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diff --git a/contrib/llvm/tools/clang/lib/Sema/AnalysisBasedWarnings.cpp b/contrib/llvm/tools/clang/lib/Sema/AnalysisBasedWarnings.cpp
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+//=- AnalysisBasedWarnings.cpp - Sema warnings based on libAnalysis -*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines analysis_warnings::[Policy,Executor].
+// Together they are used by Sema to issue warnings based on inexpensive
+// static analysis algorithms in libAnalysis.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Sema/AnalysisBasedWarnings.h"
+#include "clang/Sema/SemaInternal.h"
+#include "clang/Sema/ScopeInfo.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/StmtObjC.h"
+#include "clang/AST/StmtCXX.h"
+#include "clang/AST/EvaluatedExprVisitor.h"
+#include "clang/Analysis/AnalysisContext.h"
+#include "clang/Analysis/CFG.h"
+#include "clang/Analysis/Analyses/ReachableCode.h"
+#include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
+#include "clang/Analysis/CFGStmtMap.h"
+#include "clang/Analysis/Analyses/UninitializedValues.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/Support/Casting.h"
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// Unreachable code analysis.
+//===----------------------------------------------------------------------===//
+
+namespace {
+ class UnreachableCodeHandler : public reachable_code::Callback {
+ Sema &S;
+ public:
+ UnreachableCodeHandler(Sema &s) : S(s) {}
+
+ void HandleUnreachable(SourceLocation L, SourceRange R1, SourceRange R2) {
+ S.Diag(L, diag::warn_unreachable) << R1 << R2;
+ }
+ };
+}
+
+/// CheckUnreachable - Check for unreachable code.
+static void CheckUnreachable(Sema &S, AnalysisContext &AC) {
+ UnreachableCodeHandler UC(S);
+ reachable_code::FindUnreachableCode(AC, UC);
+}
+
+//===----------------------------------------------------------------------===//
+// Check for missing return value.
+//===----------------------------------------------------------------------===//
+
+enum ControlFlowKind {
+ UnknownFallThrough,
+ NeverFallThrough,
+ MaybeFallThrough,
+ AlwaysFallThrough,
+ NeverFallThroughOrReturn
+};
+
+/// CheckFallThrough - Check that we don't fall off the end of a
+/// Statement that should return a value.
+///
+/// \returns AlwaysFallThrough iff we always fall off the end of the statement,
+/// MaybeFallThrough iff we might or might not fall off the end,
+/// NeverFallThroughOrReturn iff we never fall off the end of the statement or
+/// return. We assume NeverFallThrough iff we never fall off the end of the
+/// statement but we may return. We assume that functions not marked noreturn
+/// will return.
+static ControlFlowKind CheckFallThrough(AnalysisContext &AC) {
+ CFG *cfg = AC.getCFG();
+ if (cfg == 0) return UnknownFallThrough;
+
+ // The CFG leaves in dead things, and we don't want the dead code paths to
+ // confuse us, so we mark all live things first.
+ llvm::BitVector live(cfg->getNumBlockIDs());
+ unsigned count = reachable_code::ScanReachableFromBlock(cfg->getEntry(),
+ live);
+
+ bool AddEHEdges = AC.getAddEHEdges();
+ if (!AddEHEdges && count != cfg->getNumBlockIDs())
+ // When there are things remaining dead, and we didn't add EH edges
+ // from CallExprs to the catch clauses, we have to go back and
+ // mark them as live.
+ for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) {
+ CFGBlock &b = **I;
+ if (!live[b.getBlockID()]) {
+ if (b.pred_begin() == b.pred_end()) {
+ if (b.getTerminator() && isa<CXXTryStmt>(b.getTerminator()))
+ // When not adding EH edges from calls, catch clauses
+ // can otherwise seem dead. Avoid noting them as dead.
+ count += reachable_code::ScanReachableFromBlock(b, live);
+ continue;
+ }
+ }
+ }
+
+ // Now we know what is live, we check the live precessors of the exit block
+ // and look for fall through paths, being careful to ignore normal returns,
+ // and exceptional paths.
+ bool HasLiveReturn = false;
+ bool HasFakeEdge = false;
+ bool HasPlainEdge = false;
+ bool HasAbnormalEdge = false;
+
+ // Ignore default cases that aren't likely to be reachable because all
+ // enums in a switch(X) have explicit case statements.
+ CFGBlock::FilterOptions FO;
+ FO.IgnoreDefaultsWithCoveredEnums = 1;
+
+ for (CFGBlock::filtered_pred_iterator
+ I = cfg->getExit().filtered_pred_start_end(FO); I.hasMore(); ++I) {
+ const CFGBlock& B = **I;
+ if (!live[B.getBlockID()])
+ continue;
+
+ // Destructors can appear after the 'return' in the CFG. This is
+ // normal. We need to look pass the destructors for the return
+ // statement (if it exists).
+ CFGBlock::const_reverse_iterator ri = B.rbegin(), re = B.rend();
+ bool hasNoReturnDtor = false;
+
+ for ( ; ri != re ; ++ri) {
+ CFGElement CE = *ri;
+
+ // FIXME: The right solution is to just sever the edges in the
+ // CFG itself.
+ if (const CFGImplicitDtor *iDtor = ri->getAs<CFGImplicitDtor>())
+ if (iDtor->isNoReturn(AC.getASTContext())) {
+ hasNoReturnDtor = true;
+ HasFakeEdge = true;
+ break;
+ }
+
+ if (isa<CFGStmt>(CE))
+ break;
+ }
+
+ if (hasNoReturnDtor)
+ continue;
+
+ // No more CFGElements in the block?
+ if (ri == re) {
+ if (B.getTerminator() && isa<CXXTryStmt>(B.getTerminator())) {
+ HasAbnormalEdge = true;
+ continue;
+ }
+ // A labeled empty statement, or the entry block...
+ HasPlainEdge = true;
+ continue;
+ }
+
+ CFGStmt CS = cast<CFGStmt>(*ri);
+ Stmt *S = CS.getStmt();
+ if (isa<ReturnStmt>(S)) {
+ HasLiveReturn = true;
+ continue;
+ }
+ if (isa<ObjCAtThrowStmt>(S)) {
+ HasFakeEdge = true;
+ continue;
+ }
+ if (isa<CXXThrowExpr>(S)) {
+ HasFakeEdge = true;
+ continue;
+ }
+ if (const AsmStmt *AS = dyn_cast<AsmStmt>(S)) {
+ if (AS->isMSAsm()) {
+ HasFakeEdge = true;
+ HasLiveReturn = true;
+ continue;
+ }
+ }
+ if (isa<CXXTryStmt>(S)) {
+ HasAbnormalEdge = true;
+ continue;
+ }
+
+ bool NoReturnEdge = false;
+ if (CallExpr *C = dyn_cast<CallExpr>(S)) {
+ if (std::find(B.succ_begin(), B.succ_end(), &cfg->getExit())
+ == B.succ_end()) {
+ HasAbnormalEdge = true;
+ continue;
+ }
+ Expr *CEE = C->getCallee()->IgnoreParenCasts();
+ if (getFunctionExtInfo(CEE->getType()).getNoReturn()) {
+ NoReturnEdge = true;
+ HasFakeEdge = true;
+ } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) {
+ ValueDecl *VD = DRE->getDecl();
+ if (VD->hasAttr<NoReturnAttr>()) {
+ NoReturnEdge = true;
+ HasFakeEdge = true;
+ }
+ }
+ }
+ // FIXME: Add noreturn message sends.
+ if (NoReturnEdge == false)
+ HasPlainEdge = true;
+ }
+ if (!HasPlainEdge) {
+ if (HasLiveReturn)
+ return NeverFallThrough;
+ return NeverFallThroughOrReturn;
+ }
+ if (HasAbnormalEdge || HasFakeEdge || HasLiveReturn)
+ return MaybeFallThrough;
+ // This says AlwaysFallThrough for calls to functions that are not marked
+ // noreturn, that don't return. If people would like this warning to be more
+ // accurate, such functions should be marked as noreturn.
+ return AlwaysFallThrough;
+}
+
+namespace {
+
+struct CheckFallThroughDiagnostics {
+ unsigned diag_MaybeFallThrough_HasNoReturn;
+ unsigned diag_MaybeFallThrough_ReturnsNonVoid;
+ unsigned diag_AlwaysFallThrough_HasNoReturn;
+ unsigned diag_AlwaysFallThrough_ReturnsNonVoid;
+ unsigned diag_NeverFallThroughOrReturn;
+ bool funMode;
+ SourceLocation FuncLoc;
+
+ static CheckFallThroughDiagnostics MakeForFunction(const Decl *Func) {
+ CheckFallThroughDiagnostics D;
+ D.FuncLoc = Func->getLocation();
+ D.diag_MaybeFallThrough_HasNoReturn =
+ diag::warn_falloff_noreturn_function;
+ D.diag_MaybeFallThrough_ReturnsNonVoid =
+ diag::warn_maybe_falloff_nonvoid_function;
+ D.diag_AlwaysFallThrough_HasNoReturn =
+ diag::warn_falloff_noreturn_function;
+ D.diag_AlwaysFallThrough_ReturnsNonVoid =
+ diag::warn_falloff_nonvoid_function;
+
+ // Don't suggest that virtual functions be marked "noreturn", since they
+ // might be overridden by non-noreturn functions.
+ bool isVirtualMethod = false;
+ if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Func))
+ isVirtualMethod = Method->isVirtual();
+
+ if (!isVirtualMethod)
+ D.diag_NeverFallThroughOrReturn =
+ diag::warn_suggest_noreturn_function;
+ else
+ D.diag_NeverFallThroughOrReturn = 0;
+
+ D.funMode = true;
+ return D;
+ }
+
+ static CheckFallThroughDiagnostics MakeForBlock() {
+ CheckFallThroughDiagnostics D;
+ D.diag_MaybeFallThrough_HasNoReturn =
+ diag::err_noreturn_block_has_return_expr;
+ D.diag_MaybeFallThrough_ReturnsNonVoid =
+ diag::err_maybe_falloff_nonvoid_block;
+ D.diag_AlwaysFallThrough_HasNoReturn =
+ diag::err_noreturn_block_has_return_expr;
+ D.diag_AlwaysFallThrough_ReturnsNonVoid =
+ diag::err_falloff_nonvoid_block;
+ D.diag_NeverFallThroughOrReturn =
+ diag::warn_suggest_noreturn_block;
+ D.funMode = false;
+ return D;
+ }
+
+ bool checkDiagnostics(Diagnostic &D, bool ReturnsVoid,
+ bool HasNoReturn) const {
+ if (funMode) {
+ return (ReturnsVoid ||
+ D.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function,
+ FuncLoc) == Diagnostic::Ignored)
+ && (!HasNoReturn ||
+ D.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr,
+ FuncLoc) == Diagnostic::Ignored)
+ && (!ReturnsVoid ||
+ D.getDiagnosticLevel(diag::warn_suggest_noreturn_block, FuncLoc)
+ == Diagnostic::Ignored);
+ }
+
+ // For blocks.
+ return ReturnsVoid && !HasNoReturn
+ && (!ReturnsVoid ||
+ D.getDiagnosticLevel(diag::warn_suggest_noreturn_block, FuncLoc)
+ == Diagnostic::Ignored);
+ }
+};
+
+}
+
+/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a
+/// function that should return a value. Check that we don't fall off the end
+/// of a noreturn function. We assume that functions and blocks not marked
+/// noreturn will return.
+static void CheckFallThroughForBody(Sema &S, const Decl *D, const Stmt *Body,
+ const BlockExpr *blkExpr,
+ const CheckFallThroughDiagnostics& CD,
+ AnalysisContext &AC) {
+
+ bool ReturnsVoid = false;
+ bool HasNoReturn = false;
+
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+ ReturnsVoid = FD->getResultType()->isVoidType();
+ HasNoReturn = FD->hasAttr<NoReturnAttr>() ||
+ FD->getType()->getAs<FunctionType>()->getNoReturnAttr();
+ }
+ else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
+ ReturnsVoid = MD->getResultType()->isVoidType();
+ HasNoReturn = MD->hasAttr<NoReturnAttr>();
+ }
+ else if (isa<BlockDecl>(D)) {
+ QualType BlockTy = blkExpr->getType();
+ if (const FunctionType *FT =
+ BlockTy->getPointeeType()->getAs<FunctionType>()) {
+ if (FT->getResultType()->isVoidType())
+ ReturnsVoid = true;
+ if (FT->getNoReturnAttr())
+ HasNoReturn = true;
+ }
+ }
+
+ Diagnostic &Diags = S.getDiagnostics();
+
+ // Short circuit for compilation speed.
+ if (CD.checkDiagnostics(Diags, ReturnsVoid, HasNoReturn))
+ return;
+
+ // FIXME: Function try block
+ if (const CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) {
+ switch (CheckFallThrough(AC)) {
+ case UnknownFallThrough:
+ break;
+
+ case MaybeFallThrough:
+ if (HasNoReturn)
+ S.Diag(Compound->getRBracLoc(),
+ CD.diag_MaybeFallThrough_HasNoReturn);
+ else if (!ReturnsVoid)
+ S.Diag(Compound->getRBracLoc(),
+ CD.diag_MaybeFallThrough_ReturnsNonVoid);
+ break;
+ case AlwaysFallThrough:
+ if (HasNoReturn)
+ S.Diag(Compound->getRBracLoc(),
+ CD.diag_AlwaysFallThrough_HasNoReturn);
+ else if (!ReturnsVoid)
+ S.Diag(Compound->getRBracLoc(),
+ CD.diag_AlwaysFallThrough_ReturnsNonVoid);
+ break;
+ case NeverFallThroughOrReturn:
+ if (ReturnsVoid && !HasNoReturn && CD.diag_NeverFallThroughOrReturn)
+ S.Diag(Compound->getLBracLoc(),
+ CD.diag_NeverFallThroughOrReturn);
+ break;
+ case NeverFallThrough:
+ break;
+ }
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// -Wuninitialized
+//===----------------------------------------------------------------------===//
+
+namespace {
+/// ContainsReference - A visitor class to search for references to
+/// a particular declaration (the needle) within any evaluated component of an
+/// expression (recursively).
+class ContainsReference : public EvaluatedExprVisitor<ContainsReference> {
+ bool FoundReference;
+ const DeclRefExpr *Needle;
+
+public:
+ ContainsReference(ASTContext &Context, const DeclRefExpr *Needle)
+ : EvaluatedExprVisitor<ContainsReference>(Context),
+ FoundReference(false), Needle(Needle) {}
+
+ void VisitExpr(Expr *E) {
+ // Stop evaluating if we already have a reference.
+ if (FoundReference)
+ return;
+
+ EvaluatedExprVisitor<ContainsReference>::VisitExpr(E);
+ }
+
+ void VisitDeclRefExpr(DeclRefExpr *E) {
+ if (E == Needle)
+ FoundReference = true;
+ else
+ EvaluatedExprVisitor<ContainsReference>::VisitDeclRefExpr(E);
+ }
+
+ bool doesContainReference() const { return FoundReference; }
+};
+}
+
+/// DiagnoseUninitializedUse -- Helper function for diagnosing uses of an
+/// uninitialized variable. This manages the different forms of diagnostic
+/// emitted for particular types of uses. Returns true if the use was diagnosed
+/// as a warning. If a pariticular use is one we omit warnings for, returns
+/// false.
+static bool DiagnoseUninitializedUse(Sema &S, const VarDecl *VD,
+ const Expr *E, bool isAlwaysUninit) {
+ bool isSelfInit = false;
+
+ if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
+ if (isAlwaysUninit) {
+ // Inspect the initializer of the variable declaration which is
+ // being referenced prior to its initialization. We emit
+ // specialized diagnostics for self-initialization, and we
+ // specifically avoid warning about self references which take the
+ // form of:
+ //
+ // int x = x;
+ //
+ // This is used to indicate to GCC that 'x' is intentionally left
+ // uninitialized. Proven code paths which access 'x' in
+ // an uninitialized state after this will still warn.
+ //
+ // TODO: Should we suppress maybe-uninitialized warnings for
+ // variables initialized in this way?
+ if (const Expr *Initializer = VD->getInit()) {
+ if (DRE == Initializer->IgnoreParenImpCasts())
+ return false;
+
+ ContainsReference CR(S.Context, DRE);
+ CR.Visit(const_cast<Expr*>(Initializer));
+ isSelfInit = CR.doesContainReference();
+ }
+ if (isSelfInit) {
+ S.Diag(DRE->getLocStart(),
+ diag::warn_uninit_self_reference_in_init)
+ << VD->getDeclName() << VD->getLocation() << DRE->getSourceRange();
+ } else {
+ S.Diag(DRE->getLocStart(), diag::warn_uninit_var)
+ << VD->getDeclName() << DRE->getSourceRange();
+ }
+ } else {
+ S.Diag(DRE->getLocStart(), diag::warn_maybe_uninit_var)
+ << VD->getDeclName() << DRE->getSourceRange();
+ }
+ } else {
+ const BlockExpr *BE = cast<BlockExpr>(E);
+ S.Diag(BE->getLocStart(),
+ isAlwaysUninit ? diag::warn_uninit_var_captured_by_block
+ : diag::warn_maybe_uninit_var_captured_by_block)
+ << VD->getDeclName();
+ }
+
+ // Report where the variable was declared when the use wasn't within
+ // the initializer of that declaration.
+ if (!isSelfInit)
+ S.Diag(VD->getLocStart(), diag::note_uninit_var_def)
+ << VD->getDeclName();
+
+ return true;
+}
+
+static void SuggestInitializationFixit(Sema &S, const VarDecl *VD) {
+ // Don't issue a fixit if there is already an initializer.
+ if (VD->getInit())
+ return;
+
+ // Suggest possible initialization (if any).
+ const char *initialization = 0;
+ QualType VariableTy = VD->getType().getCanonicalType();
+
+ if (VariableTy->getAs<ObjCObjectPointerType>()) {
+ // Check if 'nil' is defined.
+ if (S.PP.getMacroInfo(&S.getASTContext().Idents.get("nil")))
+ initialization = " = nil";
+ else
+ initialization = " = 0";
+ }
+ else if (VariableTy->isRealFloatingType())
+ initialization = " = 0.0";
+ else if (VariableTy->isBooleanType() && S.Context.getLangOptions().CPlusPlus)
+ initialization = " = false";
+ else if (VariableTy->isEnumeralType())
+ return;
+ else if (VariableTy->isScalarType())
+ initialization = " = 0";
+
+ if (initialization) {
+ SourceLocation loc = S.PP.getLocForEndOfToken(VD->getLocEnd());
+ S.Diag(loc, diag::note_var_fixit_add_initialization)
+ << FixItHint::CreateInsertion(loc, initialization);
+ }
+}
+
+typedef std::pair<const Expr*, bool> UninitUse;
+
+namespace {
+struct SLocSort {
+ bool operator()(const UninitUse &a, const UninitUse &b) {
+ SourceLocation aLoc = a.first->getLocStart();
+ SourceLocation bLoc = b.first->getLocStart();
+ return aLoc.getRawEncoding() < bLoc.getRawEncoding();
+ }
+};
+
+class UninitValsDiagReporter : public UninitVariablesHandler {
+ Sema &S;
+ typedef llvm::SmallVector<UninitUse, 2> UsesVec;
+ typedef llvm::DenseMap<const VarDecl *, UsesVec*> UsesMap;
+ UsesMap *uses;
+
+public:
+ UninitValsDiagReporter(Sema &S) : S(S), uses(0) {}
+ ~UninitValsDiagReporter() {
+ flushDiagnostics();
+ }
+
+ void handleUseOfUninitVariable(const Expr *ex, const VarDecl *vd,
+ bool isAlwaysUninit) {
+ if (!uses)
+ uses = new UsesMap();
+
+ UsesVec *&vec = (*uses)[vd];
+ if (!vec)
+ vec = new UsesVec();
+
+ vec->push_back(std::make_pair(ex, isAlwaysUninit));
+ }
+
+ void flushDiagnostics() {
+ if (!uses)
+ return;
+
+ for (UsesMap::iterator i = uses->begin(), e = uses->end(); i != e; ++i) {
+ const VarDecl *vd = i->first;
+ UsesVec *vec = i->second;
+
+ bool fixitIssued = false;
+
+ // Sort the uses by their SourceLocations. While not strictly
+ // guaranteed to produce them in line/column order, this will provide
+ // a stable ordering.
+ std::sort(vec->begin(), vec->end(), SLocSort());
+
+ for (UsesVec::iterator vi = vec->begin(), ve = vec->end(); vi != ve;
+ ++vi) {
+ if (!DiagnoseUninitializedUse(S, vd, vi->first,
+ /*isAlwaysUninit=*/vi->second))
+ continue;
+
+ // Suggest a fixit hint the first time we diagnose a use of a variable.
+ if (!fixitIssued) {
+ SuggestInitializationFixit(S, vd);
+ fixitIssued = true;
+ }
+ }
+
+ delete vec;
+ }
+ delete uses;
+ }
+};
+}
+
+//===----------------------------------------------------------------------===//
+// AnalysisBasedWarnings - Worker object used by Sema to execute analysis-based
+// warnings on a function, method, or block.
+//===----------------------------------------------------------------------===//
+
+clang::sema::AnalysisBasedWarnings::Policy::Policy() {
+ enableCheckFallThrough = 1;
+ enableCheckUnreachable = 0;
+}
+
+clang::sema::AnalysisBasedWarnings::AnalysisBasedWarnings(Sema &s) : S(s) {
+ Diagnostic &D = S.getDiagnostics();
+ DefaultPolicy.enableCheckUnreachable = (unsigned)
+ (D.getDiagnosticLevel(diag::warn_unreachable, SourceLocation()) !=
+ Diagnostic::Ignored);
+}
+
+static void flushDiagnostics(Sema &S, sema::FunctionScopeInfo *fscope) {
+ for (llvm::SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
+ i = fscope->PossiblyUnreachableDiags.begin(),
+ e = fscope->PossiblyUnreachableDiags.end();
+ i != e; ++i) {
+ const sema::PossiblyUnreachableDiag &D = *i;
+ S.Diag(D.Loc, D.PD);
+ }
+}
+
+void clang::sema::
+AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
+ sema::FunctionScopeInfo *fscope,
+ const Decl *D, const BlockExpr *blkExpr) {
+
+ // We avoid doing analysis-based warnings when there are errors for
+ // two reasons:
+ // (1) The CFGs often can't be constructed (if the body is invalid), so
+ // don't bother trying.
+ // (2) The code already has problems; running the analysis just takes more
+ // time.
+ Diagnostic &Diags = S.getDiagnostics();
+
+ // Do not do any analysis for declarations in system headers if we are
+ // going to just ignore them.
+ if (Diags.getSuppressSystemWarnings() &&
+ S.SourceMgr.isInSystemHeader(D->getLocation()))
+ return;
+
+ // For code in dependent contexts, we'll do this at instantiation time.
+ if (cast<DeclContext>(D)->isDependentContext())
+ return;
+
+ if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred()) {
+ // Flush out any possibly unreachable diagnostics.
+ flushDiagnostics(S, fscope);
+ return;
+ }
+
+ const Stmt *Body = D->getBody();
+ assert(Body);
+
+ // Don't generate EH edges for CallExprs as we'd like to avoid the n^2
+ // explosion for destrutors that can result and the compile time hit.
+ AnalysisContext AC(D, 0, /*useUnoptimizedCFG=*/false, /*addehedges=*/false,
+ /*addImplicitDtors=*/true, /*addInitializers=*/true);
+
+ // Emit delayed diagnostics.
+ if (!fscope->PossiblyUnreachableDiags.empty()) {
+ bool analyzed = false;
+
+ // Register the expressions with the CFGBuilder.
+ for (llvm::SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
+ i = fscope->PossiblyUnreachableDiags.begin(),
+ e = fscope->PossiblyUnreachableDiags.end();
+ i != e; ++i) {
+ if (const Stmt *stmt = i->stmt)
+ AC.registerForcedBlockExpression(stmt);
+ }
+
+ if (AC.getCFG()) {
+ analyzed = true;
+ for (llvm::SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
+ i = fscope->PossiblyUnreachableDiags.begin(),
+ e = fscope->PossiblyUnreachableDiags.end();
+ i != e; ++i)
+ {
+ const sema::PossiblyUnreachableDiag &D = *i;
+ bool processed = false;
+ if (const Stmt *stmt = i->stmt) {
+ const CFGBlock *block = AC.getBlockForRegisteredExpression(stmt);
+ assert(block);
+ if (CFGReverseBlockReachabilityAnalysis *cra = AC.getCFGReachablityAnalysis()) {
+ // Can this block be reached from the entrance?
+ if (cra->isReachable(&AC.getCFG()->getEntry(), block))
+ S.Diag(D.Loc, D.PD);
+ processed = true;
+ }
+ }
+ if (!processed) {
+ // Emit the warning anyway if we cannot map to a basic block.
+ S.Diag(D.Loc, D.PD);
+ }
+ }
+ }
+
+ if (!analyzed)
+ flushDiagnostics(S, fscope);
+ }
+
+
+ // Warning: check missing 'return'
+ if (P.enableCheckFallThrough) {
+ const CheckFallThroughDiagnostics &CD =
+ (isa<BlockDecl>(D) ? CheckFallThroughDiagnostics::MakeForBlock()
+ : CheckFallThroughDiagnostics::MakeForFunction(D));
+ CheckFallThroughForBody(S, D, Body, blkExpr, CD, AC);
+ }
+
+ // Warning: check for unreachable code
+ if (P.enableCheckUnreachable)
+ CheckUnreachable(S, AC);
+
+ if (Diags.getDiagnosticLevel(diag::warn_uninit_var, D->getLocStart())
+ != Diagnostic::Ignored ||
+ Diags.getDiagnosticLevel(diag::warn_maybe_uninit_var, D->getLocStart())
+ != Diagnostic::Ignored) {
+ if (CFG *cfg = AC.getCFG()) {
+ UninitValsDiagReporter reporter(S);
+ runUninitializedVariablesAnalysis(*cast<DeclContext>(D), *cfg, AC,
+ reporter);
+ }
+ }
+}
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