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2347 lines
83 KiB
2347 lines
83 KiB
//=- AnalysisBasedWarnings.cpp - Sema warnings based on libAnalysis -*- C++ -*-=//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines analysis_warnings::[Policy,Executor].
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// Together they are used by Sema to issue warnings based on inexpensive
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// static analysis algorithms in libAnalysis.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Sema/AnalysisBasedWarnings.h"
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#include "clang/AST/DeclCXX.h"
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#include "clang/AST/DeclObjC.h"
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#include "clang/AST/EvaluatedExprVisitor.h"
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#include "clang/AST/ExprCXX.h"
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#include "clang/AST/ExprObjC.h"
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#include "clang/AST/ParentMap.h"
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#include "clang/AST/RecursiveASTVisitor.h"
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#include "clang/AST/StmtCXX.h"
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#include "clang/AST/StmtObjC.h"
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#include "clang/AST/StmtVisitor.h"
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#include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
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#include "clang/Analysis/Analyses/Consumed.h"
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#include "clang/Analysis/Analyses/ReachableCode.h"
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#include "clang/Analysis/Analyses/ThreadSafety.h"
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#include "clang/Analysis/Analyses/UninitializedValues.h"
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#include "clang/Analysis/AnalysisDeclContext.h"
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#include "clang/Analysis/CFG.h"
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#include "clang/Analysis/CFGStmtMap.h"
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#include "clang/Basic/SourceLocation.h"
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#include "clang/Basic/SourceManager.h"
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#include "clang/Lex/Preprocessor.h"
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#include "clang/Sema/ScopeInfo.h"
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#include "clang/Sema/SemaInternal.h"
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#include "llvm/ADT/BitVector.h"
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#include "llvm/ADT/MapVector.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/Support/Casting.h"
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#include <algorithm>
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#include <deque>
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#include <iterator>
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using namespace clang;
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//===----------------------------------------------------------------------===//
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// Unreachable code analysis.
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//===----------------------------------------------------------------------===//
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namespace {
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class UnreachableCodeHandler : public reachable_code::Callback {
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Sema &S;
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SourceRange PreviousSilenceableCondVal;
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public:
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UnreachableCodeHandler(Sema &s) : S(s) {}
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void HandleUnreachable(reachable_code::UnreachableKind UK,
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SourceLocation L,
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SourceRange SilenceableCondVal,
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SourceRange R1,
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SourceRange R2) override {
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// Avoid reporting multiple unreachable code diagnostics that are
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// triggered by the same conditional value.
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if (PreviousSilenceableCondVal.isValid() &&
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SilenceableCondVal.isValid() &&
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PreviousSilenceableCondVal == SilenceableCondVal)
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return;
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PreviousSilenceableCondVal = SilenceableCondVal;
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unsigned diag = diag::warn_unreachable;
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switch (UK) {
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case reachable_code::UK_Break:
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diag = diag::warn_unreachable_break;
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break;
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case reachable_code::UK_Return:
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diag = diag::warn_unreachable_return;
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break;
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case reachable_code::UK_Loop_Increment:
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diag = diag::warn_unreachable_loop_increment;
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break;
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case reachable_code::UK_Other:
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break;
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}
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S.Diag(L, diag) << R1 << R2;
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SourceLocation Open = SilenceableCondVal.getBegin();
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if (Open.isValid()) {
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SourceLocation Close = SilenceableCondVal.getEnd();
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Close = S.getLocForEndOfToken(Close);
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if (Close.isValid()) {
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S.Diag(Open, diag::note_unreachable_silence)
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<< FixItHint::CreateInsertion(Open, "/* DISABLES CODE */ (")
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<< FixItHint::CreateInsertion(Close, ")");
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}
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}
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}
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};
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} // anonymous namespace
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/// CheckUnreachable - Check for unreachable code.
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static void CheckUnreachable(Sema &S, AnalysisDeclContext &AC) {
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// As a heuristic prune all diagnostics not in the main file. Currently
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// the majority of warnings in headers are false positives. These
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// are largely caused by configuration state, e.g. preprocessor
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// defined code, etc.
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//
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// Note that this is also a performance optimization. Analyzing
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// headers many times can be expensive.
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if (!S.getSourceManager().isInMainFile(AC.getDecl()->getBeginLoc()))
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return;
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UnreachableCodeHandler UC(S);
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reachable_code::FindUnreachableCode(AC, S.getPreprocessor(), UC);
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}
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namespace {
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/// Warn on logical operator errors in CFGBuilder
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class LogicalErrorHandler : public CFGCallback {
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Sema &S;
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public:
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LogicalErrorHandler(Sema &S) : CFGCallback(), S(S) {}
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static bool HasMacroID(const Expr *E) {
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if (E->getExprLoc().isMacroID())
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return true;
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// Recurse to children.
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for (const Stmt *SubStmt : E->children())
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if (const Expr *SubExpr = dyn_cast_or_null<Expr>(SubStmt))
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if (HasMacroID(SubExpr))
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return true;
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return false;
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}
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void compareAlwaysTrue(const BinaryOperator *B, bool isAlwaysTrue) override {
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if (HasMacroID(B))
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return;
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SourceRange DiagRange = B->getSourceRange();
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S.Diag(B->getExprLoc(), diag::warn_tautological_overlap_comparison)
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<< DiagRange << isAlwaysTrue;
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}
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void compareBitwiseEquality(const BinaryOperator *B,
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bool isAlwaysTrue) override {
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if (HasMacroID(B))
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return;
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SourceRange DiagRange = B->getSourceRange();
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S.Diag(B->getExprLoc(), diag::warn_comparison_bitwise_always)
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<< DiagRange << isAlwaysTrue;
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}
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void compareBitwiseOr(const BinaryOperator *B) override {
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if (HasMacroID(B))
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return;
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SourceRange DiagRange = B->getSourceRange();
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S.Diag(B->getExprLoc(), diag::warn_comparison_bitwise_or) << DiagRange;
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}
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static bool hasActiveDiagnostics(DiagnosticsEngine &Diags,
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SourceLocation Loc) {
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return !Diags.isIgnored(diag::warn_tautological_overlap_comparison, Loc) ||
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!Diags.isIgnored(diag::warn_comparison_bitwise_or, Loc);
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}
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};
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} // anonymous namespace
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//===----------------------------------------------------------------------===//
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// Check for infinite self-recursion in functions
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//===----------------------------------------------------------------------===//
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// Returns true if the function is called anywhere within the CFGBlock.
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// For member functions, the additional condition of being call from the
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// this pointer is required.
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static bool hasRecursiveCallInPath(const FunctionDecl *FD, CFGBlock &Block) {
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// Process all the Stmt's in this block to find any calls to FD.
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for (const auto &B : Block) {
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if (B.getKind() != CFGElement::Statement)
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continue;
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const CallExpr *CE = dyn_cast<CallExpr>(B.getAs<CFGStmt>()->getStmt());
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if (!CE || !CE->getCalleeDecl() ||
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CE->getCalleeDecl()->getCanonicalDecl() != FD)
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continue;
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// Skip function calls which are qualified with a templated class.
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if (const DeclRefExpr *DRE =
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dyn_cast<DeclRefExpr>(CE->getCallee()->IgnoreParenImpCasts())) {
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if (NestedNameSpecifier *NNS = DRE->getQualifier()) {
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if (NNS->getKind() == NestedNameSpecifier::TypeSpec &&
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isa<TemplateSpecializationType>(NNS->getAsType())) {
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continue;
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}
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}
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}
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const CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(CE);
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if (!MCE || isa<CXXThisExpr>(MCE->getImplicitObjectArgument()) ||
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!MCE->getMethodDecl()->isVirtual())
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return true;
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}
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return false;
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}
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// Returns true if every path from the entry block passes through a call to FD.
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static bool checkForRecursiveFunctionCall(const FunctionDecl *FD, CFG *cfg) {
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llvm::SmallPtrSet<CFGBlock *, 16> Visited;
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llvm::SmallVector<CFGBlock *, 16> WorkList;
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// Keep track of whether we found at least one recursive path.
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bool foundRecursion = false;
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const unsigned ExitID = cfg->getExit().getBlockID();
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// Seed the work list with the entry block.
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WorkList.push_back(&cfg->getEntry());
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while (!WorkList.empty()) {
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CFGBlock *Block = WorkList.pop_back_val();
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for (auto I = Block->succ_begin(), E = Block->succ_end(); I != E; ++I) {
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if (CFGBlock *SuccBlock = *I) {
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if (!Visited.insert(SuccBlock).second)
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continue;
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// Found a path to the exit node without a recursive call.
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if (ExitID == SuccBlock->getBlockID())
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return false;
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// If the successor block contains a recursive call, end analysis there.
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if (hasRecursiveCallInPath(FD, *SuccBlock)) {
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foundRecursion = true;
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continue;
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}
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WorkList.push_back(SuccBlock);
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}
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}
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}
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return foundRecursion;
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}
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static void checkRecursiveFunction(Sema &S, const FunctionDecl *FD,
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const Stmt *Body, AnalysisDeclContext &AC) {
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FD = FD->getCanonicalDecl();
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// Only run on non-templated functions and non-templated members of
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// templated classes.
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if (FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate &&
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FD->getTemplatedKind() != FunctionDecl::TK_MemberSpecialization)
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return;
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CFG *cfg = AC.getCFG();
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if (!cfg) return;
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// If the exit block is unreachable, skip processing the function.
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if (cfg->getExit().pred_empty())
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return;
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// Emit diagnostic if a recursive function call is detected for all paths.
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if (checkForRecursiveFunctionCall(FD, cfg))
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S.Diag(Body->getBeginLoc(), diag::warn_infinite_recursive_function);
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}
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//===----------------------------------------------------------------------===//
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// Check for throw in a non-throwing function.
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//===----------------------------------------------------------------------===//
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/// Determine whether an exception thrown by E, unwinding from ThrowBlock,
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/// can reach ExitBlock.
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static bool throwEscapes(Sema &S, const CXXThrowExpr *E, CFGBlock &ThrowBlock,
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CFG *Body) {
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SmallVector<CFGBlock *, 16> Stack;
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llvm::BitVector Queued(Body->getNumBlockIDs());
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Stack.push_back(&ThrowBlock);
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Queued[ThrowBlock.getBlockID()] = true;
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while (!Stack.empty()) {
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CFGBlock &UnwindBlock = *Stack.back();
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Stack.pop_back();
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for (auto &Succ : UnwindBlock.succs()) {
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if (!Succ.isReachable() || Queued[Succ->getBlockID()])
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continue;
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if (Succ->getBlockID() == Body->getExit().getBlockID())
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return true;
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if (auto *Catch =
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dyn_cast_or_null<CXXCatchStmt>(Succ->getLabel())) {
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QualType Caught = Catch->getCaughtType();
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if (Caught.isNull() || // catch (...) catches everything
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!E->getSubExpr() || // throw; is considered cuaght by any handler
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S.handlerCanCatch(Caught, E->getSubExpr()->getType()))
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// Exception doesn't escape via this path.
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break;
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} else {
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Stack.push_back(Succ);
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Queued[Succ->getBlockID()] = true;
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}
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}
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}
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return false;
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}
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static void visitReachableThrows(
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CFG *BodyCFG,
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llvm::function_ref<void(const CXXThrowExpr *, CFGBlock &)> Visit) {
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llvm::BitVector Reachable(BodyCFG->getNumBlockIDs());
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clang::reachable_code::ScanReachableFromBlock(&BodyCFG->getEntry(), Reachable);
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for (CFGBlock *B : *BodyCFG) {
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if (!Reachable[B->getBlockID()])
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continue;
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for (CFGElement &E : *B) {
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Optional<CFGStmt> S = E.getAs<CFGStmt>();
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if (!S)
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continue;
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if (auto *Throw = dyn_cast<CXXThrowExpr>(S->getStmt()))
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Visit(Throw, *B);
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}
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}
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}
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static void EmitDiagForCXXThrowInNonThrowingFunc(Sema &S, SourceLocation OpLoc,
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const FunctionDecl *FD) {
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if (!S.getSourceManager().isInSystemHeader(OpLoc) &&
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FD->getTypeSourceInfo()) {
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S.Diag(OpLoc, diag::warn_throw_in_noexcept_func) << FD;
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if (S.getLangOpts().CPlusPlus11 &&
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(isa<CXXDestructorDecl>(FD) ||
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FD->getDeclName().getCXXOverloadedOperator() == OO_Delete ||
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FD->getDeclName().getCXXOverloadedOperator() == OO_Array_Delete)) {
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if (const auto *Ty = FD->getTypeSourceInfo()->getType()->
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getAs<FunctionProtoType>())
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S.Diag(FD->getLocation(), diag::note_throw_in_dtor)
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<< !isa<CXXDestructorDecl>(FD) << !Ty->hasExceptionSpec()
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<< FD->getExceptionSpecSourceRange();
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} else
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S.Diag(FD->getLocation(), diag::note_throw_in_function)
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<< FD->getExceptionSpecSourceRange();
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}
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}
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static void checkThrowInNonThrowingFunc(Sema &S, const FunctionDecl *FD,
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AnalysisDeclContext &AC) {
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CFG *BodyCFG = AC.getCFG();
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if (!BodyCFG)
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return;
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if (BodyCFG->getExit().pred_empty())
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return;
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visitReachableThrows(BodyCFG, [&](const CXXThrowExpr *Throw, CFGBlock &Block) {
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if (throwEscapes(S, Throw, Block, BodyCFG))
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EmitDiagForCXXThrowInNonThrowingFunc(S, Throw->getThrowLoc(), FD);
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});
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}
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static bool isNoexcept(const FunctionDecl *FD) {
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const auto *FPT = FD->getType()->castAs<FunctionProtoType>();
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if (FPT->isNothrow() || FD->hasAttr<NoThrowAttr>())
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return true;
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return false;
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}
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|
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//===----------------------------------------------------------------------===//
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// Check for missing return value.
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//===----------------------------------------------------------------------===//
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enum ControlFlowKind {
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UnknownFallThrough,
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NeverFallThrough,
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MaybeFallThrough,
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AlwaysFallThrough,
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NeverFallThroughOrReturn
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};
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|
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/// CheckFallThrough - Check that we don't fall off the end of a
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/// Statement that should return a value.
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///
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/// \returns AlwaysFallThrough iff we always fall off the end of the statement,
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/// MaybeFallThrough iff we might or might not fall off the end,
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/// NeverFallThroughOrReturn iff we never fall off the end of the statement or
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/// return. We assume NeverFallThrough iff we never fall off the end of the
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/// statement but we may return. We assume that functions not marked noreturn
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/// will return.
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static ControlFlowKind CheckFallThrough(AnalysisDeclContext &AC) {
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CFG *cfg = AC.getCFG();
|
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if (!cfg) 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(),
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|
live);
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|
|
|
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 (const auto *B : *cfg) {
|
|
if (!live[B->getBlockID()]) {
|
|
if (B->pred_begin() == B->pred_end()) {
|
|
const Stmt *Term = B->getTerminatorStmt();
|
|
if (Term && isa<CXXTryStmt>(Term))
|
|
// When not adding EH edges from calls, catch clauses
|
|
// can otherwise seem dead. Avoid noting them as dead.
|
|
count += reachable_code::ScanReachableFromBlock(B, live);
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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 =
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cfg->getExit().filtered_pred_start_end(FO);
|
|
I.hasMore(); ++I) {
|
|
const CFGBlock &B = **I;
|
|
if (!live[B.getBlockID()])
|
|
continue;
|
|
|
|
// Skip blocks which contain an element marked as no-return. They don't
|
|
// represent actually viable edges into the exit block, so mark them as
|
|
// abnormal.
|
|
if (B.hasNoReturnElement()) {
|
|
HasAbnormalEdge = true;
|
|
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).
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|
CFGBlock::const_reverse_iterator ri = B.rbegin(), re = B.rend();
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|
|
for ( ; ri != re ; ++ri)
|
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if (ri->getAs<CFGStmt>())
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break;
|
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|
|
// No more CFGElements in the block?
|
|
if (ri == re) {
|
|
const Stmt *Term = B.getTerminatorStmt();
|
|
if (Term && isa<CXXTryStmt>(Term)) {
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|
HasAbnormalEdge = true;
|
|
continue;
|
|
}
|
|
// A labeled empty statement, or the entry block...
|
|
HasPlainEdge = true;
|
|
continue;
|
|
}
|
|
|
|
CFGStmt CS = ri->castAs<CFGStmt>();
|
|
const Stmt *S = CS.getStmt();
|
|
if (isa<ReturnStmt>(S) || isa<CoreturnStmt>(S)) {
|
|
HasLiveReturn = true;
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|
continue;
|
|
}
|
|
if (isa<ObjCAtThrowStmt>(S)) {
|
|
HasFakeEdge = true;
|
|
continue;
|
|
}
|
|
if (isa<CXXThrowExpr>(S)) {
|
|
HasFakeEdge = true;
|
|
continue;
|
|
}
|
|
if (isa<MSAsmStmt>(S)) {
|
|
// TODO: Verify this is correct.
|
|
HasFakeEdge = true;
|
|
HasLiveReturn = true;
|
|
continue;
|
|
}
|
|
if (isa<CXXTryStmt>(S)) {
|
|
HasAbnormalEdge = true;
|
|
continue;
|
|
}
|
|
if (std::find(B.succ_begin(), B.succ_end(), &cfg->getExit())
|
|
== B.succ_end()) {
|
|
HasAbnormalEdge = true;
|
|
continue;
|
|
}
|
|
|
|
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;
|
|
enum { Function, Block, Lambda, Coroutine } 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();
|
|
|
|
// Don't suggest that template instantiations be marked "noreturn"
|
|
bool isTemplateInstantiation = false;
|
|
if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(Func))
|
|
isTemplateInstantiation = Function->isTemplateInstantiation();
|
|
|
|
if (!isVirtualMethod && !isTemplateInstantiation)
|
|
D.diag_NeverFallThroughOrReturn =
|
|
diag::warn_suggest_noreturn_function;
|
|
else
|
|
D.diag_NeverFallThroughOrReturn = 0;
|
|
|
|
D.funMode = Function;
|
|
return D;
|
|
}
|
|
|
|
static CheckFallThroughDiagnostics MakeForCoroutine(const Decl *Func) {
|
|
CheckFallThroughDiagnostics D;
|
|
D.FuncLoc = Func->getLocation();
|
|
D.diag_MaybeFallThrough_HasNoReturn = 0;
|
|
D.diag_MaybeFallThrough_ReturnsNonVoid =
|
|
diag::warn_maybe_falloff_nonvoid_coroutine;
|
|
D.diag_AlwaysFallThrough_HasNoReturn = 0;
|
|
D.diag_AlwaysFallThrough_ReturnsNonVoid =
|
|
diag::warn_falloff_nonvoid_coroutine;
|
|
D.funMode = Coroutine;
|
|
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 = 0;
|
|
D.funMode = Block;
|
|
return D;
|
|
}
|
|
|
|
static CheckFallThroughDiagnostics MakeForLambda() {
|
|
CheckFallThroughDiagnostics D;
|
|
D.diag_MaybeFallThrough_HasNoReturn =
|
|
diag::err_noreturn_lambda_has_return_expr;
|
|
D.diag_MaybeFallThrough_ReturnsNonVoid =
|
|
diag::warn_maybe_falloff_nonvoid_lambda;
|
|
D.diag_AlwaysFallThrough_HasNoReturn =
|
|
diag::err_noreturn_lambda_has_return_expr;
|
|
D.diag_AlwaysFallThrough_ReturnsNonVoid =
|
|
diag::warn_falloff_nonvoid_lambda;
|
|
D.diag_NeverFallThroughOrReturn = 0;
|
|
D.funMode = Lambda;
|
|
return D;
|
|
}
|
|
|
|
bool checkDiagnostics(DiagnosticsEngine &D, bool ReturnsVoid,
|
|
bool HasNoReturn) const {
|
|
if (funMode == Function) {
|
|
return (ReturnsVoid ||
|
|
D.isIgnored(diag::warn_maybe_falloff_nonvoid_function,
|
|
FuncLoc)) &&
|
|
(!HasNoReturn ||
|
|
D.isIgnored(diag::warn_noreturn_function_has_return_expr,
|
|
FuncLoc)) &&
|
|
(!ReturnsVoid ||
|
|
D.isIgnored(diag::warn_suggest_noreturn_block, FuncLoc));
|
|
}
|
|
if (funMode == Coroutine) {
|
|
return (ReturnsVoid ||
|
|
D.isIgnored(diag::warn_maybe_falloff_nonvoid_function, FuncLoc) ||
|
|
D.isIgnored(diag::warn_maybe_falloff_nonvoid_coroutine,
|
|
FuncLoc)) &&
|
|
(!HasNoReturn);
|
|
}
|
|
// For blocks / lambdas.
|
|
return ReturnsVoid && !HasNoReturn;
|
|
}
|
|
};
|
|
|
|
} // anonymous namespace
|
|
|
|
/// CheckFallThroughForBody - 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,
|
|
QualType BlockType,
|
|
const CheckFallThroughDiagnostics &CD,
|
|
AnalysisDeclContext &AC,
|
|
sema::FunctionScopeInfo *FSI) {
|
|
|
|
bool ReturnsVoid = false;
|
|
bool HasNoReturn = false;
|
|
bool IsCoroutine = FSI->isCoroutine();
|
|
|
|
if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
|
|
if (const auto *CBody = dyn_cast<CoroutineBodyStmt>(Body))
|
|
ReturnsVoid = CBody->getFallthroughHandler() != nullptr;
|
|
else
|
|
ReturnsVoid = FD->getReturnType()->isVoidType();
|
|
HasNoReturn = FD->isNoReturn();
|
|
}
|
|
else if (const auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
|
|
ReturnsVoid = MD->getReturnType()->isVoidType();
|
|
HasNoReturn = MD->hasAttr<NoReturnAttr>();
|
|
}
|
|
else if (isa<BlockDecl>(D)) {
|
|
if (const FunctionType *FT =
|
|
BlockType->getPointeeType()->getAs<FunctionType>()) {
|
|
if (FT->getReturnType()->isVoidType())
|
|
ReturnsVoid = true;
|
|
if (FT->getNoReturnAttr())
|
|
HasNoReturn = true;
|
|
}
|
|
}
|
|
|
|
DiagnosticsEngine &Diags = S.getDiagnostics();
|
|
|
|
// Short circuit for compilation speed.
|
|
if (CD.checkDiagnostics(Diags, ReturnsVoid, HasNoReturn))
|
|
return;
|
|
SourceLocation LBrace = Body->getBeginLoc(), RBrace = Body->getEndLoc();
|
|
auto EmitDiag = [&](SourceLocation Loc, unsigned DiagID) {
|
|
if (IsCoroutine)
|
|
S.Diag(Loc, DiagID) << FSI->CoroutinePromise->getType();
|
|
else
|
|
S.Diag(Loc, DiagID);
|
|
};
|
|
|
|
// cpu_dispatch functions permit empty function bodies for ICC compatibility.
|
|
if (D->getAsFunction() && D->getAsFunction()->isCPUDispatchMultiVersion())
|
|
return;
|
|
|
|
// Either in a function body compound statement, or a function-try-block.
|
|
switch (CheckFallThrough(AC)) {
|
|
case UnknownFallThrough:
|
|
break;
|
|
|
|
case MaybeFallThrough:
|
|
if (HasNoReturn)
|
|
EmitDiag(RBrace, CD.diag_MaybeFallThrough_HasNoReturn);
|
|
else if (!ReturnsVoid)
|
|
EmitDiag(RBrace, CD.diag_MaybeFallThrough_ReturnsNonVoid);
|
|
break;
|
|
case AlwaysFallThrough:
|
|
if (HasNoReturn)
|
|
EmitDiag(RBrace, CD.diag_AlwaysFallThrough_HasNoReturn);
|
|
else if (!ReturnsVoid)
|
|
EmitDiag(RBrace, CD.diag_AlwaysFallThrough_ReturnsNonVoid);
|
|
break;
|
|
case NeverFallThroughOrReturn:
|
|
if (ReturnsVoid && !HasNoReturn && CD.diag_NeverFallThroughOrReturn) {
|
|
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
|
|
S.Diag(LBrace, CD.diag_NeverFallThroughOrReturn) << 0 << FD;
|
|
} else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
|
|
S.Diag(LBrace, CD.diag_NeverFallThroughOrReturn) << 1 << MD;
|
|
} else {
|
|
S.Diag(LBrace, 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 ConstEvaluatedExprVisitor<ContainsReference> {
|
|
bool FoundReference;
|
|
const DeclRefExpr *Needle;
|
|
|
|
public:
|
|
typedef ConstEvaluatedExprVisitor<ContainsReference> Inherited;
|
|
|
|
ContainsReference(ASTContext &Context, const DeclRefExpr *Needle)
|
|
: Inherited(Context), FoundReference(false), Needle(Needle) {}
|
|
|
|
void VisitExpr(const Expr *E) {
|
|
// Stop evaluating if we already have a reference.
|
|
if (FoundReference)
|
|
return;
|
|
|
|
Inherited::VisitExpr(E);
|
|
}
|
|
|
|
void VisitDeclRefExpr(const DeclRefExpr *E) {
|
|
if (E == Needle)
|
|
FoundReference = true;
|
|
else
|
|
Inherited::VisitDeclRefExpr(E);
|
|
}
|
|
|
|
bool doesContainReference() const { return FoundReference; }
|
|
};
|
|
} // anonymous namespace
|
|
|
|
static bool SuggestInitializationFixit(Sema &S, const VarDecl *VD) {
|
|
QualType VariableTy = VD->getType().getCanonicalType();
|
|
if (VariableTy->isBlockPointerType() &&
|
|
!VD->hasAttr<BlocksAttr>()) {
|
|
S.Diag(VD->getLocation(), diag::note_block_var_fixit_add_initialization)
|
|
<< VD->getDeclName()
|
|
<< FixItHint::CreateInsertion(VD->getLocation(), "__block ");
|
|
return true;
|
|
}
|
|
|
|
// Don't issue a fixit if there is already an initializer.
|
|
if (VD->getInit())
|
|
return false;
|
|
|
|
// Don't suggest a fixit inside macros.
|
|
if (VD->getEndLoc().isMacroID())
|
|
return false;
|
|
|
|
SourceLocation Loc = S.getLocForEndOfToken(VD->getEndLoc());
|
|
|
|
// Suggest possible initialization (if any).
|
|
std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
|
|
if (Init.empty())
|
|
return false;
|
|
|
|
S.Diag(Loc, diag::note_var_fixit_add_initialization) << VD->getDeclName()
|
|
<< FixItHint::CreateInsertion(Loc, Init);
|
|
return true;
|
|
}
|
|
|
|
/// Create a fixit to remove an if-like statement, on the assumption that its
|
|
/// condition is CondVal.
|
|
static void CreateIfFixit(Sema &S, const Stmt *If, const Stmt *Then,
|
|
const Stmt *Else, bool CondVal,
|
|
FixItHint &Fixit1, FixItHint &Fixit2) {
|
|
if (CondVal) {
|
|
// If condition is always true, remove all but the 'then'.
|
|
Fixit1 = FixItHint::CreateRemoval(
|
|
CharSourceRange::getCharRange(If->getBeginLoc(), Then->getBeginLoc()));
|
|
if (Else) {
|
|
SourceLocation ElseKwLoc = S.getLocForEndOfToken(Then->getEndLoc());
|
|
Fixit2 =
|
|
FixItHint::CreateRemoval(SourceRange(ElseKwLoc, Else->getEndLoc()));
|
|
}
|
|
} else {
|
|
// If condition is always false, remove all but the 'else'.
|
|
if (Else)
|
|
Fixit1 = FixItHint::CreateRemoval(CharSourceRange::getCharRange(
|
|
If->getBeginLoc(), Else->getBeginLoc()));
|
|
else
|
|
Fixit1 = FixItHint::CreateRemoval(If->getSourceRange());
|
|
}
|
|
}
|
|
|
|
/// DiagUninitUse -- Helper function to produce a diagnostic for an
|
|
/// uninitialized use of a variable.
|
|
static void DiagUninitUse(Sema &S, const VarDecl *VD, const UninitUse &Use,
|
|
bool IsCapturedByBlock) {
|
|
bool Diagnosed = false;
|
|
|
|
switch (Use.getKind()) {
|
|
case UninitUse::Always:
|
|
S.Diag(Use.getUser()->getBeginLoc(), diag::warn_uninit_var)
|
|
<< VD->getDeclName() << IsCapturedByBlock
|
|
<< Use.getUser()->getSourceRange();
|
|
return;
|
|
|
|
case UninitUse::AfterDecl:
|
|
case UninitUse::AfterCall:
|
|
S.Diag(VD->getLocation(), diag::warn_sometimes_uninit_var)
|
|
<< VD->getDeclName() << IsCapturedByBlock
|
|
<< (Use.getKind() == UninitUse::AfterDecl ? 4 : 5)
|
|
<< const_cast<DeclContext*>(VD->getLexicalDeclContext())
|
|
<< VD->getSourceRange();
|
|
S.Diag(Use.getUser()->getBeginLoc(), diag::note_uninit_var_use)
|
|
<< IsCapturedByBlock << Use.getUser()->getSourceRange();
|
|
return;
|
|
|
|
case UninitUse::Maybe:
|
|
case UninitUse::Sometimes:
|
|
// Carry on to report sometimes-uninitialized branches, if possible,
|
|
// or a 'may be used uninitialized' diagnostic otherwise.
|
|
break;
|
|
}
|
|
|
|
// Diagnose each branch which leads to a sometimes-uninitialized use.
|
|
for (UninitUse::branch_iterator I = Use.branch_begin(), E = Use.branch_end();
|
|
I != E; ++I) {
|
|
assert(Use.getKind() == UninitUse::Sometimes);
|
|
|
|
const Expr *User = Use.getUser();
|
|
const Stmt *Term = I->Terminator;
|
|
|
|
// Information used when building the diagnostic.
|
|
unsigned DiagKind;
|
|
StringRef Str;
|
|
SourceRange Range;
|
|
|
|
// FixIts to suppress the diagnostic by removing the dead condition.
|
|
// For all binary terminators, branch 0 is taken if the condition is true,
|
|
// and branch 1 is taken if the condition is false.
|
|
int RemoveDiagKind = -1;
|
|
const char *FixitStr =
|
|
S.getLangOpts().CPlusPlus ? (I->Output ? "true" : "false")
|
|
: (I->Output ? "1" : "0");
|
|
FixItHint Fixit1, Fixit2;
|
|
|
|
switch (Term ? Term->getStmtClass() : Stmt::DeclStmtClass) {
|
|
default:
|
|
// Don't know how to report this. Just fall back to 'may be used
|
|
// uninitialized'. FIXME: Can this happen?
|
|
continue;
|
|
|
|
// "condition is true / condition is false".
|
|
case Stmt::IfStmtClass: {
|
|
const IfStmt *IS = cast<IfStmt>(Term);
|
|
DiagKind = 0;
|
|
Str = "if";
|
|
Range = IS->getCond()->getSourceRange();
|
|
RemoveDiagKind = 0;
|
|
CreateIfFixit(S, IS, IS->getThen(), IS->getElse(),
|
|
I->Output, Fixit1, Fixit2);
|
|
break;
|
|
}
|
|
case Stmt::ConditionalOperatorClass: {
|
|
const ConditionalOperator *CO = cast<ConditionalOperator>(Term);
|
|
DiagKind = 0;
|
|
Str = "?:";
|
|
Range = CO->getCond()->getSourceRange();
|
|
RemoveDiagKind = 0;
|
|
CreateIfFixit(S, CO, CO->getTrueExpr(), CO->getFalseExpr(),
|
|
I->Output, Fixit1, Fixit2);
|
|
break;
|
|
}
|
|
case Stmt::BinaryOperatorClass: {
|
|
const BinaryOperator *BO = cast<BinaryOperator>(Term);
|
|
if (!BO->isLogicalOp())
|
|
continue;
|
|
DiagKind = 0;
|
|
Str = BO->getOpcodeStr();
|
|
Range = BO->getLHS()->getSourceRange();
|
|
RemoveDiagKind = 0;
|
|
if ((BO->getOpcode() == BO_LAnd && I->Output) ||
|
|
(BO->getOpcode() == BO_LOr && !I->Output))
|
|
// true && y -> y, false || y -> y.
|
|
Fixit1 = FixItHint::CreateRemoval(
|
|
SourceRange(BO->getBeginLoc(), BO->getOperatorLoc()));
|
|
else
|
|
// false && y -> false, true || y -> true.
|
|
Fixit1 = FixItHint::CreateReplacement(BO->getSourceRange(), FixitStr);
|
|
break;
|
|
}
|
|
|
|
// "loop is entered / loop is exited".
|
|
case Stmt::WhileStmtClass:
|
|
DiagKind = 1;
|
|
Str = "while";
|
|
Range = cast<WhileStmt>(Term)->getCond()->getSourceRange();
|
|
RemoveDiagKind = 1;
|
|
Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
|
|
break;
|
|
case Stmt::ForStmtClass:
|
|
DiagKind = 1;
|
|
Str = "for";
|
|
Range = cast<ForStmt>(Term)->getCond()->getSourceRange();
|
|
RemoveDiagKind = 1;
|
|
if (I->Output)
|
|
Fixit1 = FixItHint::CreateRemoval(Range);
|
|
else
|
|
Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
|
|
break;
|
|
case Stmt::CXXForRangeStmtClass:
|
|
if (I->Output == 1) {
|
|
// The use occurs if a range-based for loop's body never executes.
|
|
// That may be impossible, and there's no syntactic fix for this,
|
|
// so treat it as a 'may be uninitialized' case.
|
|
continue;
|
|
}
|
|
DiagKind = 1;
|
|
Str = "for";
|
|
Range = cast<CXXForRangeStmt>(Term)->getRangeInit()->getSourceRange();
|
|
break;
|
|
|
|
// "condition is true / loop is exited".
|
|
case Stmt::DoStmtClass:
|
|
DiagKind = 2;
|
|
Str = "do";
|
|
Range = cast<DoStmt>(Term)->getCond()->getSourceRange();
|
|
RemoveDiagKind = 1;
|
|
Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
|
|
break;
|
|
|
|
// "switch case is taken".
|
|
case Stmt::CaseStmtClass:
|
|
DiagKind = 3;
|
|
Str = "case";
|
|
Range = cast<CaseStmt>(Term)->getLHS()->getSourceRange();
|
|
break;
|
|
case Stmt::DefaultStmtClass:
|
|
DiagKind = 3;
|
|
Str = "default";
|
|
Range = cast<DefaultStmt>(Term)->getDefaultLoc();
|
|
break;
|
|
}
|
|
|
|
S.Diag(Range.getBegin(), diag::warn_sometimes_uninit_var)
|
|
<< VD->getDeclName() << IsCapturedByBlock << DiagKind
|
|
<< Str << I->Output << Range;
|
|
S.Diag(User->getBeginLoc(), diag::note_uninit_var_use)
|
|
<< IsCapturedByBlock << User->getSourceRange();
|
|
if (RemoveDiagKind != -1)
|
|
S.Diag(Fixit1.RemoveRange.getBegin(), diag::note_uninit_fixit_remove_cond)
|
|
<< RemoveDiagKind << Str << I->Output << Fixit1 << Fixit2;
|
|
|
|
Diagnosed = true;
|
|
}
|
|
|
|
if (!Diagnosed)
|
|
S.Diag(Use.getUser()->getBeginLoc(), diag::warn_maybe_uninit_var)
|
|
<< VD->getDeclName() << IsCapturedByBlock
|
|
<< Use.getUser()->getSourceRange();
|
|
}
|
|
|
|
/// Diagnose uninitialized const reference usages.
|
|
static bool DiagnoseUninitializedConstRefUse(Sema &S, const VarDecl *VD,
|
|
const UninitUse &Use) {
|
|
S.Diag(Use.getUser()->getBeginLoc(), diag::warn_uninit_const_reference)
|
|
<< VD->getDeclName() << Use.getUser()->getSourceRange();
|
|
return true;
|
|
}
|
|
|
|
/// 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 particular use is one we omit warnings for, returns
|
|
/// false.
|
|
static bool DiagnoseUninitializedUse(Sema &S, const VarDecl *VD,
|
|
const UninitUse &Use,
|
|
bool alwaysReportSelfInit = false) {
|
|
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Use.getUser())) {
|
|
// 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.
|
|
if (const Expr *Initializer = VD->getInit()) {
|
|
if (!alwaysReportSelfInit && DRE == Initializer->IgnoreParenImpCasts())
|
|
return false;
|
|
|
|
ContainsReference CR(S.Context, DRE);
|
|
CR.Visit(Initializer);
|
|
if (CR.doesContainReference()) {
|
|
S.Diag(DRE->getBeginLoc(), diag::warn_uninit_self_reference_in_init)
|
|
<< VD->getDeclName() << VD->getLocation() << DRE->getSourceRange();
|
|
return true;
|
|
}
|
|
}
|
|
|
|
DiagUninitUse(S, VD, Use, false);
|
|
} else {
|
|
const BlockExpr *BE = cast<BlockExpr>(Use.getUser());
|
|
if (VD->getType()->isBlockPointerType() && !VD->hasAttr<BlocksAttr>())
|
|
S.Diag(BE->getBeginLoc(),
|
|
diag::warn_uninit_byref_blockvar_captured_by_block)
|
|
<< VD->getDeclName()
|
|
<< VD->getType().getQualifiers().hasObjCLifetime();
|
|
else
|
|
DiagUninitUse(S, VD, Use, true);
|
|
}
|
|
|
|
// Report where the variable was declared when the use wasn't within
|
|
// the initializer of that declaration & we didn't already suggest
|
|
// an initialization fixit.
|
|
if (!SuggestInitializationFixit(S, VD))
|
|
S.Diag(VD->getBeginLoc(), diag::note_var_declared_here)
|
|
<< VD->getDeclName();
|
|
|
|
return true;
|
|
}
|
|
|
|
namespace {
|
|
class FallthroughMapper : public RecursiveASTVisitor<FallthroughMapper> {
|
|
public:
|
|
FallthroughMapper(Sema &S)
|
|
: FoundSwitchStatements(false),
|
|
S(S) {
|
|
}
|
|
|
|
bool foundSwitchStatements() const { return FoundSwitchStatements; }
|
|
|
|
void markFallthroughVisited(const AttributedStmt *Stmt) {
|
|
bool Found = FallthroughStmts.erase(Stmt);
|
|
assert(Found);
|
|
(void)Found;
|
|
}
|
|
|
|
typedef llvm::SmallPtrSet<const AttributedStmt*, 8> AttrStmts;
|
|
|
|
const AttrStmts &getFallthroughStmts() const {
|
|
return FallthroughStmts;
|
|
}
|
|
|
|
void fillReachableBlocks(CFG *Cfg) {
|
|
assert(ReachableBlocks.empty() && "ReachableBlocks already filled");
|
|
std::deque<const CFGBlock *> BlockQueue;
|
|
|
|
ReachableBlocks.insert(&Cfg->getEntry());
|
|
BlockQueue.push_back(&Cfg->getEntry());
|
|
// Mark all case blocks reachable to avoid problems with switching on
|
|
// constants, covered enums, etc.
|
|
// These blocks can contain fall-through annotations, and we don't want to
|
|
// issue a warn_fallthrough_attr_unreachable for them.
|
|
for (const auto *B : *Cfg) {
|
|
const Stmt *L = B->getLabel();
|
|
if (L && isa<SwitchCase>(L) && ReachableBlocks.insert(B).second)
|
|
BlockQueue.push_back(B);
|
|
}
|
|
|
|
while (!BlockQueue.empty()) {
|
|
const CFGBlock *P = BlockQueue.front();
|
|
BlockQueue.pop_front();
|
|
for (CFGBlock::const_succ_iterator I = P->succ_begin(),
|
|
E = P->succ_end();
|
|
I != E; ++I) {
|
|
if (*I && ReachableBlocks.insert(*I).second)
|
|
BlockQueue.push_back(*I);
|
|
}
|
|
}
|
|
}
|
|
|
|
bool checkFallThroughIntoBlock(const CFGBlock &B, int &AnnotatedCnt,
|
|
bool IsTemplateInstantiation) {
|
|
assert(!ReachableBlocks.empty() && "ReachableBlocks empty");
|
|
|
|
int UnannotatedCnt = 0;
|
|
AnnotatedCnt = 0;
|
|
|
|
std::deque<const CFGBlock*> BlockQueue(B.pred_begin(), B.pred_end());
|
|
while (!BlockQueue.empty()) {
|
|
const CFGBlock *P = BlockQueue.front();
|
|
BlockQueue.pop_front();
|
|
if (!P) continue;
|
|
|
|
const Stmt *Term = P->getTerminatorStmt();
|
|
if (Term && isa<SwitchStmt>(Term))
|
|
continue; // Switch statement, good.
|
|
|
|
const SwitchCase *SW = dyn_cast_or_null<SwitchCase>(P->getLabel());
|
|
if (SW && SW->getSubStmt() == B.getLabel() && P->begin() == P->end())
|
|
continue; // Previous case label has no statements, good.
|
|
|
|
const LabelStmt *L = dyn_cast_or_null<LabelStmt>(P->getLabel());
|
|
if (L && L->getSubStmt() == B.getLabel() && P->begin() == P->end())
|
|
continue; // Case label is preceded with a normal label, good.
|
|
|
|
if (!ReachableBlocks.count(P)) {
|
|
for (CFGBlock::const_reverse_iterator ElemIt = P->rbegin(),
|
|
ElemEnd = P->rend();
|
|
ElemIt != ElemEnd; ++ElemIt) {
|
|
if (Optional<CFGStmt> CS = ElemIt->getAs<CFGStmt>()) {
|
|
if (const AttributedStmt *AS = asFallThroughAttr(CS->getStmt())) {
|
|
// Don't issue a warning for an unreachable fallthrough
|
|
// attribute in template instantiations as it may not be
|
|
// unreachable in all instantiations of the template.
|
|
if (!IsTemplateInstantiation)
|
|
S.Diag(AS->getBeginLoc(),
|
|
diag::warn_fallthrough_attr_unreachable);
|
|
markFallthroughVisited(AS);
|
|
++AnnotatedCnt;
|
|
break;
|
|
}
|
|
// Don't care about other unreachable statements.
|
|
}
|
|
}
|
|
// If there are no unreachable statements, this may be a special
|
|
// case in CFG:
|
|
// case X: {
|
|
// A a; // A has a destructor.
|
|
// break;
|
|
// }
|
|
// // <<<< This place is represented by a 'hanging' CFG block.
|
|
// case Y:
|
|
continue;
|
|
}
|
|
|
|
const Stmt *LastStmt = getLastStmt(*P);
|
|
if (const AttributedStmt *AS = asFallThroughAttr(LastStmt)) {
|
|
markFallthroughVisited(AS);
|
|
++AnnotatedCnt;
|
|
continue; // Fallthrough annotation, good.
|
|
}
|
|
|
|
if (!LastStmt) { // This block contains no executable statements.
|
|
// Traverse its predecessors.
|
|
std::copy(P->pred_begin(), P->pred_end(),
|
|
std::back_inserter(BlockQueue));
|
|
continue;
|
|
}
|
|
|
|
++UnannotatedCnt;
|
|
}
|
|
return !!UnannotatedCnt;
|
|
}
|
|
|
|
// RecursiveASTVisitor setup.
|
|
bool shouldWalkTypesOfTypeLocs() const { return false; }
|
|
|
|
bool VisitAttributedStmt(AttributedStmt *S) {
|
|
if (asFallThroughAttr(S))
|
|
FallthroughStmts.insert(S);
|
|
return true;
|
|
}
|
|
|
|
bool VisitSwitchStmt(SwitchStmt *S) {
|
|
FoundSwitchStatements = true;
|
|
return true;
|
|
}
|
|
|
|
// We don't want to traverse local type declarations. We analyze their
|
|
// methods separately.
|
|
bool TraverseDecl(Decl *D) { return true; }
|
|
|
|
// We analyze lambda bodies separately. Skip them here.
|
|
bool TraverseLambdaExpr(LambdaExpr *LE) {
|
|
// Traverse the captures, but not the body.
|
|
for (const auto C : zip(LE->captures(), LE->capture_inits()))
|
|
TraverseLambdaCapture(LE, &std::get<0>(C), std::get<1>(C));
|
|
return true;
|
|
}
|
|
|
|
private:
|
|
|
|
static const AttributedStmt *asFallThroughAttr(const Stmt *S) {
|
|
if (const AttributedStmt *AS = dyn_cast_or_null<AttributedStmt>(S)) {
|
|
if (hasSpecificAttr<FallThroughAttr>(AS->getAttrs()))
|
|
return AS;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
static const Stmt *getLastStmt(const CFGBlock &B) {
|
|
if (const Stmt *Term = B.getTerminatorStmt())
|
|
return Term;
|
|
for (CFGBlock::const_reverse_iterator ElemIt = B.rbegin(),
|
|
ElemEnd = B.rend();
|
|
ElemIt != ElemEnd; ++ElemIt) {
|
|
if (Optional<CFGStmt> CS = ElemIt->getAs<CFGStmt>())
|
|
return CS->getStmt();
|
|
}
|
|
// Workaround to detect a statement thrown out by CFGBuilder:
|
|
// case X: {} case Y:
|
|
// case X: ; case Y:
|
|
if (const SwitchCase *SW = dyn_cast_or_null<SwitchCase>(B.getLabel()))
|
|
if (!isa<SwitchCase>(SW->getSubStmt()))
|
|
return SW->getSubStmt();
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
bool FoundSwitchStatements;
|
|
AttrStmts FallthroughStmts;
|
|
Sema &S;
|
|
llvm::SmallPtrSet<const CFGBlock *, 16> ReachableBlocks;
|
|
};
|
|
} // anonymous namespace
|
|
|
|
static StringRef getFallthroughAttrSpelling(Preprocessor &PP,
|
|
SourceLocation Loc) {
|
|
TokenValue FallthroughTokens[] = {
|
|
tok::l_square, tok::l_square,
|
|
PP.getIdentifierInfo("fallthrough"),
|
|
tok::r_square, tok::r_square
|
|
};
|
|
|
|
TokenValue ClangFallthroughTokens[] = {
|
|
tok::l_square, tok::l_square, PP.getIdentifierInfo("clang"),
|
|
tok::coloncolon, PP.getIdentifierInfo("fallthrough"),
|
|
tok::r_square, tok::r_square
|
|
};
|
|
|
|
bool PreferClangAttr = !PP.getLangOpts().CPlusPlus17 && !PP.getLangOpts().C2x;
|
|
|
|
StringRef MacroName;
|
|
if (PreferClangAttr)
|
|
MacroName = PP.getLastMacroWithSpelling(Loc, ClangFallthroughTokens);
|
|
if (MacroName.empty())
|
|
MacroName = PP.getLastMacroWithSpelling(Loc, FallthroughTokens);
|
|
if (MacroName.empty() && !PreferClangAttr)
|
|
MacroName = PP.getLastMacroWithSpelling(Loc, ClangFallthroughTokens);
|
|
if (MacroName.empty()) {
|
|
if (!PreferClangAttr)
|
|
MacroName = "[[fallthrough]]";
|
|
else if (PP.getLangOpts().CPlusPlus)
|
|
MacroName = "[[clang::fallthrough]]";
|
|
else
|
|
MacroName = "__attribute__((fallthrough))";
|
|
}
|
|
return MacroName;
|
|
}
|
|
|
|
static void DiagnoseSwitchLabelsFallthrough(Sema &S, AnalysisDeclContext &AC,
|
|
bool PerFunction) {
|
|
FallthroughMapper FM(S);
|
|
FM.TraverseStmt(AC.getBody());
|
|
|
|
if (!FM.foundSwitchStatements())
|
|
return;
|
|
|
|
if (PerFunction && FM.getFallthroughStmts().empty())
|
|
return;
|
|
|
|
CFG *Cfg = AC.getCFG();
|
|
|
|
if (!Cfg)
|
|
return;
|
|
|
|
FM.fillReachableBlocks(Cfg);
|
|
|
|
for (const CFGBlock *B : llvm::reverse(*Cfg)) {
|
|
const Stmt *Label = B->getLabel();
|
|
|
|
if (!Label || !isa<SwitchCase>(Label))
|
|
continue;
|
|
|
|
int AnnotatedCnt;
|
|
|
|
bool IsTemplateInstantiation = false;
|
|
if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(AC.getDecl()))
|
|
IsTemplateInstantiation = Function->isTemplateInstantiation();
|
|
if (!FM.checkFallThroughIntoBlock(*B, AnnotatedCnt,
|
|
IsTemplateInstantiation))
|
|
continue;
|
|
|
|
S.Diag(Label->getBeginLoc(),
|
|
PerFunction ? diag::warn_unannotated_fallthrough_per_function
|
|
: diag::warn_unannotated_fallthrough);
|
|
|
|
if (!AnnotatedCnt) {
|
|
SourceLocation L = Label->getBeginLoc();
|
|
if (L.isMacroID())
|
|
continue;
|
|
|
|
const Stmt *Term = B->getTerminatorStmt();
|
|
// Skip empty cases.
|
|
while (B->empty() && !Term && B->succ_size() == 1) {
|
|
B = *B->succ_begin();
|
|
Term = B->getTerminatorStmt();
|
|
}
|
|
if (!(B->empty() && Term && isa<BreakStmt>(Term))) {
|
|
Preprocessor &PP = S.getPreprocessor();
|
|
StringRef AnnotationSpelling = getFallthroughAttrSpelling(PP, L);
|
|
SmallString<64> TextToInsert(AnnotationSpelling);
|
|
TextToInsert += "; ";
|
|
S.Diag(L, diag::note_insert_fallthrough_fixit)
|
|
<< AnnotationSpelling
|
|
<< FixItHint::CreateInsertion(L, TextToInsert);
|
|
}
|
|
S.Diag(L, diag::note_insert_break_fixit)
|
|
<< FixItHint::CreateInsertion(L, "break; ");
|
|
}
|
|
}
|
|
|
|
for (const auto *F : FM.getFallthroughStmts())
|
|
S.Diag(F->getBeginLoc(), diag::err_fallthrough_attr_invalid_placement);
|
|
}
|
|
|
|
static bool isInLoop(const ASTContext &Ctx, const ParentMap &PM,
|
|
const Stmt *S) {
|
|
assert(S);
|
|
|
|
do {
|
|
switch (S->getStmtClass()) {
|
|
case Stmt::ForStmtClass:
|
|
case Stmt::WhileStmtClass:
|
|
case Stmt::CXXForRangeStmtClass:
|
|
case Stmt::ObjCForCollectionStmtClass:
|
|
return true;
|
|
case Stmt::DoStmtClass: {
|
|
Expr::EvalResult Result;
|
|
if (!cast<DoStmt>(S)->getCond()->EvaluateAsInt(Result, Ctx))
|
|
return true;
|
|
return Result.Val.getInt().getBoolValue();
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
} while ((S = PM.getParent(S)));
|
|
|
|
return false;
|
|
}
|
|
|
|
static void diagnoseRepeatedUseOfWeak(Sema &S,
|
|
const sema::FunctionScopeInfo *CurFn,
|
|
const Decl *D,
|
|
const ParentMap &PM) {
|
|
typedef sema::FunctionScopeInfo::WeakObjectProfileTy WeakObjectProfileTy;
|
|
typedef sema::FunctionScopeInfo::WeakObjectUseMap WeakObjectUseMap;
|
|
typedef sema::FunctionScopeInfo::WeakUseVector WeakUseVector;
|
|
typedef std::pair<const Stmt *, WeakObjectUseMap::const_iterator>
|
|
StmtUsesPair;
|
|
|
|
ASTContext &Ctx = S.getASTContext();
|
|
|
|
const WeakObjectUseMap &WeakMap = CurFn->getWeakObjectUses();
|
|
|
|
// Extract all weak objects that are referenced more than once.
|
|
SmallVector<StmtUsesPair, 8> UsesByStmt;
|
|
for (WeakObjectUseMap::const_iterator I = WeakMap.begin(), E = WeakMap.end();
|
|
I != E; ++I) {
|
|
const WeakUseVector &Uses = I->second;
|
|
|
|
// Find the first read of the weak object.
|
|
WeakUseVector::const_iterator UI = Uses.begin(), UE = Uses.end();
|
|
for ( ; UI != UE; ++UI) {
|
|
if (UI->isUnsafe())
|
|
break;
|
|
}
|
|
|
|
// If there were only writes to this object, don't warn.
|
|
if (UI == UE)
|
|
continue;
|
|
|
|
// If there was only one read, followed by any number of writes, and the
|
|
// read is not within a loop, don't warn. Additionally, don't warn in a
|
|
// loop if the base object is a local variable -- local variables are often
|
|
// changed in loops.
|
|
if (UI == Uses.begin()) {
|
|
WeakUseVector::const_iterator UI2 = UI;
|
|
for (++UI2; UI2 != UE; ++UI2)
|
|
if (UI2->isUnsafe())
|
|
break;
|
|
|
|
if (UI2 == UE) {
|
|
if (!isInLoop(Ctx, PM, UI->getUseExpr()))
|
|
continue;
|
|
|
|
const WeakObjectProfileTy &Profile = I->first;
|
|
if (!Profile.isExactProfile())
|
|
continue;
|
|
|
|
const NamedDecl *Base = Profile.getBase();
|
|
if (!Base)
|
|
Base = Profile.getProperty();
|
|
assert(Base && "A profile always has a base or property.");
|
|
|
|
if (const VarDecl *BaseVar = dyn_cast<VarDecl>(Base))
|
|
if (BaseVar->hasLocalStorage() && !isa<ParmVarDecl>(Base))
|
|
continue;
|
|
}
|
|
}
|
|
|
|
UsesByStmt.push_back(StmtUsesPair(UI->getUseExpr(), I));
|
|
}
|
|
|
|
if (UsesByStmt.empty())
|
|
return;
|
|
|
|
// Sort by first use so that we emit the warnings in a deterministic order.
|
|
SourceManager &SM = S.getSourceManager();
|
|
llvm::sort(UsesByStmt,
|
|
[&SM](const StmtUsesPair &LHS, const StmtUsesPair &RHS) {
|
|
return SM.isBeforeInTranslationUnit(LHS.first->getBeginLoc(),
|
|
RHS.first->getBeginLoc());
|
|
});
|
|
|
|
// Classify the current code body for better warning text.
|
|
// This enum should stay in sync with the cases in
|
|
// warn_arc_repeated_use_of_weak and warn_arc_possible_repeated_use_of_weak.
|
|
// FIXME: Should we use a common classification enum and the same set of
|
|
// possibilities all throughout Sema?
|
|
enum {
|
|
Function,
|
|
Method,
|
|
Block,
|
|
Lambda
|
|
} FunctionKind;
|
|
|
|
if (isa<sema::BlockScopeInfo>(CurFn))
|
|
FunctionKind = Block;
|
|
else if (isa<sema::LambdaScopeInfo>(CurFn))
|
|
FunctionKind = Lambda;
|
|
else if (isa<ObjCMethodDecl>(D))
|
|
FunctionKind = Method;
|
|
else
|
|
FunctionKind = Function;
|
|
|
|
// Iterate through the sorted problems and emit warnings for each.
|
|
for (const auto &P : UsesByStmt) {
|
|
const Stmt *FirstRead = P.first;
|
|
const WeakObjectProfileTy &Key = P.second->first;
|
|
const WeakUseVector &Uses = P.second->second;
|
|
|
|
// For complicated expressions like 'a.b.c' and 'x.b.c', WeakObjectProfileTy
|
|
// may not contain enough information to determine that these are different
|
|
// properties. We can only be 100% sure of a repeated use in certain cases,
|
|
// and we adjust the diagnostic kind accordingly so that the less certain
|
|
// case can be turned off if it is too noisy.
|
|
unsigned DiagKind;
|
|
if (Key.isExactProfile())
|
|
DiagKind = diag::warn_arc_repeated_use_of_weak;
|
|
else
|
|
DiagKind = diag::warn_arc_possible_repeated_use_of_weak;
|
|
|
|
// Classify the weak object being accessed for better warning text.
|
|
// This enum should stay in sync with the cases in
|
|
// warn_arc_repeated_use_of_weak and warn_arc_possible_repeated_use_of_weak.
|
|
enum {
|
|
Variable,
|
|
Property,
|
|
ImplicitProperty,
|
|
Ivar
|
|
} ObjectKind;
|
|
|
|
const NamedDecl *KeyProp = Key.getProperty();
|
|
if (isa<VarDecl>(KeyProp))
|
|
ObjectKind = Variable;
|
|
else if (isa<ObjCPropertyDecl>(KeyProp))
|
|
ObjectKind = Property;
|
|
else if (isa<ObjCMethodDecl>(KeyProp))
|
|
ObjectKind = ImplicitProperty;
|
|
else if (isa<ObjCIvarDecl>(KeyProp))
|
|
ObjectKind = Ivar;
|
|
else
|
|
llvm_unreachable("Unexpected weak object kind!");
|
|
|
|
// Do not warn about IBOutlet weak property receivers being set to null
|
|
// since they are typically only used from the main thread.
|
|
if (const ObjCPropertyDecl *Prop = dyn_cast<ObjCPropertyDecl>(KeyProp))
|
|
if (Prop->hasAttr<IBOutletAttr>())
|
|
continue;
|
|
|
|
// Show the first time the object was read.
|
|
S.Diag(FirstRead->getBeginLoc(), DiagKind)
|
|
<< int(ObjectKind) << KeyProp << int(FunctionKind)
|
|
<< FirstRead->getSourceRange();
|
|
|
|
// Print all the other accesses as notes.
|
|
for (const auto &Use : Uses) {
|
|
if (Use.getUseExpr() == FirstRead)
|
|
continue;
|
|
S.Diag(Use.getUseExpr()->getBeginLoc(),
|
|
diag::note_arc_weak_also_accessed_here)
|
|
<< Use.getUseExpr()->getSourceRange();
|
|
}
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
class UninitValsDiagReporter : public UninitVariablesHandler {
|
|
Sema &S;
|
|
typedef SmallVector<UninitUse, 2> UsesVec;
|
|
typedef llvm::PointerIntPair<UsesVec *, 1, bool> MappedType;
|
|
// Prefer using MapVector to DenseMap, so that iteration order will be
|
|
// the same as insertion order. This is needed to obtain a deterministic
|
|
// order of diagnostics when calling flushDiagnostics().
|
|
typedef llvm::MapVector<const VarDecl *, MappedType> UsesMap;
|
|
UsesMap uses;
|
|
UsesMap constRefUses;
|
|
|
|
public:
|
|
UninitValsDiagReporter(Sema &S) : S(S) {}
|
|
~UninitValsDiagReporter() override { flushDiagnostics(); }
|
|
|
|
MappedType &getUses(UsesMap &um, const VarDecl *vd) {
|
|
MappedType &V = um[vd];
|
|
if (!V.getPointer())
|
|
V.setPointer(new UsesVec());
|
|
return V;
|
|
}
|
|
|
|
void handleUseOfUninitVariable(const VarDecl *vd,
|
|
const UninitUse &use) override {
|
|
getUses(uses, vd).getPointer()->push_back(use);
|
|
}
|
|
|
|
void handleConstRefUseOfUninitVariable(const VarDecl *vd,
|
|
const UninitUse &use) override {
|
|
getUses(constRefUses, vd).getPointer()->push_back(use);
|
|
}
|
|
|
|
void handleSelfInit(const VarDecl *vd) override {
|
|
getUses(uses, vd).setInt(true);
|
|
getUses(constRefUses, vd).setInt(true);
|
|
}
|
|
|
|
void flushDiagnostics() {
|
|
for (const auto &P : uses) {
|
|
const VarDecl *vd = P.first;
|
|
const MappedType &V = P.second;
|
|
|
|
UsesVec *vec = V.getPointer();
|
|
bool hasSelfInit = V.getInt();
|
|
|
|
// Specially handle the case where we have uses of an uninitialized
|
|
// variable, but the root cause is an idiomatic self-init. We want
|
|
// to report the diagnostic at the self-init since that is the root cause.
|
|
if (!vec->empty() && hasSelfInit && hasAlwaysUninitializedUse(vec))
|
|
DiagnoseUninitializedUse(S, vd,
|
|
UninitUse(vd->getInit()->IgnoreParenCasts(),
|
|
/* isAlwaysUninit */ true),
|
|
/* alwaysReportSelfInit */ true);
|
|
else {
|
|
// Sort the uses by their SourceLocations. While not strictly
|
|
// guaranteed to produce them in line/column order, this will provide
|
|
// a stable ordering.
|
|
llvm::sort(vec->begin(), vec->end(),
|
|
[](const UninitUse &a, const UninitUse &b) {
|
|
// Prefer a more confident report over a less confident one.
|
|
if (a.getKind() != b.getKind())
|
|
return a.getKind() > b.getKind();
|
|
return a.getUser()->getBeginLoc() < b.getUser()->getBeginLoc();
|
|
});
|
|
|
|
for (const auto &U : *vec) {
|
|
// If we have self-init, downgrade all uses to 'may be uninitialized'.
|
|
UninitUse Use = hasSelfInit ? UninitUse(U.getUser(), false) : U;
|
|
|
|
if (DiagnoseUninitializedUse(S, vd, Use))
|
|
// Skip further diagnostics for this variable. We try to warn only
|
|
// on the first point at which a variable is used uninitialized.
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Release the uses vector.
|
|
delete vec;
|
|
}
|
|
|
|
uses.clear();
|
|
|
|
// Flush all const reference uses diags.
|
|
for (const auto &P : constRefUses) {
|
|
const VarDecl *vd = P.first;
|
|
const MappedType &V = P.second;
|
|
|
|
UsesVec *vec = V.getPointer();
|
|
bool hasSelfInit = V.getInt();
|
|
|
|
if (!vec->empty() && hasSelfInit && hasAlwaysUninitializedUse(vec))
|
|
DiagnoseUninitializedUse(S, vd,
|
|
UninitUse(vd->getInit()->IgnoreParenCasts(),
|
|
/* isAlwaysUninit */ true),
|
|
/* alwaysReportSelfInit */ true);
|
|
else {
|
|
for (const auto &U : *vec) {
|
|
if (DiagnoseUninitializedConstRefUse(S, vd, U))
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Release the uses vector.
|
|
delete vec;
|
|
}
|
|
|
|
constRefUses.clear();
|
|
}
|
|
|
|
private:
|
|
static bool hasAlwaysUninitializedUse(const UsesVec* vec) {
|
|
return std::any_of(vec->begin(), vec->end(), [](const UninitUse &U) {
|
|
return U.getKind() == UninitUse::Always ||
|
|
U.getKind() == UninitUse::AfterCall ||
|
|
U.getKind() == UninitUse::AfterDecl;
|
|
});
|
|
}
|
|
};
|
|
} // anonymous namespace
|
|
|
|
namespace clang {
|
|
namespace {
|
|
typedef SmallVector<PartialDiagnosticAt, 1> OptionalNotes;
|
|
typedef std::pair<PartialDiagnosticAt, OptionalNotes> DelayedDiag;
|
|
typedef std::list<DelayedDiag> DiagList;
|
|
|
|
struct SortDiagBySourceLocation {
|
|
SourceManager &SM;
|
|
SortDiagBySourceLocation(SourceManager &SM) : SM(SM) {}
|
|
|
|
bool operator()(const DelayedDiag &left, const DelayedDiag &right) {
|
|
// Although this call will be slow, this is only called when outputting
|
|
// multiple warnings.
|
|
return SM.isBeforeInTranslationUnit(left.first.first, right.first.first);
|
|
}
|
|
};
|
|
} // anonymous namespace
|
|
} // namespace clang
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// -Wthread-safety
|
|
//===----------------------------------------------------------------------===//
|
|
namespace clang {
|
|
namespace threadSafety {
|
|
namespace {
|
|
class ThreadSafetyReporter : public clang::threadSafety::ThreadSafetyHandler {
|
|
Sema &S;
|
|
DiagList Warnings;
|
|
SourceLocation FunLocation, FunEndLocation;
|
|
|
|
const FunctionDecl *CurrentFunction;
|
|
bool Verbose;
|
|
|
|
OptionalNotes getNotes() const {
|
|
if (Verbose && CurrentFunction) {
|
|
PartialDiagnosticAt FNote(CurrentFunction->getBody()->getBeginLoc(),
|
|
S.PDiag(diag::note_thread_warning_in_fun)
|
|
<< CurrentFunction);
|
|
return OptionalNotes(1, FNote);
|
|
}
|
|
return OptionalNotes();
|
|
}
|
|
|
|
OptionalNotes getNotes(const PartialDiagnosticAt &Note) const {
|
|
OptionalNotes ONS(1, Note);
|
|
if (Verbose && CurrentFunction) {
|
|
PartialDiagnosticAt FNote(CurrentFunction->getBody()->getBeginLoc(),
|
|
S.PDiag(diag::note_thread_warning_in_fun)
|
|
<< CurrentFunction);
|
|
ONS.push_back(std::move(FNote));
|
|
}
|
|
return ONS;
|
|
}
|
|
|
|
OptionalNotes getNotes(const PartialDiagnosticAt &Note1,
|
|
const PartialDiagnosticAt &Note2) const {
|
|
OptionalNotes ONS;
|
|
ONS.push_back(Note1);
|
|
ONS.push_back(Note2);
|
|
if (Verbose && CurrentFunction) {
|
|
PartialDiagnosticAt FNote(CurrentFunction->getBody()->getBeginLoc(),
|
|
S.PDiag(diag::note_thread_warning_in_fun)
|
|
<< CurrentFunction);
|
|
ONS.push_back(std::move(FNote));
|
|
}
|
|
return ONS;
|
|
}
|
|
|
|
OptionalNotes makeLockedHereNote(SourceLocation LocLocked, StringRef Kind) {
|
|
return LocLocked.isValid()
|
|
? getNotes(PartialDiagnosticAt(
|
|
LocLocked, S.PDiag(diag::note_locked_here) << Kind))
|
|
: getNotes();
|
|
}
|
|
|
|
OptionalNotes makeUnlockedHereNote(SourceLocation LocUnlocked,
|
|
StringRef Kind) {
|
|
return LocUnlocked.isValid()
|
|
? getNotes(PartialDiagnosticAt(
|
|
LocUnlocked, S.PDiag(diag::note_unlocked_here) << Kind))
|
|
: getNotes();
|
|
}
|
|
|
|
public:
|
|
ThreadSafetyReporter(Sema &S, SourceLocation FL, SourceLocation FEL)
|
|
: S(S), FunLocation(FL), FunEndLocation(FEL),
|
|
CurrentFunction(nullptr), Verbose(false) {}
|
|
|
|
void setVerbose(bool b) { Verbose = b; }
|
|
|
|
/// Emit all buffered diagnostics in order of sourcelocation.
|
|
/// We need to output diagnostics produced while iterating through
|
|
/// the lockset in deterministic order, so this function orders diagnostics
|
|
/// and outputs them.
|
|
void emitDiagnostics() {
|
|
Warnings.sort(SortDiagBySourceLocation(S.getSourceManager()));
|
|
for (const auto &Diag : Warnings) {
|
|
S.Diag(Diag.first.first, Diag.first.second);
|
|
for (const auto &Note : Diag.second)
|
|
S.Diag(Note.first, Note.second);
|
|
}
|
|
}
|
|
|
|
void handleInvalidLockExp(StringRef Kind, SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_cannot_resolve_lock)
|
|
<< Loc);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleUnmatchedUnlock(StringRef Kind, Name LockName, SourceLocation Loc,
|
|
SourceLocation LocPreviousUnlock) override {
|
|
if (Loc.isInvalid())
|
|
Loc = FunLocation;
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_unlock_but_no_lock)
|
|
<< Kind << LockName);
|
|
Warnings.emplace_back(std::move(Warning),
|
|
makeUnlockedHereNote(LocPreviousUnlock, Kind));
|
|
}
|
|
|
|
void handleIncorrectUnlockKind(StringRef Kind, Name LockName,
|
|
LockKind Expected, LockKind Received,
|
|
SourceLocation LocLocked,
|
|
SourceLocation LocUnlock) override {
|
|
if (LocUnlock.isInvalid())
|
|
LocUnlock = FunLocation;
|
|
PartialDiagnosticAt Warning(
|
|
LocUnlock, S.PDiag(diag::warn_unlock_kind_mismatch)
|
|
<< Kind << LockName << Received << Expected);
|
|
Warnings.emplace_back(std::move(Warning),
|
|
makeLockedHereNote(LocLocked, Kind));
|
|
}
|
|
|
|
void handleDoubleLock(StringRef Kind, Name LockName, SourceLocation LocLocked,
|
|
SourceLocation LocDoubleLock) override {
|
|
if (LocDoubleLock.isInvalid())
|
|
LocDoubleLock = FunLocation;
|
|
PartialDiagnosticAt Warning(LocDoubleLock, S.PDiag(diag::warn_double_lock)
|
|
<< Kind << LockName);
|
|
Warnings.emplace_back(std::move(Warning),
|
|
makeLockedHereNote(LocLocked, Kind));
|
|
}
|
|
|
|
void handleMutexHeldEndOfScope(StringRef Kind, Name LockName,
|
|
SourceLocation LocLocked,
|
|
SourceLocation LocEndOfScope,
|
|
LockErrorKind LEK) override {
|
|
unsigned DiagID = 0;
|
|
switch (LEK) {
|
|
case LEK_LockedSomePredecessors:
|
|
DiagID = diag::warn_lock_some_predecessors;
|
|
break;
|
|
case LEK_LockedSomeLoopIterations:
|
|
DiagID = diag::warn_expecting_lock_held_on_loop;
|
|
break;
|
|
case LEK_LockedAtEndOfFunction:
|
|
DiagID = diag::warn_no_unlock;
|
|
break;
|
|
case LEK_NotLockedAtEndOfFunction:
|
|
DiagID = diag::warn_expecting_locked;
|
|
break;
|
|
}
|
|
if (LocEndOfScope.isInvalid())
|
|
LocEndOfScope = FunEndLocation;
|
|
|
|
PartialDiagnosticAt Warning(LocEndOfScope, S.PDiag(DiagID) << Kind
|
|
<< LockName);
|
|
Warnings.emplace_back(std::move(Warning),
|
|
makeLockedHereNote(LocLocked, Kind));
|
|
}
|
|
|
|
void handleExclusiveAndShared(StringRef Kind, Name LockName,
|
|
SourceLocation Loc1,
|
|
SourceLocation Loc2) override {
|
|
PartialDiagnosticAt Warning(Loc1,
|
|
S.PDiag(diag::warn_lock_exclusive_and_shared)
|
|
<< Kind << LockName);
|
|
PartialDiagnosticAt Note(Loc2, S.PDiag(diag::note_lock_exclusive_and_shared)
|
|
<< Kind << LockName);
|
|
Warnings.emplace_back(std::move(Warning), getNotes(Note));
|
|
}
|
|
|
|
void handleNoMutexHeld(StringRef Kind, const NamedDecl *D,
|
|
ProtectedOperationKind POK, AccessKind AK,
|
|
SourceLocation Loc) override {
|
|
assert((POK == POK_VarAccess || POK == POK_VarDereference) &&
|
|
"Only works for variables");
|
|
unsigned DiagID = POK == POK_VarAccess?
|
|
diag::warn_variable_requires_any_lock:
|
|
diag::warn_var_deref_requires_any_lock;
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID)
|
|
<< D << getLockKindFromAccessKind(AK));
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleMutexNotHeld(StringRef Kind, const NamedDecl *D,
|
|
ProtectedOperationKind POK, Name LockName,
|
|
LockKind LK, SourceLocation Loc,
|
|
Name *PossibleMatch) override {
|
|
unsigned DiagID = 0;
|
|
if (PossibleMatch) {
|
|
switch (POK) {
|
|
case POK_VarAccess:
|
|
DiagID = diag::warn_variable_requires_lock_precise;
|
|
break;
|
|
case POK_VarDereference:
|
|
DiagID = diag::warn_var_deref_requires_lock_precise;
|
|
break;
|
|
case POK_FunctionCall:
|
|
DiagID = diag::warn_fun_requires_lock_precise;
|
|
break;
|
|
case POK_PassByRef:
|
|
DiagID = diag::warn_guarded_pass_by_reference;
|
|
break;
|
|
case POK_PtPassByRef:
|
|
DiagID = diag::warn_pt_guarded_pass_by_reference;
|
|
break;
|
|
}
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << Kind
|
|
<< D
|
|
<< LockName << LK);
|
|
PartialDiagnosticAt Note(Loc, S.PDiag(diag::note_found_mutex_near_match)
|
|
<< *PossibleMatch);
|
|
if (Verbose && POK == POK_VarAccess) {
|
|
PartialDiagnosticAt VNote(D->getLocation(),
|
|
S.PDiag(diag::note_guarded_by_declared_here)
|
|
<< D->getDeclName());
|
|
Warnings.emplace_back(std::move(Warning), getNotes(Note, VNote));
|
|
} else
|
|
Warnings.emplace_back(std::move(Warning), getNotes(Note));
|
|
} else {
|
|
switch (POK) {
|
|
case POK_VarAccess:
|
|
DiagID = diag::warn_variable_requires_lock;
|
|
break;
|
|
case POK_VarDereference:
|
|
DiagID = diag::warn_var_deref_requires_lock;
|
|
break;
|
|
case POK_FunctionCall:
|
|
DiagID = diag::warn_fun_requires_lock;
|
|
break;
|
|
case POK_PassByRef:
|
|
DiagID = diag::warn_guarded_pass_by_reference;
|
|
break;
|
|
case POK_PtPassByRef:
|
|
DiagID = diag::warn_pt_guarded_pass_by_reference;
|
|
break;
|
|
}
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << Kind
|
|
<< D
|
|
<< LockName << LK);
|
|
if (Verbose && POK == POK_VarAccess) {
|
|
PartialDiagnosticAt Note(D->getLocation(),
|
|
S.PDiag(diag::note_guarded_by_declared_here));
|
|
Warnings.emplace_back(std::move(Warning), getNotes(Note));
|
|
} else
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
}
|
|
|
|
void handleNegativeNotHeld(StringRef Kind, Name LockName, Name Neg,
|
|
SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(Loc,
|
|
S.PDiag(diag::warn_acquire_requires_negative_cap)
|
|
<< Kind << LockName << Neg);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleNegativeNotHeld(const NamedDecl *D, Name LockName,
|
|
SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(
|
|
Loc, S.PDiag(diag::warn_fun_requires_negative_cap) << D << LockName);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleFunExcludesLock(StringRef Kind, Name FunName, Name LockName,
|
|
SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_fun_excludes_mutex)
|
|
<< Kind << FunName << LockName);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleLockAcquiredBefore(StringRef Kind, Name L1Name, Name L2Name,
|
|
SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(Loc,
|
|
S.PDiag(diag::warn_acquired_before) << Kind << L1Name << L2Name);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void handleBeforeAfterCycle(Name L1Name, SourceLocation Loc) override {
|
|
PartialDiagnosticAt Warning(Loc,
|
|
S.PDiag(diag::warn_acquired_before_after_cycle) << L1Name);
|
|
Warnings.emplace_back(std::move(Warning), getNotes());
|
|
}
|
|
|
|
void enterFunction(const FunctionDecl* FD) override {
|
|
CurrentFunction = FD;
|
|
}
|
|
|
|
void leaveFunction(const FunctionDecl* FD) override {
|
|
CurrentFunction = nullptr;
|
|
}
|
|
};
|
|
} // anonymous namespace
|
|
} // namespace threadSafety
|
|
} // namespace clang
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// -Wconsumed
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace clang {
|
|
namespace consumed {
|
|
namespace {
|
|
class ConsumedWarningsHandler : public ConsumedWarningsHandlerBase {
|
|
|
|
Sema &S;
|
|
DiagList Warnings;
|
|
|
|
public:
|
|
|
|
ConsumedWarningsHandler(Sema &S) : S(S) {}
|
|
|
|
void emitDiagnostics() override {
|
|
Warnings.sort(SortDiagBySourceLocation(S.getSourceManager()));
|
|
for (const auto &Diag : Warnings) {
|
|
S.Diag(Diag.first.first, Diag.first.second);
|
|
for (const auto &Note : Diag.second)
|
|
S.Diag(Note.first, Note.second);
|
|
}
|
|
}
|
|
|
|
void warnLoopStateMismatch(SourceLocation Loc,
|
|
StringRef VariableName) override {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_loop_state_mismatch) <<
|
|
VariableName);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnParamReturnTypestateMismatch(SourceLocation Loc,
|
|
StringRef VariableName,
|
|
StringRef ExpectedState,
|
|
StringRef ObservedState) override {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_param_return_typestate_mismatch) << VariableName <<
|
|
ExpectedState << ObservedState);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnParamTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
|
|
StringRef ObservedState) override {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_param_typestate_mismatch) << ExpectedState << ObservedState);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnReturnTypestateForUnconsumableType(SourceLocation Loc,
|
|
StringRef TypeName) override {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_return_typestate_for_unconsumable_type) << TypeName);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnReturnTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
|
|
StringRef ObservedState) override {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_return_typestate_mismatch) << ExpectedState << ObservedState);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnUseOfTempInInvalidState(StringRef MethodName, StringRef State,
|
|
SourceLocation Loc) override {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_use_of_temp_in_invalid_state) << MethodName << State);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
|
|
void warnUseInInvalidState(StringRef MethodName, StringRef VariableName,
|
|
StringRef State, SourceLocation Loc) override {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_use_in_invalid_state) <<
|
|
MethodName << VariableName << State);
|
|
|
|
Warnings.emplace_back(std::move(Warning), OptionalNotes());
|
|
}
|
|
};
|
|
} // anonymous namespace
|
|
} // namespace consumed
|
|
} // namespace clang
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// 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;
|
|
enableThreadSafetyAnalysis = 0;
|
|
enableConsumedAnalysis = 0;
|
|
}
|
|
|
|
static unsigned isEnabled(DiagnosticsEngine &D, unsigned diag) {
|
|
return (unsigned)!D.isIgnored(diag, SourceLocation());
|
|
}
|
|
|
|
clang::sema::AnalysisBasedWarnings::AnalysisBasedWarnings(Sema &s)
|
|
: S(s),
|
|
NumFunctionsAnalyzed(0),
|
|
NumFunctionsWithBadCFGs(0),
|
|
NumCFGBlocks(0),
|
|
MaxCFGBlocksPerFunction(0),
|
|
NumUninitAnalysisFunctions(0),
|
|
NumUninitAnalysisVariables(0),
|
|
MaxUninitAnalysisVariablesPerFunction(0),
|
|
NumUninitAnalysisBlockVisits(0),
|
|
MaxUninitAnalysisBlockVisitsPerFunction(0) {
|
|
|
|
using namespace diag;
|
|
DiagnosticsEngine &D = S.getDiagnostics();
|
|
|
|
DefaultPolicy.enableCheckUnreachable =
|
|
isEnabled(D, warn_unreachable) ||
|
|
isEnabled(D, warn_unreachable_break) ||
|
|
isEnabled(D, warn_unreachable_return) ||
|
|
isEnabled(D, warn_unreachable_loop_increment);
|
|
|
|
DefaultPolicy.enableThreadSafetyAnalysis =
|
|
isEnabled(D, warn_double_lock);
|
|
|
|
DefaultPolicy.enableConsumedAnalysis =
|
|
isEnabled(D, warn_use_in_invalid_state);
|
|
}
|
|
|
|
static void flushDiagnostics(Sema &S, const sema::FunctionScopeInfo *fscope) {
|
|
for (const auto &D : fscope->PossiblyUnreachableDiags)
|
|
S.Diag(D.Loc, D.PD);
|
|
}
|
|
|
|
void clang::sema::
|
|
AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
|
|
sema::FunctionScopeInfo *fscope,
|
|
const Decl *D, QualType BlockType) {
|
|
|
|
// 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.
|
|
DiagnosticsEngine &Diags = S.getDiagnostics();
|
|
|
|
// Do not do any analysis if we are going to just ignore them.
|
|
if (Diags.getIgnoreAllWarnings() ||
|
|
(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 (S.hasUncompilableErrorOccurred()) {
|
|
// Flush out any possibly unreachable diagnostics.
|
|
flushDiagnostics(S, fscope);
|
|
return;
|
|
}
|
|
|
|
const Stmt *Body = D->getBody();
|
|
assert(Body);
|
|
|
|
// Construct the analysis context with the specified CFG build options.
|
|
AnalysisDeclContext AC(/* AnalysisDeclContextManager */ nullptr, D);
|
|
|
|
// Don't generate EH edges for CallExprs as we'd like to avoid the n^2
|
|
// explosion for destructors that can result and the compile time hit.
|
|
AC.getCFGBuildOptions().PruneTriviallyFalseEdges = true;
|
|
AC.getCFGBuildOptions().AddEHEdges = false;
|
|
AC.getCFGBuildOptions().AddInitializers = true;
|
|
AC.getCFGBuildOptions().AddImplicitDtors = true;
|
|
AC.getCFGBuildOptions().AddTemporaryDtors = true;
|
|
AC.getCFGBuildOptions().AddCXXNewAllocator = false;
|
|
AC.getCFGBuildOptions().AddCXXDefaultInitExprInCtors = true;
|
|
|
|
// Force that certain expressions appear as CFGElements in the CFG. This
|
|
// is used to speed up various analyses.
|
|
// FIXME: This isn't the right factoring. This is here for initial
|
|
// prototyping, but we need a way for analyses to say what expressions they
|
|
// expect to always be CFGElements and then fill in the BuildOptions
|
|
// appropriately. This is essentially a layering violation.
|
|
if (P.enableCheckUnreachable || P.enableThreadSafetyAnalysis ||
|
|
P.enableConsumedAnalysis) {
|
|
// Unreachable code analysis and thread safety require a linearized CFG.
|
|
AC.getCFGBuildOptions().setAllAlwaysAdd();
|
|
}
|
|
else {
|
|
AC.getCFGBuildOptions()
|
|
.setAlwaysAdd(Stmt::BinaryOperatorClass)
|
|
.setAlwaysAdd(Stmt::CompoundAssignOperatorClass)
|
|
.setAlwaysAdd(Stmt::BlockExprClass)
|
|
.setAlwaysAdd(Stmt::CStyleCastExprClass)
|
|
.setAlwaysAdd(Stmt::DeclRefExprClass)
|
|
.setAlwaysAdd(Stmt::ImplicitCastExprClass)
|
|
.setAlwaysAdd(Stmt::UnaryOperatorClass)
|
|
.setAlwaysAdd(Stmt::AttributedStmtClass);
|
|
}
|
|
|
|
// Install the logical handler.
|
|
llvm::Optional<LogicalErrorHandler> LEH;
|
|
if (LogicalErrorHandler::hasActiveDiagnostics(Diags, D->getBeginLoc())) {
|
|
LEH.emplace(S);
|
|
AC.getCFGBuildOptions().Observer = &*LEH;
|
|
}
|
|
|
|
// Emit delayed diagnostics.
|
|
if (!fscope->PossiblyUnreachableDiags.empty()) {
|
|
bool analyzed = false;
|
|
|
|
// Register the expressions with the CFGBuilder.
|
|
for (const auto &D : fscope->PossiblyUnreachableDiags) {
|
|
for (const Stmt *S : D.Stmts)
|
|
AC.registerForcedBlockExpression(S);
|
|
}
|
|
|
|
if (AC.getCFG()) {
|
|
analyzed = true;
|
|
for (const auto &D : fscope->PossiblyUnreachableDiags) {
|
|
bool AllReachable = true;
|
|
for (const Stmt *S : D.Stmts) {
|
|
const CFGBlock *block = AC.getBlockForRegisteredExpression(S);
|
|
CFGReverseBlockReachabilityAnalysis *cra =
|
|
AC.getCFGReachablityAnalysis();
|
|
// FIXME: We should be able to assert that block is non-null, but
|
|
// the CFG analysis can skip potentially-evaluated expressions in
|
|
// edge cases; see test/Sema/vla-2.c.
|
|
if (block && cra) {
|
|
// Can this block be reached from the entrance?
|
|
if (!cra->isReachable(&AC.getCFG()->getEntry(), block)) {
|
|
AllReachable = false;
|
|
break;
|
|
}
|
|
}
|
|
// If we cannot map to a basic block, assume the statement is
|
|
// reachable.
|
|
}
|
|
|
|
if (AllReachable)
|
|
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()
|
|
: (isa<CXXMethodDecl>(D) &&
|
|
cast<CXXMethodDecl>(D)->getOverloadedOperator() == OO_Call &&
|
|
cast<CXXMethodDecl>(D)->getParent()->isLambda())
|
|
? CheckFallThroughDiagnostics::MakeForLambda()
|
|
: (fscope->isCoroutine()
|
|
? CheckFallThroughDiagnostics::MakeForCoroutine(D)
|
|
: CheckFallThroughDiagnostics::MakeForFunction(D)));
|
|
CheckFallThroughForBody(S, D, Body, BlockType, CD, AC, fscope);
|
|
}
|
|
|
|
// Warning: check for unreachable code
|
|
if (P.enableCheckUnreachable) {
|
|
// Only check for unreachable code on non-template instantiations.
|
|
// Different template instantiations can effectively change the control-flow
|
|
// and it is very difficult to prove that a snippet of code in a template
|
|
// is unreachable for all instantiations.
|
|
bool isTemplateInstantiation = false;
|
|
if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
|
|
isTemplateInstantiation = Function->isTemplateInstantiation();
|
|
if (!isTemplateInstantiation)
|
|
CheckUnreachable(S, AC);
|
|
}
|
|
|
|
// Check for thread safety violations
|
|
if (P.enableThreadSafetyAnalysis) {
|
|
SourceLocation FL = AC.getDecl()->getLocation();
|
|
SourceLocation FEL = AC.getDecl()->getEndLoc();
|
|
threadSafety::ThreadSafetyReporter Reporter(S, FL, FEL);
|
|
if (!Diags.isIgnored(diag::warn_thread_safety_beta, D->getBeginLoc()))
|
|
Reporter.setIssueBetaWarnings(true);
|
|
if (!Diags.isIgnored(diag::warn_thread_safety_verbose, D->getBeginLoc()))
|
|
Reporter.setVerbose(true);
|
|
|
|
threadSafety::runThreadSafetyAnalysis(AC, Reporter,
|
|
&S.ThreadSafetyDeclCache);
|
|
Reporter.emitDiagnostics();
|
|
}
|
|
|
|
// Check for violations of consumed properties.
|
|
if (P.enableConsumedAnalysis) {
|
|
consumed::ConsumedWarningsHandler WarningHandler(S);
|
|
consumed::ConsumedAnalyzer Analyzer(WarningHandler);
|
|
Analyzer.run(AC);
|
|
}
|
|
|
|
if (!Diags.isIgnored(diag::warn_uninit_var, D->getBeginLoc()) ||
|
|
!Diags.isIgnored(diag::warn_sometimes_uninit_var, D->getBeginLoc()) ||
|
|
!Diags.isIgnored(diag::warn_maybe_uninit_var, D->getBeginLoc()) ||
|
|
!Diags.isIgnored(diag::warn_uninit_const_reference, D->getBeginLoc())) {
|
|
if (CFG *cfg = AC.getCFG()) {
|
|
UninitValsDiagReporter reporter(S);
|
|
UninitVariablesAnalysisStats stats;
|
|
std::memset(&stats, 0, sizeof(UninitVariablesAnalysisStats));
|
|
runUninitializedVariablesAnalysis(*cast<DeclContext>(D), *cfg, AC,
|
|
reporter, stats);
|
|
|
|
if (S.CollectStats && stats.NumVariablesAnalyzed > 0) {
|
|
++NumUninitAnalysisFunctions;
|
|
NumUninitAnalysisVariables += stats.NumVariablesAnalyzed;
|
|
NumUninitAnalysisBlockVisits += stats.NumBlockVisits;
|
|
MaxUninitAnalysisVariablesPerFunction =
|
|
std::max(MaxUninitAnalysisVariablesPerFunction,
|
|
stats.NumVariablesAnalyzed);
|
|
MaxUninitAnalysisBlockVisitsPerFunction =
|
|
std::max(MaxUninitAnalysisBlockVisitsPerFunction,
|
|
stats.NumBlockVisits);
|
|
}
|
|
}
|
|
}
|
|
|
|
bool FallThroughDiagFull =
|
|
!Diags.isIgnored(diag::warn_unannotated_fallthrough, D->getBeginLoc());
|
|
bool FallThroughDiagPerFunction = !Diags.isIgnored(
|
|
diag::warn_unannotated_fallthrough_per_function, D->getBeginLoc());
|
|
if (FallThroughDiagFull || FallThroughDiagPerFunction ||
|
|
fscope->HasFallthroughStmt) {
|
|
DiagnoseSwitchLabelsFallthrough(S, AC, !FallThroughDiagFull);
|
|
}
|
|
|
|
if (S.getLangOpts().ObjCWeak &&
|
|
!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, D->getBeginLoc()))
|
|
diagnoseRepeatedUseOfWeak(S, fscope, D, AC.getParentMap());
|
|
|
|
|
|
// Check for infinite self-recursion in functions
|
|
if (!Diags.isIgnored(diag::warn_infinite_recursive_function,
|
|
D->getBeginLoc())) {
|
|
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
|
|
checkRecursiveFunction(S, FD, Body, AC);
|
|
}
|
|
}
|
|
|
|
// Check for throw out of non-throwing function.
|
|
if (!Diags.isIgnored(diag::warn_throw_in_noexcept_func, D->getBeginLoc()))
|
|
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
|
|
if (S.getLangOpts().CPlusPlus && isNoexcept(FD))
|
|
checkThrowInNonThrowingFunc(S, FD, AC);
|
|
|
|
// If none of the previous checks caused a CFG build, trigger one here
|
|
// for the logical error handler.
|
|
if (LogicalErrorHandler::hasActiveDiagnostics(Diags, D->getBeginLoc())) {
|
|
AC.getCFG();
|
|
}
|
|
|
|
// Collect statistics about the CFG if it was built.
|
|
if (S.CollectStats && AC.isCFGBuilt()) {
|
|
++NumFunctionsAnalyzed;
|
|
if (CFG *cfg = AC.getCFG()) {
|
|
// If we successfully built a CFG for this context, record some more
|
|
// detail information about it.
|
|
NumCFGBlocks += cfg->getNumBlockIDs();
|
|
MaxCFGBlocksPerFunction = std::max(MaxCFGBlocksPerFunction,
|
|
cfg->getNumBlockIDs());
|
|
} else {
|
|
++NumFunctionsWithBadCFGs;
|
|
}
|
|
}
|
|
}
|
|
|
|
void clang::sema::AnalysisBasedWarnings::PrintStats() const {
|
|
llvm::errs() << "\n*** Analysis Based Warnings Stats:\n";
|
|
|
|
unsigned NumCFGsBuilt = NumFunctionsAnalyzed - NumFunctionsWithBadCFGs;
|
|
unsigned AvgCFGBlocksPerFunction =
|
|
!NumCFGsBuilt ? 0 : NumCFGBlocks/NumCFGsBuilt;
|
|
llvm::errs() << NumFunctionsAnalyzed << " functions analyzed ("
|
|
<< NumFunctionsWithBadCFGs << " w/o CFGs).\n"
|
|
<< " " << NumCFGBlocks << " CFG blocks built.\n"
|
|
<< " " << AvgCFGBlocksPerFunction
|
|
<< " average CFG blocks per function.\n"
|
|
<< " " << MaxCFGBlocksPerFunction
|
|
<< " max CFG blocks per function.\n";
|
|
|
|
unsigned AvgUninitVariablesPerFunction = !NumUninitAnalysisFunctions ? 0
|
|
: NumUninitAnalysisVariables/NumUninitAnalysisFunctions;
|
|
unsigned AvgUninitBlockVisitsPerFunction = !NumUninitAnalysisFunctions ? 0
|
|
: NumUninitAnalysisBlockVisits/NumUninitAnalysisFunctions;
|
|
llvm::errs() << NumUninitAnalysisFunctions
|
|
<< " functions analyzed for uninitialiazed variables\n"
|
|
<< " " << NumUninitAnalysisVariables << " variables analyzed.\n"
|
|
<< " " << AvgUninitVariablesPerFunction
|
|
<< " average variables per function.\n"
|
|
<< " " << MaxUninitAnalysisVariablesPerFunction
|
|
<< " max variables per function.\n"
|
|
<< " " << NumUninitAnalysisBlockVisits << " block visits.\n"
|
|
<< " " << AvgUninitBlockVisitsPerFunction
|
|
<< " average block visits per function.\n"
|
|
<< " " << MaxUninitAnalysisBlockVisitsPerFunction
|
|
<< " max block visits per function.\n";
|
|
}
|