|
if (FD)
|
|
Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/;
|
|
else
|
|
Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/;
|
|
|
|
Result = new (Context) ReturnStmt(ReturnLoc);
|
|
} else {
|
|
assert(RetValExp || HasDependentReturnType);
|
|
const VarDecl *NRVOCandidate = nullptr;
|
|
|
|
QualType RetType = RelatedRetType.isNull() ? FnRetType : RelatedRetType;
|
|
|
|
// C99 6.8.6.4p3(136): The return statement is not an assignment. The
|
|
// overlap restriction of subclause 6.5.16.1 does not apply to the case of
|
|
// function return.
|
|
|
|
// In C++ the return statement is handled via a copy initialization,
|
|
// the C version of which boils down to CheckSingleAssignmentConstraints.
|
|
if (RetValExp)
|
|
NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
|
|
if (!HasDependentReturnType && !RetValExp->isTypeDependent()) {
|
|
// we have a non-void function with an expression, continue checking
|
|
InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
|
|
RetType,
|
|
NRVOCandidate != nullptr);
|
|
ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
|
|
RetType, RetValExp);
|
|
if (Res.isInvalid()) {
|
|
// FIXME: Clean up temporaries here anyway?
|
|
return StmtError();
|
|
}
|
|
RetValExp = Res.getAs<Expr>();
|
|
|
|
// If we have a related result type, we need to implicitly
|
|
// convert back to the formal result type. We can't pretend to
|
|
// initialize the result again --- we might end double-retaining
|
|
// --- so instead we initialize a notional temporary.
|
|
if (!RelatedRetType.isNull()) {
|
|
Entity = InitializedEntity::InitializeRelatedResult(getCurMethodDecl(),
|
|
FnRetType);
|
|
Res = PerformCopyInitialization(Entity, ReturnLoc, RetValExp);
|
|
if (Res.isInvalid()) {
|
|
// FIXME: Clean up temporaries here anyway?
|
|
return StmtError();
|
|
}
|
|
RetValExp = Res.getAs<Expr>();
|
|
}
|
|
|
|
CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc, isObjCMethod, Attrs,
|
|
getCurFunctionDecl());
|
|
}
|
|
|
|
if (RetValExp) {
|
|
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
|
|
if (ER.isInvalid())
|
|
return StmtError();
|
|
RetValExp = ER.get();
|
|
}
|
|
Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate);
|
|
}
|
|
|
|
// If we need to check for the named return value optimization, save the
|
|
// return statement in our scope for later processing.
|
|
if (Result->getNRVOCandidate())
|
|
FunctionScopes.back()->Returns.push_back(Result);
|
|
|
|
if (FunctionScopes.back()->FirstReturnLoc.isInvalid())
|
|
FunctionScopes.back()->FirstReturnLoc = ReturnLoc;
|
|
|
|
return Result;
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
|
|
SourceLocation RParen, Decl *Parm,
|
|
Stmt *Body) {
|
|
VarDecl *Var = cast_or_null<VarDecl>(Parm);
|
|
if (Var && Var->isInvalidDecl())
|
|
return StmtError();
|
|
|
|
return new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
|
|
return new (Context) ObjCAtFinallyStmt(AtLoc, Body);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
|
|
MultiStmtArg CatchStmts, Stmt *Finally) {
|
|
if (!getLangOpts().ObjCExceptions)
|
|
Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try";
|
|
|
|
getCurFunction()->setHasBranchProtectedScope();
|
|
unsigned NumCatchStmts = CatchStmts.size();
|
|
return ObjCAtTryStmt::Create(Context, AtLoc, Try, CatchStmts.data(),
|
|
NumCatchStmts, Finally);
|
|
}
|
|
|
|
StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw) {
|
|
if (Throw) {
|
|
ExprResult Result = DefaultLvalueConversion(Throw);
|
|
if (Result.isInvalid())
|
|
return StmtError();
|
|
|
|
Result = ActOnFinishFullExpr(Result.get());
|
|
if (Result.isInvalid())
|
|
return StmtError();
|
|
Throw = Result.get();
|
|
|
|
QualType ThrowType = Throw->getType();
|
|
// Make sure the expression type is an ObjC pointer or "void *".
|
|
if (!ThrowType->isDependentType() &&
|
|
!ThrowType->isObjCObjectPointerType()) {
|
|
const PointerType *PT = ThrowType->getAs<PointerType>();
|
|
if (!PT || !PT->getPointeeType()->isVoidType())
|
|
return StmtError(Diag(AtLoc, diag::err_objc_throw_expects_object)
|
|
<< Throw->getType() << Throw->getSourceRange());
|
|
}
|
|
}
|
|
|
|
return new (Context) ObjCAtThrowStmt(AtLoc, Throw);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
|
|
Scope *CurScope) {
|
|
if (!getLangOpts().ObjCExceptions)
|
|
Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw";
|
|
|
|
if (!Throw) {
|
|
// @throw without an expression designates a rethrow (which must occur
|
|
// in the context of an @catch clause).
|
|
Scope *AtCatchParent = CurScope;
|
|
while (AtCatchParent && !AtCatchParent->isAtCatchScope())
|
|
AtCatchParent = AtCatchParent->getParent();
|
|
if (!AtCatchParent)
|
|
return StmtError(Diag(AtLoc, diag::err_rethrow_used_outside_catch));
|
|
}
|
|
return BuildObjCAtThrowStmt(AtLoc, Throw);
|
|
}
|
|
|
|
ExprResult
|
|
Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) {
|
|
ExprResult result = DefaultLvalueConversion(operand);
|
|
if (result.isInvalid())
|
|
return ExprError();
|
|
operand = result.get();
|
|
|
|
// Make sure the expression type is an ObjC pointer or "void *".
|
|
QualType type = operand->getType();
|
|
if (!type->isDependentType() &&
|
|
!type->isObjCObjectPointerType()) {
|
|
const PointerType *pointerType = type->getAs<PointerType>();
|
|
if (!pointerType || !pointerType->getPointeeType()->isVoidType()) {
|
|
if (getLangOpts().CPlusPlus) {
|
|
if (RequireCompleteType(atLoc, type,
|
|
diag::err_incomplete_receiver_type))
|
|
return Diag(atLoc, diag::err_objc_synchronized_expects_object)
|
|
<< type << operand->getSourceRange();
|
|
|
|
ExprResult result = PerformContextuallyConvertToObjCPointer(operand);
|
|
if (result.isInvalid())
|
|
return ExprError();
|
|
if (!result.isUsable())
|
|
return Diag(atLoc, diag::err_objc_synchronized_expects_object)
|
|
<< type << operand->getSourceRange();
|
|
|
|
operand = result.get();
|
|
} else {
|
|
return Diag(atLoc, diag::err_objc_synchronized_expects_object)
|
|
<< type << operand->getSourceRange();
|
|
}
|
|
}
|
|
}
|
|
|
|
// The operand to @synchronized is a full-expression.
|
|
return ActOnFinishFullExpr(operand);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr,
|
|
Stmt *SyncBody) {
|
|
// We can't jump into or indirect-jump out of a @synchronized block.
|
|
getCurFunction()->setHasBranchProtectedScope();
|
|
return new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody);
|
|
}
|
|
|
|
/// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
|
|
/// and creates a proper catch handler from them.
|
|
StmtResult
|
|
Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl,
|
|
Stmt *HandlerBlock) {
|
|
// There's nothing to test that ActOnExceptionDecl didn't already test.
|
|
return new (Context)
|
|
CXXCatchStmt(CatchLoc, cast_or_null<VarDecl>(ExDecl), HandlerBlock);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) {
|
|
getCurFunction()->setHasBranchProtectedScope();
|
|
return new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body);
|
|
}
|
|
|
|
namespace {
|
|
class CatchHandlerType {
|
|
QualType QT;
|
|
unsigned IsPointer : 1;
|
|
|
|
// This is a special constructor to be used only with DenseMapInfo's
|
|
// getEmptyKey() and getTombstoneKey() functions.
|
|
friend struct llvm::DenseMapInfo<CatchHandlerType>;
|
|
enum Unique { ForDenseMap };
|
|
CatchHandlerType(QualType QT, Unique) : QT(QT), IsPointer(false) {}
|
|
|
|
public:
|
|
/// Used when creating a CatchHandlerType from a handler type; will determine
|
|
/// whether the type is a pointer or reference and will strip off the top
|
|
/// level pointer and cv-qualifiers.
|
|
CatchHandlerType(QualType Q) : QT(Q), IsPointer(false) {
|
|
if (QT->isPointerType())
|
|
IsPointer = true;
|
|
|
|
if (IsPointer || QT->isReferenceType())
|
|
QT = QT->getPointeeType();
|
|
QT = QT.getUnqualifiedType();
|
|
}
|
|
|
|
/// Used when creating a CatchHandlerType from a base class type; pretends the
|
|
/// type passed in had the pointer qualifier, does not need to get an
|
|
/// unqualified type.
|
|
CatchHandlerType(QualType QT, bool IsPointer)
|
|
: QT(QT), IsPointer(IsPointer) {}
|
|
|
|
QualType underlying() const { return QT; }
|
|
bool isPointer() const { return IsPointer; }
|
|
|
|
friend bool operator==(const CatchHandlerType &LHS,
|
|
const CatchHandlerType &RHS) {
|
|
// If the pointer qualification does not match, we can return early.
|
|
if (LHS.IsPointer != RHS.IsPointer)
|
|
return false;
|
|
// Otherwise, check the underlying type without cv-qualifiers.
|
|
return LHS.QT == RHS.QT;
|
|
}
|
|
};
|
|
} // namespace
|
|
|
|
namespace llvm {
|
|
template <> struct DenseMapInfo<CatchHandlerType> {
|
|
static CatchHandlerType getEmptyKey() {
|
|
return CatchHandlerType(DenseMapInfo<QualType>::getEmptyKey(),
|
|
CatchHandlerType::ForDenseMap);
|
|
}
|
|
|
|
static CatchHandlerType getTombstoneKey() {
|
|
return CatchHandlerType(DenseMapInfo<QualType>::getTombstoneKey(),
|
|
CatchHandlerType::ForDenseMap);
|
|
}
|
|
|
|
static unsigned getHashValue(const CatchHandlerType &Base) {
|
|
return DenseMapInfo<QualType>::getHashValue(Base.underlying());
|
|
}
|
|
|
|
static bool isEqual(const CatchHandlerType &LHS,
|
|
const CatchHandlerType &RHS) {
|
|
return LHS == RHS;
|
|
}
|
|
};
|
|
}
|
|
|
|
namespace {
|
|
class CatchTypePublicBases {
|
|
ASTContext &Ctx;
|
|
const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &TypesToCheck;
|
|
const bool CheckAgainstPointer;
|
|
|
|
CXXCatchStmt *FoundHandler;
|
|
CanQualType FoundHandlerType;
|
|
|
|
public:
|
|
CatchTypePublicBases(
|
|
ASTContext &Ctx,
|
|
const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &T, bool C)
|
|
: Ctx(Ctx), TypesToCheck(T), CheckAgainstPointer(C),
|
|
FoundHandler(nullptr) {}
|
|
|
|
CXXCatchStmt *getFoundHandler() const { return FoundHandler; }
|
|
CanQualType getFoundHandlerType() const { return FoundHandlerType; }
|
|
|
|
bool operator()(const CXXBaseSpecifier *S, CXXBasePath &) {
|
|
if (S->getAccessSpecifier() == AccessSpecifier::AS_public) {
|
|
CatchHandlerType Check(S->getType(), CheckAgainstPointer);
|
|
const auto &M = TypesToCheck;
|
|
auto I = M.find(Check);
|
|
if (I != M.end()) {
|
|
FoundHandler = I->second;
|
|
FoundHandlerType = Ctx.getCanonicalType(S->getType());
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
};
|
|
}
|
|
|
|
/// ActOnCXXTryBlock - Takes a try compound-statement and a number of
|
|
/// handlers and creates a try statement from them.
|
|
StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
|
|
ArrayRef<Stmt *> Handlers) {
|
|
// Don't report an error if 'try' is used in system headers.
|
|
if (!getLangOpts().CXXExceptions &&
|
|
!getSourceManager().isInSystemHeader(TryLoc))
|
|
Diag(TryLoc, diag::err_exceptions_disabled) << "try";
|
|
|
|
// Exceptions aren't allowed in CUDA device code.
|
|
if (getLangOpts().CUDA)
|
|
CUDADiagIfDeviceCode(TryLoc, diag::err_cuda_device_exceptions)
|
|
<< "try" << CurrentCUDATarget();
|
|
|
|
if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
|
|
Diag(TryLoc, diag::err_omp_simd_region_cannot_use_stmt) << "try";
|
|
|
|
sema::FunctionScopeInfo *FSI = getCurFunction();
|
|
|
|
// C++ try is incompatible with SEH __try.
|
|
if (!getLangOpts().Borland && FSI->FirstSEHTryLoc.isValid()) {
|
|
Diag(TryLoc, diag::err_mixing_cxx_try_seh_try);
|
|
Diag(FSI->FirstSEHTryLoc, diag::note_conflicting_try_here) << "'__try'";
|
|
}
|
|
|
|
const unsigned NumHandlers = Handlers.size();
|
|
assert(!Handlers.empty() &&
|
|
"The parser shouldn't call this if there are no handlers.");
|
|
|
|
llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> HandledTypes;
|
|
for (unsigned i = 0; i < NumHandlers; ++i) {
|
|
CXXCatchStmt *H = cast<CXXCatchStmt>(Handlers[i]);
|
|
|
|
// Diagnose when the handler is a catch-all handler, but it isn't the last
|
|
// handler for the try block. [except.handle]p5. Also, skip exception
|
|
// declarations that are invalid, since we can't usefully report on them.
|
|
if (!H->getExceptionDecl()) {
|
|
if (i < NumHandlers - 1)
|
|
return StmtError(Diag(H->getLocStart(), diag::err_early_catch_all));
|
|
continue;
|
|
} else if (H->getExceptionDecl()->isInvalidDecl())
|
|
continue;
|
|
|
|
// Walk the type hierarchy to diagnose when this type has already been
|
|
// handled (duplication), or cannot be handled (derivation inversion). We
|
|
// ignore top-level cv-qualifiers, per [except.handle]p3
|
|
CatchHandlerType HandlerCHT =
|
|
(QualType)Context.getCanonicalType(H->getCaughtType());
|
|
|
|
// We can ignore whether the type is a reference or a pointer; we need the
|
|
// underlying declaration type in order to get at the underlying record
|
|
// decl, if there is one.
|
|
QualType Underlying = HandlerCHT.underlying();
|
|
if (auto *RD = Underlying->getAsCXXRecordDecl()) {
|
|
if (!RD->hasDefinition())
|
|
continue;
|
|
// Check that none of the public, unambiguous base classes are in the
|
|
// map ([except.handle]p1). Give the base classes the same pointer
|
|
// qualification as the original type we are basing off of. This allows
|
|
// comparison against the handler type using the same top-level pointer
|
|
// as the original type.
|
|
CXXBasePaths Paths;
|
|
Paths.setOrigin(RD);
|
|
CatchTypePublicBases CTPB(Context, HandledTypes, HandlerCHT.isPointer());
|
|
if (RD->lookupInBases(CTPB, Paths)) {
|
|
const CXXCatchStmt *Problem = CTPB.getFoundHandler();
|
|
if (!Paths.isAmbiguous(CTPB.getFoundHandlerType())) {
|
|
Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
|
|
diag::warn_exception_caught_by_earlier_handler)
|
|
<< H->getCaughtType();
|
|
Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
|
|
diag::note_previous_exception_handler)
|
|
<< Problem->getCaughtType();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add the type the list of ones we have handled; diagnose if we've already
|
|
// handled it.
|
|
auto R = HandledTypes.insert(std::make_pair(H->getCaughtType(), H));
|
|
if (!R.second) {
|
|
const CXXCatchStmt *Problem = R.first->second;
|
|
Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
|
|
diag::warn_exception_caught_by_earlier_handler)
|
|
<< H->getCaughtType();
|
|
Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
|
|
diag::note_previous_exception_handler)
|
|
<< Problem->getCaughtType();
|
|
}
|
|
}
|
|
|
|
FSI->setHasCXXTry(TryLoc);
|
|
|
|
return CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers);
|
|
}
|
|
|
|
StmtResult Sema::ActOnSEHTryBlock(bool IsCXXTry, SourceLocation TryLoc,
|
|
Stmt *TryBlock, Stmt *Handler) {
|
|
assert(TryBlock && Handler);
|
|
|
|
sema::FunctionScopeInfo *FSI = getCurFunction();
|
|
|
|
// SEH __try is incompatible with C++ try. Borland appears to support this,
|
|
// however.
|
|
if (!getLangOpts().Borland) {
|
|
if (FSI->FirstCXXTryLoc.isValid()) {
|
|
Diag(TryLoc, diag::err_mixing_cxx_try_seh_try);
|
|
Diag(FSI->FirstCXXTryLoc, diag::note_conflicting_try_here) << "'try'";
|
|
}
|
|
}
|
|
|
|
FSI->setHasSEHTry(TryLoc);
|
|
|
|
// Reject __try in Obj-C methods, blocks, and captured decls, since we don't
|
|
// track if they use SEH.
|
|
DeclContext *DC = CurContext;
|
|
while (DC && !DC->isFunctionOrMethod())
|
|
DC = DC->getParent();
|
|
FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(DC);
|
|
if (FD)
|
|
FD->setUsesSEHTry(true);
|
|
else
|
|
Diag(TryLoc, diag::err_seh_try_outside_functions);
|
|
|
|
// Reject __try on unsupported targets.
|
|
if (!Context.getTargetInfo().isSEHTrySupported())
|
|
Diag(TryLoc, diag::err_seh_try_unsupported);
|
|
|
|
return SEHTryStmt::Create(Context, IsCXXTry, TryLoc, TryBlock, Handler);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnSEHExceptBlock(SourceLocation Loc,
|
|
Expr *FilterExpr,
|
|
Stmt *Block) {
|
|
assert(FilterExpr && Block);
|
|
|
|
if(!FilterExpr->getType()->isIntegerType()) {
|
|
return StmtError(Diag(FilterExpr->getExprLoc(),
|
|
diag::err_filter_expression_integral)
|
|
<< FilterExpr->getType());
|
|
}
|
|
|
|
return SEHExceptStmt::Create(Context,Loc,FilterExpr,Block);
|
|
}
|
|
|
|
void Sema::ActOnStartSEHFinallyBlock() {
|
|
CurrentSEHFinally.push_back(CurScope);
|
|
}
|
|
|
|
void Sema::ActOnAbortSEHFinallyBlock() {
|
|
CurrentSEHFinally.pop_back();
|
|
}
|
|
|
|
StmtResult Sema::ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block) {
|
|
assert(Block);
|
|
CurrentSEHFinally.pop_back();
|
|
return SEHFinallyStmt::Create(Context, Loc, Block);
|
|
}
|
|
|
|
StmtResult
|
|
Sema::ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope) {
|
|
Scope *SEHTryParent = CurScope;
|
|
while (SEHTryParent && !SEHTryParent->isSEHTryScope())
|
|
SEHTryParent = SEHTryParent->getParent();
|
|
if (!SEHTryParent)
|
|
return StmtError(Diag(Loc, diag::err_ms___leave_not_in___try));
|
|
CheckJumpOutOfSEHFinally(*this, Loc, *SEHTryParent);
|
|
|
|
return new (Context) SEHLeaveStmt(Loc);
|
|
}
|
|
|
|
StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
|
|
bool IsIfExists,
|
|
NestedNameSpecifierLoc QualifierLoc,
|
|
DeclarationNameInfo NameInfo,
|
|
Stmt *Nested)
|
|
{
|
|
return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists,
|
|
QualifierLoc, NameInfo,
|
|
cast<CompoundStmt>(Nested));
|
|
}
|
|
|
|
|
|
StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
|
|
bool IsIfExists,
|
|
CXXScopeSpec &SS,
|
|
UnqualifiedId &Name,
|
|
Stmt *Nested) {
|
|
return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists,
|
|
SS.getWithLocInContext(Context),
|
|
GetNameFromUnqualifiedId(Name),
|
|
Nested);
|
|
}
|
|
|
|
RecordDecl*
|
|
Sema::CreateCapturedStmtRecordDecl(CapturedDecl *&CD, SourceLocation Loc,
|
|
unsigned NumParams) {
|
|
DeclContext *DC = CurContext;
|
|
while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
|
|
DC = DC->getParent();
|
|
|
|
RecordDecl *RD = nullptr;
|
|
if (getLangOpts().CPlusPlus)
|
|
RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc,
|
|
/*Id=*/nullptr);
|
|
else
|
|
RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/nullptr);
|
|
|
|
RD->setCapturedRecord();
|
|
DC->addDecl(RD);
|
|
RD->setImplicit();
|
|
RD->startDefinition();
|
|
|
|
assert(NumParams > 0 && "CapturedStmt requires context parameter");
|
|
CD = CapturedDecl::Create(Context, CurContext, NumParams);
|
|
DC->addDecl(CD);
|
|
return RD;
|
|
}
|
|
|
|
static void buildCapturedStmtCaptureList(
|
|
SmallVectorImpl<CapturedStmt::Capture> &Captures,
|
|
SmallVectorImpl<Expr *> &CaptureInits,
|
|
ArrayRef<CapturingScopeInfo::Capture> Candidates) {
|
|
|
|
typedef ArrayRef<CapturingScopeInfo::Capture>::const_iterator CaptureIter;
|
|
for (CaptureIter Cap = Candidates.begin(); Cap != Candidates.end(); ++Cap) {
|
|
|
|
if (Cap->isThisCapture()) {
|
|
Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
|
|
CapturedStmt::VCK_This));
|
|
CaptureInits.push_back(Cap->getInitExpr());
|
|
continue;
|
|
} else if (Cap->isVLATypeCapture()) {
|
|
Captures.push_back(
|
|
CapturedStmt::Capture(Cap->getLocation(), CapturedStmt::VCK_VLAType));
|
|
CaptureInits.push_back(nullptr);
|
|
continue;
|
|
}
|
|
|
|
Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
|
|
Cap->isReferenceCapture()
|
|
? CapturedStmt::VCK_ByRef
|
|
: CapturedStmt::VCK_ByCopy,
|
|
Cap->getVariable()));
|
|
CaptureInits.push_back(Cap->getInitExpr());
|
|
}
|
|
}
|
|
|
|
void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
|
|
CapturedRegionKind Kind,
|
|
unsigned NumParams) {
|
|
CapturedDecl *CD = nullptr;
|
|
RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams);
|
|
|
|
// Build the context parameter
|
|
DeclContext *DC = CapturedDecl::castToDeclContext(CD);
|
|
IdentifierInfo *ParamName = &Context.Idents.get("__context");
|
|
QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
|
|
ImplicitParamDecl *Param
|
|
= ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
|
|
DC->addDecl(Param);
|
|
|
|
CD->setContextParam(0, Param);
|
|
|
|
// Enter the capturing scope for this captured region.
|
|
PushCapturedRegionScope(CurScope, CD, RD, Kind);
|
|
|
|
if (CurScope)
|
|
PushDeclContext(CurScope, CD);
|
|
else
|
|
CurContext = CD;
|
|
|
|
PushExpressionEvaluationContext(
|
|
ExpressionEvaluationContext::PotentiallyEvaluated);
|
|
}
|
|
|
|
void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
|
|
CapturedRegionKind Kind,
|
|
ArrayRef<CapturedParamNameType> Params) {
|
|
CapturedDecl *CD = nullptr;
|
|
RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, Params.size());
|
|
|
|
// Build the context parameter
|
|
DeclContext *DC = CapturedDecl::castToDeclContext(CD);
|
|
bool ContextIsFound = false;
|
|
unsigned ParamNum = 0;
|
|
for (ArrayRef<CapturedParamNameType>::iterator I = Params.begin(),
|
|
E = Params.end();
|
|
I != E; ++I, ++ParamNum) {
|
|
if (I->second.isNull()) {
|
|
assert(!ContextIsFound &&
|
|
"null type has been found already for '__context' parameter");
|
|
IdentifierInfo *ParamName = &Context.Idents.get("__context");
|
|
QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
|
|
ImplicitParamDecl *Param
|
|
= ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
|
|
DC->addDecl(Param);
|
|
CD->setContextParam(ParamNum, Param);
|
|
ContextIsFound = true;
|
|
} else {
|
|
IdentifierInfo *ParamName = &Context.Idents.get(I->first);
|
|
ImplicitParamDecl *Param
|
|
= ImplicitParamDecl::Create(Context, DC, Loc, ParamName, I->second);
|
|
DC->addDecl(Param);
|
|
CD->setParam(ParamNum, Param);
|
|
}
|
|
}
|
|
assert(ContextIsFound && "no null type for '__context' parameter");
|
|
if (!ContextIsFound) {
|
|
// Add __context implicitly if it is not specified.
|
|
IdentifierInfo *ParamName = &Context.Idents.get("__context");
|
|
QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
|
|
ImplicitParamDecl *Param =
|
|
ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
|
|
DC->addDecl(Param);
|
|
CD->setContextParam(ParamNum, Param);
|
|
}
|
|
// Enter the capturing scope for this captured region.
|
|
PushCapturedRegionScope(CurScope, CD, RD, Kind);
|
|
|
|
if (CurScope)
|
|
PushDeclContext(CurScope, CD);
|
|
else
|
|
CurContext = CD;
|
|
|
|
PushExpressionEvaluationContext(
|
|
ExpressionEvaluationContext::PotentiallyEvaluated);
|
|
}
|
|
|
|
void Sema::ActOnCapturedRegionError() {
|
|
DiscardCleanupsInEvaluationContext();
|
|
PopExpressionEvaluationContext();
|
|
|
|
CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
|
|
RecordDecl *Record = RSI->TheRecordDecl;
|
|
Record->setInvalidDecl();
|
|
|
|
SmallVector<Decl*, 4> Fields(Record->fields());
|
|
ActOnFields(/*Scope=*/nullptr, Record->getLocation(), Record, Fields,
|
|
SourceLocation(), SourceLocation(), /*AttributeList=*/nullptr);
|
|
|
|
PopDeclContext();
|
|
PopFunctionScopeInfo();
|
|
}
|
|
|
|
StmtResult Sema::ActOnCapturedRegionEnd(Stmt *S) {
|
|
CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
|
|
|
|
SmallVector<CapturedStmt::Capture, 4> Captures;
|
|
SmallVector<Expr *, 4> CaptureInits;
|
|
buildCapturedStmtCaptureList(Captures, CaptureInits, RSI->Captures);
|
|
|
|
CapturedDecl *CD = RSI->TheCapturedDecl;
|
|
RecordDecl *RD = RSI->TheRecordDecl;
|
|
|
|
CapturedStmt *Res = CapturedStmt::Create(
|
|
getASTContext(), S, static_cast<CapturedRegionKind>(RSI->CapRegionKind),
|
|
Captures, CaptureInits, CD, RD);
|
|
|
|
CD->setBody(Res->getCapturedStmt());
|
|
RD->completeDefinition();
|
|
|
|
DiscardCleanupsInEvaluationContext();
|
|
PopExpressionEvaluationContext();
|
|
|
|
PopDeclContext();
|
|
PopFunctionScopeInfo();
|
|
|
|
return Res;
|
|
}
|