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freebsd-dev/contrib/llvm/tools/clang/lib/Sema/SemaStmt.cpp
Dimitry Andric f785676f2a Upgrade our copy of llvm/clang to 3.4 release. This version supports 
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.

The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3.  The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.

Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>

MFC after:	1 month
2014-02-16 19:44:07 +00:00

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//===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for statements.
//
//===----------------------------------------------------------------------===//
#include "clang/Sema/SemaInternal.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTDiagnostic.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/StmtCXX.h"
#include "clang/AST/StmtObjC.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
using namespace clang;
using namespace sema;
StmtResult Sema::ActOnExprStmt(ExprResult FE) {
if (FE.isInvalid())
return StmtError();
FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(),
/*DiscardedValue*/ true);
if (FE.isInvalid())
return StmtError();
// C99 6.8.3p2: The expression in an expression statement is evaluated as a
// void expression for its side effects. Conversion to void allows any
// operand, even incomplete types.
// Same thing in for stmt first clause (when expr) and third clause.
return Owned(static_cast<Stmt*>(FE.take()));
}
StmtResult Sema::ActOnExprStmtError() {
DiscardCleanupsInEvaluationContext();
return StmtError();
}
StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
bool HasLeadingEmptyMacro) {
return Owned(new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro));
}
StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
SourceLocation EndLoc) {
DeclGroupRef DG = dg.get();
// If we have an invalid decl, just return an error.
if (DG.isNull()) return StmtError();
return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc));
}
void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
DeclGroupRef DG = dg.get();
// If we don't have a declaration, or we have an invalid declaration,
// just return.
if (DG.isNull() || !DG.isSingleDecl())
return;
Decl *decl = DG.getSingleDecl();
if (!decl || decl->isInvalidDecl())
return;
// Only variable declarations are permitted.
VarDecl *var = dyn_cast<VarDecl>(decl);
if (!var) {
Diag(decl->getLocation(), diag::err_non_variable_decl_in_for);
decl->setInvalidDecl();
return;
}
// foreach variables are never actually initialized in the way that
// the parser came up with.
var->setInit(0);
// In ARC, we don't need to retain the iteration variable of a fast
// enumeration loop. Rather than actually trying to catch that
// during declaration processing, we remove the consequences here.
if (getLangOpts().ObjCAutoRefCount) {
QualType type = var->getType();
// Only do this if we inferred the lifetime. Inferred lifetime
// will show up as a local qualifier because explicit lifetime
// should have shown up as an AttributedType instead.
if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) {
// Add 'const' and mark the variable as pseudo-strong.
var->setType(type.withConst());
var->setARCPseudoStrong(true);
}
}
}
/// \brief Diagnose unused '==' and '!=' as likely typos for '=' or '|='.
///
/// Adding a cast to void (or other expression wrappers) will prevent the
/// warning from firing.
static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) {
SourceLocation Loc;
bool IsNotEqual, CanAssign;
if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
if (Op->getOpcode() != BO_EQ && Op->getOpcode() != BO_NE)
return false;
Loc = Op->getOperatorLoc();
IsNotEqual = Op->getOpcode() == BO_NE;
CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue();
} else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
if (Op->getOperator() != OO_EqualEqual &&
Op->getOperator() != OO_ExclaimEqual)
return false;
Loc = Op->getOperatorLoc();
IsNotEqual = Op->getOperator() == OO_ExclaimEqual;
CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue();
} else {
// Not a typo-prone comparison.
return false;
}
// Suppress warnings when the operator, suspicious as it may be, comes from
// a macro expansion.
if (S.SourceMgr.isMacroBodyExpansion(Loc))
return false;
S.Diag(Loc, diag::warn_unused_comparison)
<< (unsigned)IsNotEqual << E->getSourceRange();
// If the LHS is a plausible entity to assign to, provide a fixit hint to
// correct common typos.
if (CanAssign) {
if (IsNotEqual)
S.Diag(Loc, diag::note_inequality_comparison_to_or_assign)
<< FixItHint::CreateReplacement(Loc, "|=");
else
S.Diag(Loc, diag::note_equality_comparison_to_assign)
<< FixItHint::CreateReplacement(Loc, "=");
}
return true;
}
void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
return DiagnoseUnusedExprResult(Label->getSubStmt());
const Expr *E = dyn_cast_or_null<Expr>(S);
if (!E)
return;
SourceLocation ExprLoc = E->IgnoreParens()->getExprLoc();
// In most cases, we don't want to warn if the expression is written in a
// macro body, or if the macro comes from a system header. If the offending
// expression is a call to a function with the warn_unused_result attribute,
// we warn no matter the location. Because of the order in which the various
// checks need to happen, we factor out the macro-related test here.
bool ShouldSuppress =
SourceMgr.isMacroBodyExpansion(ExprLoc) ||
SourceMgr.isInSystemMacro(ExprLoc);
const Expr *WarnExpr;
SourceLocation Loc;
SourceRange R1, R2;
if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context))
return;
// If this is a GNU statement expression expanded from a macro, it is probably
// unused because it is a function-like macro that can be used as either an
// expression or statement. Don't warn, because it is almost certainly a
// false positive.
if (isa<StmtExpr>(E) && Loc.isMacroID())
return;
// Okay, we have an unused result. Depending on what the base expression is,
// we might want to make a more specific diagnostic. Check for one of these
// cases now.
unsigned DiagID = diag::warn_unused_expr;
if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E))
E = Temps->getSubExpr();
if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
E = TempExpr->getSubExpr();
if (DiagnoseUnusedComparison(*this, E))
return;
E = WarnExpr;
if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
if (E->getType()->isVoidType())
return;
// If the callee has attribute pure, const, or warn_unused_result, warn with
// a more specific message to make it clear what is happening. If the call
// is written in a macro body, only warn if it has the warn_unused_result
// attribute.
if (const Decl *FD = CE->getCalleeDecl()) {
if (FD->getAttr<WarnUnusedResultAttr>()) {
Diag(Loc, diag::warn_unused_result) << R1 << R2;
return;
}
if (ShouldSuppress)
return;
if (FD->getAttr<PureAttr>()) {
Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
return;
}
if (FD->getAttr<ConstAttr>()) {
Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
return;
}
}
} else if (ShouldSuppress)
return;
if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) {
Diag(Loc, diag::err_arc_unused_init_message) << R1;
return;
}
const ObjCMethodDecl *MD = ME->getMethodDecl();
if (MD && MD->getAttr<WarnUnusedResultAttr>()) {
Diag(Loc, diag::warn_unused_result) << R1 << R2;
return;
}
} else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
const Expr *Source = POE->getSyntacticForm();
if (isa<ObjCSubscriptRefExpr>(Source))
DiagID = diag::warn_unused_container_subscript_expr;
else
DiagID = diag::warn_unused_property_expr;
} else if (const CXXFunctionalCastExpr *FC
= dyn_cast<CXXFunctionalCastExpr>(E)) {
if (isa<CXXConstructExpr>(FC->getSubExpr()) ||
isa<CXXTemporaryObjectExpr>(FC->getSubExpr()))
return;
}
// Diagnose "(void*) blah" as a typo for "(void) blah".
else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
QualType T = TI->getType();
// We really do want to use the non-canonical type here.
if (T == Context.VoidPtrTy) {
PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>();
Diag(Loc, diag::warn_unused_voidptr)
<< FixItHint::CreateRemoval(TL.getStarLoc());
return;
}
}
if (E->isGLValue() && E->getType().isVolatileQualified()) {
Diag(Loc, diag::warn_unused_volatile) << R1 << R2;
return;
}
DiagRuntimeBehavior(Loc, 0, PDiag(DiagID) << R1 << R2);
}
void Sema::ActOnStartOfCompoundStmt() {
PushCompoundScope();
}
void Sema::ActOnFinishOfCompoundStmt() {
PopCompoundScope();
}
sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
return getCurFunction()->CompoundScopes.back();
}
StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
ArrayRef<Stmt *> Elts, bool isStmtExpr) {
const unsigned NumElts = Elts.size();
// If we're in C89 mode, check that we don't have any decls after stmts. If
// so, emit an extension diagnostic.
if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) {
// Note that __extension__ can be around a decl.
unsigned i = 0;
// Skip over all declarations.
for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
/*empty*/;
// We found the end of the list or a statement. Scan for another declstmt.
for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
/*empty*/;
if (i != NumElts) {
Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
Diag(D->getLocation(), diag::ext_mixed_decls_code);
}
}
// Warn about unused expressions in statements.
for (unsigned i = 0; i != NumElts; ++i) {
// Ignore statements that are last in a statement expression.
if (isStmtExpr && i == NumElts - 1)
continue;
DiagnoseUnusedExprResult(Elts[i]);
}
// Check for suspicious empty body (null statement) in `for' and `while'
// statements. Don't do anything for template instantiations, this just adds
// noise.
if (NumElts != 0 && !CurrentInstantiationScope &&
getCurCompoundScope().HasEmptyLoopBodies) {
for (unsigned i = 0; i != NumElts - 1; ++i)
DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
}
return Owned(new (Context) CompoundStmt(Context, Elts, L, R));
}
StmtResult
Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
SourceLocation DotDotDotLoc, Expr *RHSVal,
SourceLocation ColonLoc) {
assert((LHSVal != 0) && "missing expression in case statement");
if (getCurFunction()->SwitchStack.empty()) {
Diag(CaseLoc, diag::err_case_not_in_switch);
return StmtError();
}
if (!getLangOpts().CPlusPlus11) {
// C99 6.8.4.2p3: The expression shall be an integer constant.
// However, GCC allows any evaluatable integer expression.
if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) {
LHSVal = VerifyIntegerConstantExpression(LHSVal).take();
if (!LHSVal)
return StmtError();
}
// GCC extension: The expression shall be an integer constant.
if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) {
RHSVal = VerifyIntegerConstantExpression(RHSVal).take();
// Recover from an error by just forgetting about it.
}
}
LHSVal = ActOnFinishFullExpr(LHSVal, LHSVal->getExprLoc(), false,
getLangOpts().CPlusPlus11).take();
if (RHSVal)
RHSVal = ActOnFinishFullExpr(RHSVal, RHSVal->getExprLoc(), false,
getLangOpts().CPlusPlus11).take();
CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc,
ColonLoc);
getCurFunction()->SwitchStack.back()->addSwitchCase(CS);
return Owned(CS);
}
/// ActOnCaseStmtBody - This installs a statement as the body of a case.
void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) {
DiagnoseUnusedExprResult(SubStmt);
CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
CS->setSubStmt(SubStmt);
}
StmtResult
Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
Stmt *SubStmt, Scope *CurScope) {
DiagnoseUnusedExprResult(SubStmt);
if (getCurFunction()->SwitchStack.empty()) {
Diag(DefaultLoc, diag::err_default_not_in_switch);
return Owned(SubStmt);
}
DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
getCurFunction()->SwitchStack.back()->addSwitchCase(DS);
return Owned(DS);
}
StmtResult
Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
SourceLocation ColonLoc, Stmt *SubStmt) {
// If the label was multiply defined, reject it now.
if (TheDecl->getStmt()) {
Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
Diag(TheDecl->getLocation(), diag::note_previous_definition);
return Owned(SubStmt);
}
// 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);
TheDecl->setLocation(IdentLoc);
}
return Owned(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 Owned(LS);
}
StmtResult
Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar,
Stmt *thenStmt, SourceLocation ElseLoc,
Stmt *elseStmt) {
// If the condition was invalid, discard the if statement. We could recover
// better by replacing it with a valid expr, but don't do that yet.
if (!CondVal.get() && !CondVar) {
getCurFunction()->setHasDroppedStmt();
return StmtError();
}
ExprResult CondResult(CondVal.release());
VarDecl *ConditionVar = 0;
if (CondVar) {
ConditionVar = cast<VarDecl>(CondVar);
CondResult = CheckConditionVariable(ConditionVar, IfLoc, true);
if (CondResult.isInvalid())
return StmtError();
}
Expr *ConditionExpr = CondResult.takeAs<Expr>();
if (!ConditionExpr)
return StmtError();
DiagnoseUnusedExprResult(thenStmt);
if (!elseStmt) {
DiagnoseEmptyStmtBody(ConditionExpr->getLocEnd(), thenStmt,
diag::warn_empty_if_body);
}
DiagnoseUnusedExprResult(elseStmt);
return Owned(new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr,
thenStmt, ElseLoc, elseStmt));
}
/// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
/// the specified width and sign. If an overflow occurs, detect it and emit
/// the specified diagnostic.
void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val,
unsigned NewWidth, bool NewSign,
SourceLocation Loc,
unsigned DiagID) {
// Perform a conversion to the promoted condition type if needed.
if (NewWidth > Val.getBitWidth()) {
// If this is an extension, just do it.
Val = Val.extend(NewWidth);
Val.setIsSigned(NewSign);
// If the input was signed and negative and the output is
// unsigned, don't bother to warn: this is implementation-defined
// behavior.
// FIXME: Introduce a second, default-ignored warning for this case?
} else if (NewWidth < Val.getBitWidth()) {
// If this is a truncation, check for overflow.
llvm::APSInt ConvVal(Val);
ConvVal = ConvVal.trunc(NewWidth);
ConvVal.setIsSigned(NewSign);
ConvVal = ConvVal.extend(Val.getBitWidth());
ConvVal.setIsSigned(Val.isSigned());
if (ConvVal != Val)
Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10);
// Regardless of whether a diagnostic was emitted, really do the
// truncation.
Val = Val.trunc(NewWidth);
Val.setIsSigned(NewSign);
} else if (NewSign != Val.isSigned()) {
// Convert the sign to match the sign of the condition. This can cause
// overflow as well: unsigned(INTMIN)
// We don't diagnose this overflow, because it is implementation-defined
// behavior.
// FIXME: Introduce a second, default-ignored warning for this case?
llvm::APSInt OldVal(Val);
Val.setIsSigned(NewSign);
}
}
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();
}
StmtResult
Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond,
Decl *CondVar) {
ExprResult CondResult;
VarDecl *ConditionVar = 0;
if (CondVar) {
ConditionVar = cast<VarDecl>(CondVar);
CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false);
if (CondResult.isInvalid())
return StmtError();
Cond = CondResult.release();
}
if (!Cond)
return StmtError();
class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
Expr *Cond;
public:
SwitchConvertDiagnoser(Expr *Cond)
: ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true),
Cond(Cond) {}
virtual SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
QualType T) {
return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
}
virtual SemaDiagnosticBuilder diagnoseIncomplete(
Sema &S, SourceLocation Loc, QualType T) {
return S.Diag(Loc, diag::err_switch_incomplete_class_type)
<< T << Cond->getSourceRange();
}
virtual SemaDiagnosticBuilder diagnoseExplicitConv(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) {
return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
}
virtual SemaDiagnosticBuilder noteExplicitConv(
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) {
return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
<< ConvTy->isEnumeralType() << ConvTy;
}
virtual SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
QualType T) {
return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
}
virtual SemaDiagnosticBuilder noteAmbiguous(
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) {
return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
<< ConvTy->isEnumeralType() << ConvTy;
}
virtual SemaDiagnosticBuilder diagnoseConversion(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) {
llvm_unreachable("conversion functions are permitted");
}
} SwitchDiagnoser(Cond);
CondResult =
PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser);
if (CondResult.isInvalid()) return StmtError();
Cond = CondResult.take();
// C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
CondResult = UsualUnaryConversions(Cond);
if (CondResult.isInvalid()) return StmtError();
Cond = CondResult.take();
if (!CondVar) {
CondResult = ActOnFinishFullExpr(Cond, SwitchLoc);
if (CondResult.isInvalid())
return StmtError();
Cond = CondResult.take();
}
getCurFunction()->setHasBranchIntoScope();
SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond);
getCurFunction()->SwitchStack.push_back(SS);
return Owned(SS);
}
static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
if (Val.getBitWidth() < BitWidth)
Val = Val.extend(BitWidth);
else if (Val.getBitWidth() > BitWidth)
Val = Val.trunc(BitWidth);
Val.setIsSigned(IsSigned);
}
StmtResult
Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
Stmt *BodyStmt) {
SwitchStmt *SS = cast<SwitchStmt>(Switch);
assert(SS == getCurFunction()->SwitchStack.back() &&
"switch stack missing push/pop!");
SS->setBody(BodyStmt, SwitchLoc);
getCurFunction()->SwitchStack.pop_back();
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 before 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(CondTypeBeforePromotion);
bool CondIsSigned
= 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 = 0;
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.take();
} 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).take();
Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take();
}
// Convert the value to the same width/sign as the condition had prior to
// integral promotions.
//
// FIXME: This causes us to reject valid code:
// switch ((char)c) { case 256: case 0: return 0; }
// Here we claim there is a duplicated condition value, but there is not.
ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned,
Lo->getLocStart(),
diag::warn_case_value_overflow);
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
= CondExprBeforePromotion->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() ? CaseValStr.str() : PrevString);
else
Diag(CaseVals[i].second->getLHS()->getLocStart(),
diag::err_duplicate_case_differing_expr) <<
(PrevString.empty() ? CaseValStr.str() : PrevString) <<
(CurrString.empty() ? CaseValStr.str() : 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.take();
} else {
HiVal = Hi->EvaluateKnownConstInt(Context);
// If the RHS is not the same type as the condition, insert an
// implicit cast.
Hi = DefaultLvalueConversion(Hi).take();
Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take();
}
// Convert the value to the same width/sign as the condition.
ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned,
Hi->getLocStart(),
diag::warn_case_value_overflow);
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 = 0;
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) {
const EnumDecl *ED = ET->getDecl();
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 CaseVals.
for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin();
EDI != ED->enumerator_end(); ++EDI) {
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);
EnumValsTy::iterator EIend =
std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
// See which case values aren't in enum.
EnumValsTy::const_iterator EI = EnumVals.begin();
for (CaseValsTy::const_iterator CI = CaseVals.begin();
CI != CaseVals.end(); CI++) {
while (EI != EIend && EI->first < CI->first)
EI++;
if (EI == EIend || EI->first > CI->first)
Diag(CI->second->getLHS()->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() && EI != EIend; RI++) {
while (EI != EIend && EI->first < RI->first)
EI++;
if (EI == EIend || EI->first != RI->first) {
Diag(RI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum)
<< CondTypeBeforePromotion;
}
llvm::APSInt Hi =
RI->second->getRHS()->EvaluateKnownConstInt(Context);
AdjustAPSInt(Hi, CondWidth, CondIsSigned);
while (EI != EIend && EI->first < Hi)
EI++;
if (EI == EIend || EI->first != Hi)
Diag(RI->second->getRHS()->getExprLoc(), diag::warn_not_in_enum)
<< CondTypeBeforePromotion;
}
// Check which enum vals aren't in switch
CaseValsTy::const_iterator CI = CaseVals.begin();
CaseRangesTy::const_iterator RI = CaseRanges.begin();
bool hasCasesNotInSwitch = false;
SmallVector<DeclarationName,8> UnhandledNames;
for (EI = EnumVals.begin(); EI != EIend; EI++){
// Drop unneeded case values
llvm::APSInt CIVal;
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())
Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
// Produce a nice diagnostic if multiple values aren't handled.
switch (UnhandledNames.size()) {
case 0: break;
case 1:
Diag(CondExpr->getExprLoc(), TheDefaultStmt
? diag::warn_def_missing_case1 : diag::warn_missing_case1)
<< UnhandledNames[0];
break;
case 2:
Diag(CondExpr->getExprLoc(), TheDefaultStmt
? diag::warn_def_missing_case2 : diag::warn_missing_case2)
<< UnhandledNames[0] << UnhandledNames[1];
break;
case 3:
Diag(CondExpr->getExprLoc(), TheDefaultStmt
? diag::warn_def_missing_case3 : diag::warn_missing_case3)
<< UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
break;
default:
Diag(CondExpr->getExprLoc(), TheDefaultStmt
? diag::warn_def_missing_cases : diag::warn_missing_cases)
<< (unsigned)UnhandledNames.size()
<< UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
break;
}
if (!hasCasesNotInSwitch)
SS->setAllEnumCasesCovered();
}
}
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 Owned(SS);
}
void
Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
Expr *SrcExpr) {
if (Diags.getDiagnosticLevel(diag::warn_not_in_enum_assignment,
SrcExpr->getExprLoc()) ==
DiagnosticsEngine::Ignored)
return;
if (const EnumType *ET = DstType->getAs<EnumType>())
if (!Context.hasSameType(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();
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 (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin();
EDI != ED->enumerator_end(); ++EDI) {
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;
}
}
}
}
StmtResult
Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,
Decl *CondVar, Stmt *Body) {
ExprResult CondResult(Cond.release());
VarDecl *ConditionVar = 0;
if (CondVar) {
ConditionVar = cast<VarDecl>(CondVar);
CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true);
if (CondResult.isInvalid())
return StmtError();
}
Expr *ConditionExpr = CondResult.take();
if (!ConditionExpr)
return StmtError();
DiagnoseUnusedExprResult(Body);
if (isa<NullStmt>(Body))
getCurCompoundScope().setHasEmptyLoopBodies();
return Owned(new (Context) WhileStmt(Context, ConditionVar, ConditionExpr,
Body, WhileLoc));
}
StmtResult
Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
SourceLocation WhileLoc, SourceLocation CondLParen,
Expr *Cond, SourceLocation CondRParen) {
assert(Cond && "ActOnDoStmt(): missing expression");
ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc);
if (CondResult.isInvalid())
return StmtError();
Cond = CondResult.take();
CondResult = ActOnFinishFullExpr(Cond, DoLoc);
if (CondResult.isInvalid())
return StmtError();
Cond = CondResult.take();
DiagnoseUnusedExprResult(Body);
return Owned(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::SmallPtrSet<VarDecl*, 8> &Decls;
SmallVectorImpl<SourceRange> &Ranges;
bool Simple;
public:
typedef EvaluatedExprVisitor<DeclExtractor> Inherited;
DeclExtractor(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &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-evauluated
// context.
class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> {
llvm::SmallPtrSet<VarDecl*, 8> &Decls;
bool FoundDecl;
public:
typedef EvaluatedExprVisitor<DeclMatcher> Inherited;
DeclMatcher(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &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;
}
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.getDiagnosticLevel(diag::warn_variables_not_in_loop_body,
Second->getLocStart())
== DiagnosticsEngine::Ignored)
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::SmallPtrSet<VarDecl*, 8>::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::SmallPtrSet<VarDecl*, 8>::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 (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 statement is a subexpression.
class ContinueFinder : public EvaluatedExprVisitor<ContinueFinder> {
bool Found;
public:
ContinueFinder(Sema &S, Stmt* Body) :
Inherited(S.Context),
Found(false) {
Visit(Body);
}
typedef EvaluatedExprVisitor<ContinueFinder> Inherited;
void VisitContinueStmt(ContinueStmt* E) {
Found = true;
}
bool ContinueFound() { return Found; }
}; // end class ContinueFinder
// 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.getDiagnosticLevel(diag::warn_redundant_loop_iteration,
Third->getLocStart())
== DiagnosticsEngine::Ignored)
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 varaible.
if (LoopIncrement != LastIncrement ||
LoopDRE->getDecl() != LastDRE->getDecl()) return;
if (ContinueFinder(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
StmtResult
Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
Stmt *First, FullExprArg second, Decl *secondVar,
FullExprArg third,
SourceLocation RParenLoc, Stmt *Body) {
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 (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end();
DI!=DE; ++DI) {
VarDecl *VD = dyn_cast<VarDecl>(*DI);
if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage())
VD = 0;
if (VD == 0) {
Diag((*DI)->getLocation(), diag::err_non_local_variable_decl_in_for);
(*DI)->setInvalidDecl();
}
}
}
}
CheckForLoopConditionalStatement(*this, second.get(), third.get(), Body);
CheckForRedundantIteration(*this, third.get(), Body);
ExprResult SecondResult(second.release());
VarDecl *ConditionVar = 0;
if (secondVar) {
ConditionVar = cast<VarDecl>(secondVar);
SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true);
if (SecondResult.isInvalid())
return StmtError();
}
Expr *Third = third.release().takeAs<Expr>();
DiagnoseUnusedExprResult(First);
DiagnoseUnusedExprResult(Third);
DiagnoseUnusedExprResult(Body);
if (isa<NullStmt>(Body))
getCurCompoundScope().setHasEmptyLoopBodies();
return Owned(new (Context) ForStmt(Context, First,
SecondResult.take(), ConditionVar,
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.take();
ExprResult FullExpr = ActOnFinishFullExpr(E);
if (FullExpr.isInvalid())
return StmtError();
return StmtResult(static_cast<Stmt*>(FullExpr.take()));
}
ExprResult
Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
if (!collection)
return ExprError();
// Bail out early if we've got a type-dependent expression.
if (collection->isTypeDependent()) return Owned(collection);
// Perform normal l-value conversion.
ExprResult result = DefaultFunctionArrayLvalueConversion(collection);
if (result.isInvalid())
return ExprError();
collection = result.take();
// 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 &&
RequireCompleteType(forLoc, QualType(objectType, 0),
getLangOpts().ObjCAutoRefCount
? diag::err_arc_collection_forward
: 0,
collection)) {
// 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 = 0;
// 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 Owned(collection);
}
StmtResult
Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
Stmt *First, Expr *collection,
SourceLocation RParenLoc) {
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 (ActiveTemplateInstantiations.empty()) {
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.take());
if (CollectionExprResult.isInvalid())
return StmtError();
return Owned(new (Context) ObjCForCollectionStmt(First,
CollectionExprResult.take(), 0,
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) {
// 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,
/*TypeMayContainAuto=*/false);
SemaRef.FinalizeDeclaration(Decl);
SemaRef.CurContext->addHiddenDecl(Decl);
return false;
}
namespace {
/// 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,
Sema::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>() != 0;
}
/// 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(SourceLocation ForLoc,
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();
}
// 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(llvm::MutableArrayRef<Decl *>((Decl **)&RangeVar, 1),
/*TypeMayContainAuto=*/ false);
StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
if (RangeDecl.isInvalid()) {
LoopVar->setInvalidDecl();
return StmtError();
}
return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(),
/*BeginEndDecl=*/0, /*Cond=*/0, /*Inc=*/0, 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, Scope *S,
Expr *BeginRange, Expr *EndRange,
QualType RangeType,
VarDecl *BeginVar,
VarDecl *EndVar,
SourceLocation ColonLoc,
OverloadCandidateSet *CandidateSet,
ExprResult *BeginExpr,
ExprResult *EndExpr,
Sema::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() ? Sema::BEF_end : Sema::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 = Sema::BEF_begin;
Sema::ForRangeStatus RangeStatus =
SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, BeginVar,
Sema::BEF_begin, BeginNameInfo,
BeginMemberLookup, CandidateSet,
BeginRange, BeginExpr);
if (RangeStatus != Sema::FRS_Success)
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 = Sema::BEF_end;
RangeStatus =
SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, EndVar,
Sema::BEF_end, EndNameInfo,
EndMemberLookup, CandidateSet,
EndRange, EndExpr);
if (RangeStatus != Sema::FRS_Success)
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,
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(ForLoc, 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(ForLoc, 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 ColonLoc,
Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond,
Expr *Inc, Stmt *LoopVarDecl,
SourceLocation RParenLoc, BuildForRangeKind Kind) {
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 BeginEndDecl = BeginEnd;
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 (!BeginEndDecl.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 = Owned(IntegerLiteral::Create(Context, CAT->getSize(),
Context.getPointerDiffType(),
RangeLoc));
else if (const VariableArrayType *VAT =
dyn_cast<VariableArrayType>(UnqAT))
BoundExpr = VAT->getSizeExpr();
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);
Sema::BeginEndFunction BEFFailure;
ForRangeStatus RangeStatus =
BuildNonArrayForRange(*this, S, 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,
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.
QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
if (!Context.hasSameType(BeginType, EndType)) {
Diag(RangeLoc, diag::err_for_range_begin_end_types_differ)
<< BeginType << EndType;
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
}
Decl *BeginEndDecls[] = { BeginVar, EndVar };
// Claim the type doesn't contain auto: we've already done the checking.
DeclGroupPtrTy BeginEndGroup =
BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *>(BeginEndDecls, 2),
/*TypeMayContainAuto=*/ false);
BeginEndDecl = ActOnDeclStmt(BeginEndGroup, 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());
NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get());
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());
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,
/*TypeMayContainAuto=*/true);
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 Owned(new (Context) CXXForRangeStmt(RangeDS,
cast_or_null<DeclStmt>(BeginEndDecl.get()),
NotEqExpr.take(), IncrExpr.take(),
LoopVarDS, /*Body=*/0, ForLoc,
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;
}
/// 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);
return S;
}
StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
SourceLocation LabelLoc,
LabelDecl *TheDecl) {
getCurFunction()->setHasBranchIntoScope();
TheDecl->markUsed(Context);
return Owned(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 = Owned(E);
AssignConvertType ConvTy =
CheckSingleAssignmentConstraints(DestTy, ExprRes);
if (ExprRes.isInvalid())
return StmtError();
E = ExprRes.take();
if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
return StmtError();
}
ExprResult ExprRes = ActOnFinishFullExpr(E);
if (ExprRes.isInvalid())
return StmtError();
E = ExprRes.take();
getCurFunction()->setHasIndirectGoto();
return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E));
}
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));
}
return Owned(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));
}
return Owned(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 AllowFunctionParameter Whether we allow function parameters to
/// be considered NRVO candidates. C++ prohibits this 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.
const VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType,
Expr *E,
bool AllowFunctionParameter) {
QualType ExprType = E->getType();
// - in a return statement in a function with ...
// ... a class return type ...
if (!ReturnType.isNull()) {
if (!ReturnType->isRecordType())
return 0;
// ... the same cv-unqualified type as the function return type ...
if (!Context.hasSameUnqualifiedType(ReturnType, ExprType))
return 0;
}
// ... the expression is the name of a non-volatile automatic object
// (other than a function or catch-clause parameter)) ...
const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
if (!DR || DR->refersToEnclosingLocal())
return 0;
const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
if (!VD)
return 0;
// ...object (other than a function or catch-clause parameter)...
if (VD->getKind() != Decl::Var &&
!(AllowFunctionParameter && VD->getKind() == Decl::ParmVar))
return 0;
if (VD->isExceptionVariable()) return 0;
// ...automatic...
if (!VD->hasLocalStorage()) return 0;
// ...non-volatile...
if (VD->getType().isVolatileQualified()) return 0;
if (VD->getType()->isReferenceType()) return 0;
// __block variables can't be allocated in a way that permits NRVO.
if (VD->hasAttr<BlocksAttr>()) return 0;
// Variables with higher required alignment than their type's ABI
// alignment cannot use NRVO.
if (VD->hasAttr<AlignedAttr>() &&
Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType()))
return 0;
return VD;
}
/// \brief Perform the initialization of a potentially-movable value, which
/// is the result of return value.
///
/// This routine implements C++0x [class.copy]p33, 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++0x [class.copy]p33:
// When the criteria for elision of a copy operation are met or would
// be met save for the fact that the source object is a function
// parameter, and the object to be copied is designated by an lvalue,
// 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 || getCopyElisionCandidate(ResultType, Value, true))) {
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 overload resolution fails, 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 (Seq) {
for (InitializationSequence::step_iterator Step = Seq.step_begin(),
StepEnd = Seq.step_end();
Step != StepEnd; ++Step) {
if (Step->Kind != InitializationSequence::SK_ConstructorInitialization)
continue;
CXXConstructorDecl *Constructor
= cast<CXXConstructorDecl>(Step->Function.Function);
const RValueReferenceType *RRefType
= Constructor->getParamDecl(0)->getType()
->getAs<RValueReferenceType>();
// If we don't meet the criteria, break out now.
if (!RRefType ||
!Context.hasSameUnqualifiedType(RRefType->getPointeeType(),
Context.getTypeDeclType(Constructor->getParent())))
break;
// Promote "AsRvalue" to the heap, since we now need this
// expression node to persist.
Value = ImplicitCastExpr::Create(Context, Value->getType(),
CK_NoOp, Value, 0, 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->getResultType()->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);
if (CurLambda && hasDeducedReturnType(CurLambda->CallOperator)) {
// 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->getResultType();
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->getResultType();
} 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.take();
if (!CurContext->isDependentContext())
FnRetType = RetValExp->getType();
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 = 0;
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 = 0;
}
}
} 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 != 0);
ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
FnRetType, RetValExp);
if (Res.isInvalid()) {
// FIXME: Cleanup temporaries here, anyway?
return StmtError();
}
RetValExp = Res.take();
CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
}
if (RetValExp) {
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
if (ER.isInvalid())
return StmtError();
RetValExp = ER.take();
}
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 ||
(getLangOpts().CPlusPlus && FnRetType->isRecordType() &&
!CurContext->isDependentContext()))
FunctionScopes.back()->Returns.push_back(Result);
return Owned(Result);
}
/// 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 = FD->getTypeSourceInfo()->getTypeLoc().
IgnoreParens().castAs<FunctionProtoTypeLoc>().getResultLoc();
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;
} else if (RetExpr) {
// If the deduction is for a return statement and the initializer is
// a braced-init-list, the program is ill-formed.
if (isa<InitListExpr>(RetExpr)) {
Diag(RetExpr->getExprLoc(), diag::err_auto_fn_return_init_list);
return true;
}
// 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;
} 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.
if (AT->isDeduced() && !FD->isInvalidDecl()) {
AutoType *NewAT = Deduced->getContainedAutoType();
if (!FD->isDependentContext() &&
!Context.hasSameType(AT->getDeducedType(), NewAT->getDeducedType())) {
const LambdaScopeInfo *LambdaSI = getCurLambda();
if (LambdaSI && LambdaSI->HasImplicitReturnType) {
Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
<< NewAT->getDeducedType() << AT->getDeducedType()
<< true /*IsLambda*/;
} else {
Diag(ReturnLoc, diag::err_auto_fn_different_deductions)
<< (AT->isDecltypeAuto() ? 1 : 0)
<< NewAT->getDeducedType() << AT->getDeducedType();
}
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) {
// Check for unexpanded parameter packs.
if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
return StmtError();
if (isa<CapturingScopeInfo>(getCurFunction()))
return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
QualType FnRetType;
QualType RelatedRetType;
if (const FunctionDecl *FD = getCurFunctionDecl()) {
FnRetType = FD->getResultType();
if (FD->isNoReturn())
Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
<< FD->getDeclName();
} else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
FnRetType = MD->getResultType();
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();
// FIXME: Add a flag to the ScopeInfo to indicate whether we're performing
// deduction.
if (getLangOpts().CPlusPlus1y) {
if (AutoType *AT = FnRetType->getContainedAutoType()) {
FunctionDecl *FD = cast<FunctionDecl>(CurContext);
if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
FD->setInvalidDecl();
return StmtError();
} else {
FnRetType = FD->getResultType();
}
}
}
bool HasDependentReturnType = FnRetType->isDependentType();
ReturnStmt *Result = 0;
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 = 0;
} else if (!RetValExp->isTypeDependent()) {
// C99 6.8.6.4p1 (ext_ since GCC warns)
unsigned D = diag::ext_return_has_expr;
if (RetValExp->getType()->isVoidType())
D = diag::ext_return_has_void_expr;
else {
ExprResult Result = Owned(RetValExp);
Result = IgnoredValueConversions(Result.take());
if (Result.isInvalid())
return StmtError();
RetValExp = Result.take();
RetValExp = ImpCastExprToType(RetValExp,
Context.VoidTy, CK_ToVoid).take();
}
// return (some void expression); is legal in C++.
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.take();
}
}
Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0);
} else if (!RetValExp && !HasDependentReturnType) {
unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4
// C99 6.8.6.4p1 (ext_ since GCC warns)
if (getLangOpts().C99) DiagID = diag::ext_return_missing_expr;
if (FunctionDecl *FD = getCurFunctionDecl())
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 = 0;
if (!HasDependentReturnType && !RetValExp->isTypeDependent()) {
// we have a non-void function with an expression, continue checking
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.
NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
RetType,
NRVOCandidate != 0);
ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
RetType, RetValExp);
if (Res.isInvalid()) {
// FIXME: Clean up temporaries here anyway?
return StmtError();
}
RetValExp = Res.takeAs<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.takeAs<Expr>();
}
CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
}
if (RetValExp) {
ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
if (ER.isInvalid())
return StmtError();
RetValExp = ER.take();
}
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 (getLangOpts().CPlusPlus && FnRetType->isRecordType() &&
!CurContext->isDependentContext())
FunctionScopes.back()->Returns.push_back(Result);
return Owned(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 Owned(new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body));
}
StmtResult
Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
return Owned(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 Owned(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.take());
if (Result.isInvalid())
return StmtError();
Throw = Result.take();
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::error_objc_throw_expects_object)
<< Throw->getType() << Throw->getSourceRange());
}
}
return Owned(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 much 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::error_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.take();
// 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())
return Diag(atLoc, diag::error_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 Owned(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 Owned(new (Context) CXXCatchStmt(CatchLoc,
cast_or_null<VarDecl>(ExDecl),
HandlerBlock));
}
StmtResult
Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) {
getCurFunction()->setHasBranchProtectedScope();
return Owned(new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body));
}
namespace {
class TypeWithHandler {
QualType t;
CXXCatchStmt *stmt;
public:
TypeWithHandler(const QualType &type, CXXCatchStmt *statement)
: t(type), stmt(statement) {}
// An arbitrary order is fine as long as it places identical
// types next to each other.
bool operator<(const TypeWithHandler &y) const {
if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr())
return true;
if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr())
return false;
else
return getTypeSpecStartLoc() < y.getTypeSpecStartLoc();
}
bool operator==(const TypeWithHandler& other) const {
return t == other.t;
}
CXXCatchStmt *getCatchStmt() const { return stmt; }
SourceLocation getTypeSpecStartLoc() const {
return stmt->getExceptionDecl()->getTypeSpecStartLoc();
}
};
}
/// 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";
const unsigned NumHandlers = Handlers.size();
assert(NumHandlers > 0 &&
"The parser shouldn't call this if there are no handlers.");
SmallVector<TypeWithHandler, 8> TypesWithHandlers;
for (unsigned i = 0; i < NumHandlers; ++i) {
CXXCatchStmt *Handler = cast<CXXCatchStmt>(Handlers[i]);
if (!Handler->getExceptionDecl()) {
if (i < NumHandlers - 1)
return StmtError(Diag(Handler->getLocStart(),
diag::err_early_catch_all));
continue;
}
const QualType CaughtType = Handler->getCaughtType();
const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType);
TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler));
}
// Detect handlers for the same type as an earlier one.
if (NumHandlers > 1) {
llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end());
TypeWithHandler prev = TypesWithHandlers[0];
for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) {
TypeWithHandler curr = TypesWithHandlers[i];
if (curr == prev) {
Diag(curr.getTypeSpecStartLoc(),
diag::warn_exception_caught_by_earlier_handler)
<< curr.getCatchStmt()->getCaughtType().getAsString();
Diag(prev.getTypeSpecStartLoc(),
diag::note_previous_exception_handler)
<< prev.getCatchStmt()->getCaughtType().getAsString();
}
prev = curr;
}
}
getCurFunction()->setHasBranchProtectedScope();
// FIXME: We should detect handlers that cannot catch anything because an
// earlier handler catches a superclass. Need to find a method that is not
// quadratic for this.
// Neither of these are explicitly forbidden, but every compiler detects them
// and warns.
return Owned(CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers));
}
StmtResult
Sema::ActOnSEHTryBlock(bool IsCXXTry,
SourceLocation TryLoc,
Stmt *TryBlock,
Stmt *Handler) {
assert(TryBlock && Handler);
getCurFunction()->setHasBranchProtectedScope();
return Owned(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 Owned(SEHExceptStmt::Create(Context,Loc,FilterExpr,Block));
}
StmtResult
Sema::ActOnSEHFinallyBlock(SourceLocation Loc,
Stmt *Block) {
assert(Block);
return Owned(SEHFinallyStmt::Create(Context,Loc,Block));
}
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 = 0;
if (getLangOpts().CPlusPlus)
RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0);
else
RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0);
DC->addDecl(RD);
RD->setImplicit();
RD->startDefinition();
CD = CapturedDecl::Create(Context, CurContext, NumParams);
DC->addDecl(CD);
// Build the context parameter
assert(NumParams > 0 && "CapturedStmt requires context parameter");
DC = CapturedDecl::castToDeclContext(CD);
IdentifierInfo *VarName = &Context.Idents.get("__context");
QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
ImplicitParamDecl *Param
= ImplicitParamDecl::Create(Context, DC, Loc, VarName, ParamType);
DC->addDecl(Param);
CD->setContextParam(Param);
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;
}
assert(Cap->isReferenceCapture() &&
"non-reference capture not yet implemented");
Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
CapturedStmt::VCK_ByRef,
Cap->getVariable()));
CaptureInits.push_back(Cap->getInitExpr());
}
}
void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
CapturedRegionKind Kind,
unsigned NumParams) {
CapturedDecl *CD = 0;
RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams);
// Enter the capturing scope for this captured region.
PushCapturedRegionScope(CurScope, CD, RD, Kind);
if (CurScope)
PushDeclContext(CurScope, CD);
else
CurContext = CD;
PushExpressionEvaluationContext(PotentiallyEvaluated);
}
void Sema::ActOnCapturedRegionError() {
DiscardCleanupsInEvaluationContext();
PopExpressionEvaluationContext();
CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
RecordDecl *Record = RSI->TheRecordDecl;
Record->setInvalidDecl();
SmallVector<Decl*, 4> Fields;
for (RecordDecl::field_iterator I = Record->field_begin(),
E = Record->field_end(); I != E; ++I)
Fields.push_back(*I);
ActOnFields(/*Scope=*/0, Record->getLocation(), Record, Fields,
SourceLocation(), SourceLocation(), /*AttributeList=*/0);
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,
RSI->CapRegionKind, Captures,
CaptureInits, CD, RD);
CD->setBody(Res->getCapturedStmt());
RD->completeDefinition();
DiscardCleanupsInEvaluationContext();
PopExpressionEvaluationContext();
PopDeclContext();
PopFunctionScopeInfo();
return Owned(Res);
}
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