1837 lines
65 KiB
C++
1837 lines
65 KiB
C++
//=- AnalysisBasedWarnings.cpp - Sema warnings based on libAnalysis -*- C++ -*-=//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file defines analysis_warnings::[Policy,Executor].
|
|
// Together they are used by Sema to issue warnings based on inexpensive
|
|
// static analysis algorithms in libAnalysis.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "clang/Sema/AnalysisBasedWarnings.h"
|
|
#include "clang/AST/DeclCXX.h"
|
|
#include "clang/AST/DeclObjC.h"
|
|
#include "clang/AST/EvaluatedExprVisitor.h"
|
|
#include "clang/AST/ExprCXX.h"
|
|
#include "clang/AST/ExprObjC.h"
|
|
#include "clang/AST/ParentMap.h"
|
|
#include "clang/AST/RecursiveASTVisitor.h"
|
|
#include "clang/AST/StmtCXX.h"
|
|
#include "clang/AST/StmtObjC.h"
|
|
#include "clang/AST/StmtVisitor.h"
|
|
#include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
|
|
#include "clang/Analysis/Analyses/Consumed.h"
|
|
#include "clang/Analysis/Analyses/ReachableCode.h"
|
|
#include "clang/Analysis/Analyses/ThreadSafety.h"
|
|
#include "clang/Analysis/Analyses/UninitializedValues.h"
|
|
#include "clang/Analysis/AnalysisContext.h"
|
|
#include "clang/Analysis/CFG.h"
|
|
#include "clang/Analysis/CFGStmtMap.h"
|
|
#include "clang/Basic/SourceLocation.h"
|
|
#include "clang/Basic/SourceManager.h"
|
|
#include "clang/Lex/Lexer.h"
|
|
#include "clang/Lex/Preprocessor.h"
|
|
#include "clang/Sema/ScopeInfo.h"
|
|
#include "clang/Sema/SemaInternal.h"
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/ADT/BitVector.h"
|
|
#include "llvm/ADT/FoldingSet.h"
|
|
#include "llvm/ADT/ImmutableMap.h"
|
|
#include "llvm/ADT/MapVector.h"
|
|
#include "llvm/ADT/PostOrderIterator.h"
|
|
#include "llvm/ADT/SmallString.h"
|
|
#include "llvm/ADT/SmallVector.h"
|
|
#include "llvm/ADT/StringRef.h"
|
|
#include "llvm/Support/Casting.h"
|
|
#include <algorithm>
|
|
#include <deque>
|
|
#include <iterator>
|
|
#include <vector>
|
|
|
|
using namespace clang;
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Unreachable code analysis.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
class UnreachableCodeHandler : public reachable_code::Callback {
|
|
Sema &S;
|
|
public:
|
|
UnreachableCodeHandler(Sema &s) : S(s) {}
|
|
|
|
void HandleUnreachable(SourceLocation L, SourceRange R1, SourceRange R2) {
|
|
S.Diag(L, diag::warn_unreachable) << R1 << R2;
|
|
}
|
|
};
|
|
}
|
|
|
|
/// CheckUnreachable - Check for unreachable code.
|
|
static void CheckUnreachable(Sema &S, AnalysisDeclContext &AC) {
|
|
UnreachableCodeHandler UC(S);
|
|
reachable_code::FindUnreachableCode(AC, UC);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Check for missing return value.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
enum ControlFlowKind {
|
|
UnknownFallThrough,
|
|
NeverFallThrough,
|
|
MaybeFallThrough,
|
|
AlwaysFallThrough,
|
|
NeverFallThroughOrReturn
|
|
};
|
|
|
|
/// CheckFallThrough - Check that we don't fall off the end of a
|
|
/// Statement that should return a value.
|
|
///
|
|
/// \returns AlwaysFallThrough iff we always fall off the end of the statement,
|
|
/// MaybeFallThrough iff we might or might not fall off the end,
|
|
/// NeverFallThroughOrReturn iff we never fall off the end of the statement or
|
|
/// return. We assume NeverFallThrough iff we never fall off the end of the
|
|
/// statement but we may return. We assume that functions not marked noreturn
|
|
/// will return.
|
|
static ControlFlowKind CheckFallThrough(AnalysisDeclContext &AC) {
|
|
CFG *cfg = AC.getCFG();
|
|
if (cfg == 0) return UnknownFallThrough;
|
|
|
|
// The CFG leaves in dead things, and we don't want the dead code paths to
|
|
// confuse us, so we mark all live things first.
|
|
llvm::BitVector live(cfg->getNumBlockIDs());
|
|
unsigned count = reachable_code::ScanReachableFromBlock(&cfg->getEntry(),
|
|
live);
|
|
|
|
bool AddEHEdges = AC.getAddEHEdges();
|
|
if (!AddEHEdges && count != cfg->getNumBlockIDs())
|
|
// When there are things remaining dead, and we didn't add EH edges
|
|
// from CallExprs to the catch clauses, we have to go back and
|
|
// mark them as live.
|
|
for (CFG::iterator I = cfg->begin(), E = cfg->end(); I != E; ++I) {
|
|
CFGBlock &b = **I;
|
|
if (!live[b.getBlockID()]) {
|
|
if (b.pred_begin() == b.pred_end()) {
|
|
if (b.getTerminator() && isa<CXXTryStmt>(b.getTerminator()))
|
|
// When not adding EH edges from calls, catch clauses
|
|
// can otherwise seem dead. Avoid noting them as dead.
|
|
count += reachable_code::ScanReachableFromBlock(&b, live);
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Now we know what is live, we check the live precessors of the exit block
|
|
// and look for fall through paths, being careful to ignore normal returns,
|
|
// and exceptional paths.
|
|
bool HasLiveReturn = false;
|
|
bool HasFakeEdge = false;
|
|
bool HasPlainEdge = false;
|
|
bool HasAbnormalEdge = false;
|
|
|
|
// Ignore default cases that aren't likely to be reachable because all
|
|
// enums in a switch(X) have explicit case statements.
|
|
CFGBlock::FilterOptions FO;
|
|
FO.IgnoreDefaultsWithCoveredEnums = 1;
|
|
|
|
for (CFGBlock::filtered_pred_iterator
|
|
I = cfg->getExit().filtered_pred_start_end(FO); I.hasMore(); ++I) {
|
|
const CFGBlock& B = **I;
|
|
if (!live[B.getBlockID()])
|
|
continue;
|
|
|
|
// 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).
|
|
CFGBlock::const_reverse_iterator ri = B.rbegin(), re = B.rend();
|
|
|
|
for ( ; ri != re ; ++ri)
|
|
if (ri->getAs<CFGStmt>())
|
|
break;
|
|
|
|
// No more CFGElements in the block?
|
|
if (ri == re) {
|
|
if (B.getTerminator() && isa<CXXTryStmt>(B.getTerminator())) {
|
|
HasAbnormalEdge = true;
|
|
continue;
|
|
}
|
|
// A labeled empty statement, or the entry block...
|
|
HasPlainEdge = true;
|
|
continue;
|
|
}
|
|
|
|
CFGStmt CS = ri->castAs<CFGStmt>();
|
|
const Stmt *S = CS.getStmt();
|
|
if (isa<ReturnStmt>(S)) {
|
|
HasLiveReturn = true;
|
|
continue;
|
|
}
|
|
if (isa<ObjCAtThrowStmt>(S)) {
|
|
HasFakeEdge = true;
|
|
continue;
|
|
}
|
|
if (isa<CXXThrowExpr>(S)) {
|
|
HasFakeEdge = true;
|
|
continue;
|
|
}
|
|
if (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 } 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 MakeForBlock() {
|
|
CheckFallThroughDiagnostics D;
|
|
D.diag_MaybeFallThrough_HasNoReturn =
|
|
diag::err_noreturn_block_has_return_expr;
|
|
D.diag_MaybeFallThrough_ReturnsNonVoid =
|
|
diag::err_maybe_falloff_nonvoid_block;
|
|
D.diag_AlwaysFallThrough_HasNoReturn =
|
|
diag::err_noreturn_block_has_return_expr;
|
|
D.diag_AlwaysFallThrough_ReturnsNonVoid =
|
|
diag::err_falloff_nonvoid_block;
|
|
D.diag_NeverFallThroughOrReturn =
|
|
diag::warn_suggest_noreturn_block;
|
|
D.funMode = 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.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function,
|
|
FuncLoc) == DiagnosticsEngine::Ignored)
|
|
&& (!HasNoReturn ||
|
|
D.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr,
|
|
FuncLoc) == DiagnosticsEngine::Ignored)
|
|
&& (!ReturnsVoid ||
|
|
D.getDiagnosticLevel(diag::warn_suggest_noreturn_block, FuncLoc)
|
|
== DiagnosticsEngine::Ignored);
|
|
}
|
|
|
|
// For blocks / lambdas.
|
|
return ReturnsVoid && !HasNoReturn
|
|
&& ((funMode == Lambda) ||
|
|
D.getDiagnosticLevel(diag::warn_suggest_noreturn_block, FuncLoc)
|
|
== DiagnosticsEngine::Ignored);
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a
|
|
/// function that should return a value. Check that we don't fall off the end
|
|
/// of a noreturn function. We assume that functions and blocks not marked
|
|
/// noreturn will return.
|
|
static void CheckFallThroughForBody(Sema &S, const Decl *D, const Stmt *Body,
|
|
const BlockExpr *blkExpr,
|
|
const CheckFallThroughDiagnostics& CD,
|
|
AnalysisDeclContext &AC) {
|
|
|
|
bool ReturnsVoid = false;
|
|
bool HasNoReturn = false;
|
|
|
|
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
|
|
ReturnsVoid = FD->getResultType()->isVoidType();
|
|
HasNoReturn = FD->isNoReturn();
|
|
}
|
|
else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
|
|
ReturnsVoid = MD->getResultType()->isVoidType();
|
|
HasNoReturn = MD->hasAttr<NoReturnAttr>();
|
|
}
|
|
else if (isa<BlockDecl>(D)) {
|
|
QualType BlockTy = blkExpr->getType();
|
|
if (const FunctionType *FT =
|
|
BlockTy->getPointeeType()->getAs<FunctionType>()) {
|
|
if (FT->getResultType()->isVoidType())
|
|
ReturnsVoid = true;
|
|
if (FT->getNoReturnAttr())
|
|
HasNoReturn = true;
|
|
}
|
|
}
|
|
|
|
DiagnosticsEngine &Diags = S.getDiagnostics();
|
|
|
|
// Short circuit for compilation speed.
|
|
if (CD.checkDiagnostics(Diags, ReturnsVoid, HasNoReturn))
|
|
return;
|
|
|
|
// FIXME: Function try block
|
|
if (const CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) {
|
|
switch (CheckFallThrough(AC)) {
|
|
case UnknownFallThrough:
|
|
break;
|
|
|
|
case MaybeFallThrough:
|
|
if (HasNoReturn)
|
|
S.Diag(Compound->getRBracLoc(),
|
|
CD.diag_MaybeFallThrough_HasNoReturn);
|
|
else if (!ReturnsVoid)
|
|
S.Diag(Compound->getRBracLoc(),
|
|
CD.diag_MaybeFallThrough_ReturnsNonVoid);
|
|
break;
|
|
case AlwaysFallThrough:
|
|
if (HasNoReturn)
|
|
S.Diag(Compound->getRBracLoc(),
|
|
CD.diag_AlwaysFallThrough_HasNoReturn);
|
|
else if (!ReturnsVoid)
|
|
S.Diag(Compound->getRBracLoc(),
|
|
CD.diag_AlwaysFallThrough_ReturnsNonVoid);
|
|
break;
|
|
case NeverFallThroughOrReturn:
|
|
if (ReturnsVoid && !HasNoReturn && CD.diag_NeverFallThroughOrReturn) {
|
|
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
|
|
S.Diag(Compound->getLBracLoc(), CD.diag_NeverFallThroughOrReturn)
|
|
<< 0 << FD;
|
|
} else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
|
|
S.Diag(Compound->getLBracLoc(), CD.diag_NeverFallThroughOrReturn)
|
|
<< 1 << MD;
|
|
} else {
|
|
S.Diag(Compound->getLBracLoc(), CD.diag_NeverFallThroughOrReturn);
|
|
}
|
|
}
|
|
break;
|
|
case NeverFallThrough:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// -Wuninitialized
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
/// ContainsReference - A visitor class to search for references to
|
|
/// a particular declaration (the needle) within any evaluated component of an
|
|
/// expression (recursively).
|
|
class ContainsReference : public EvaluatedExprVisitor<ContainsReference> {
|
|
bool FoundReference;
|
|
const DeclRefExpr *Needle;
|
|
|
|
public:
|
|
ContainsReference(ASTContext &Context, const DeclRefExpr *Needle)
|
|
: EvaluatedExprVisitor<ContainsReference>(Context),
|
|
FoundReference(false), Needle(Needle) {}
|
|
|
|
void VisitExpr(Expr *E) {
|
|
// Stop evaluating if we already have a reference.
|
|
if (FoundReference)
|
|
return;
|
|
|
|
EvaluatedExprVisitor<ContainsReference>::VisitExpr(E);
|
|
}
|
|
|
|
void VisitDeclRefExpr(DeclRefExpr *E) {
|
|
if (E == Needle)
|
|
FoundReference = true;
|
|
else
|
|
EvaluatedExprVisitor<ContainsReference>::VisitDeclRefExpr(E);
|
|
}
|
|
|
|
bool doesContainReference() const { return FoundReference; }
|
|
};
|
|
}
|
|
|
|
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->getLocEnd().isMacroID())
|
|
return false;
|
|
|
|
SourceLocation Loc = S.PP.getLocForEndOfToken(VD->getLocEnd());
|
|
|
|
// 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->getLocStart(),
|
|
Then->getLocStart()));
|
|
if (Else) {
|
|
SourceLocation ElseKwLoc = Lexer::getLocForEndOfToken(
|
|
Then->getLocEnd(), 0, S.getSourceManager(), S.getLangOpts());
|
|
Fixit2 = FixItHint::CreateRemoval(
|
|
SourceRange(ElseKwLoc, Else->getLocEnd()));
|
|
}
|
|
} else {
|
|
// If condition is always false, remove all but the 'else'.
|
|
if (Else)
|
|
Fixit1 = FixItHint::CreateRemoval(
|
|
CharSourceRange::getCharRange(If->getLocStart(),
|
|
Else->getLocStart()));
|
|
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()->getLocStart(), 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()->getLocStart(), 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->getLocStart(),
|
|
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->getLocStart(), 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()->getLocStart(), diag::warn_maybe_uninit_var)
|
|
<< VD->getDeclName() << IsCapturedByBlock
|
|
<< Use.getUser()->getSourceRange();
|
|
}
|
|
|
|
/// 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(const_cast<Expr*>(Initializer));
|
|
if (CR.doesContainReference()) {
|
|
S.Diag(DRE->getLocStart(),
|
|
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->getLocStart(),
|
|
diag::warn_uninit_byref_blockvar_captured_by_block)
|
|
<< VD->getDeclName();
|
|
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->getLocStart(), diag::note_uninit_var_def)
|
|
<< 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 (CFG::iterator I = Cfg->begin(), E = Cfg->end(); I != E; ++I) {
|
|
const CFGBlock *B = *I;
|
|
const Stmt *L = B->getLabel();
|
|
if (L && isa<SwitchCase>(L) && ReachableBlocks.insert(B))
|
|
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))
|
|
BlockQueue.push_back(*I);
|
|
}
|
|
}
|
|
}
|
|
|
|
bool checkFallThroughIntoBlock(const CFGBlock &B, int &AnnotatedCnt) {
|
|
assert(!ReachableBlocks.empty() && "ReachableBlocks empty");
|
|
|
|
int UnannotatedCnt = 0;
|
|
AnnotatedCnt = 0;
|
|
|
|
std::deque<const CFGBlock*> BlockQueue;
|
|
|
|
std::copy(B.pred_begin(), B.pred_end(), std::back_inserter(BlockQueue));
|
|
|
|
while (!BlockQueue.empty()) {
|
|
const CFGBlock *P = BlockQueue.front();
|
|
BlockQueue.pop_front();
|
|
|
|
const Stmt *Term = P->getTerminator();
|
|
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())) {
|
|
S.Diag(AS->getLocStart(),
|
|
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; }
|
|
|
|
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 0;
|
|
}
|
|
|
|
static const Stmt *getLastStmt(const CFGBlock &B) {
|
|
if (const Stmt *Term = B.getTerminator())
|
|
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 0;
|
|
}
|
|
|
|
bool FoundSwitchStatements;
|
|
AttrStmts FallthroughStmts;
|
|
Sema &S;
|
|
llvm::SmallPtrSet<const CFGBlock *, 16> ReachableBlocks;
|
|
};
|
|
}
|
|
|
|
static void DiagnoseSwitchLabelsFallthrough(Sema &S, AnalysisDeclContext &AC,
|
|
bool PerFunction) {
|
|
// Only perform this analysis when using C++11. There is no good workflow
|
|
// for this warning when not using C++11. There is no good way to silence
|
|
// the warning (no attribute is available) unless we are using C++11's support
|
|
// for generalized attributes. Once could use pragmas to silence the warning,
|
|
// but as a general solution that is gross and not in the spirit of this
|
|
// warning.
|
|
//
|
|
// NOTE: This an intermediate solution. There are on-going discussions on
|
|
// how to properly support this warning outside of C++11 with an annotation.
|
|
if (!AC.getASTContext().getLangOpts().CPlusPlus11)
|
|
return;
|
|
|
|
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 (CFG::reverse_iterator I = Cfg->rbegin(), E = Cfg->rend(); I != E; ++I) {
|
|
const CFGBlock *B = *I;
|
|
const Stmt *Label = B->getLabel();
|
|
|
|
if (!Label || !isa<SwitchCase>(Label))
|
|
continue;
|
|
|
|
int AnnotatedCnt;
|
|
|
|
if (!FM.checkFallThroughIntoBlock(*B, AnnotatedCnt))
|
|
continue;
|
|
|
|
S.Diag(Label->getLocStart(),
|
|
PerFunction ? diag::warn_unannotated_fallthrough_per_function
|
|
: diag::warn_unannotated_fallthrough);
|
|
|
|
if (!AnnotatedCnt) {
|
|
SourceLocation L = Label->getLocStart();
|
|
if (L.isMacroID())
|
|
continue;
|
|
if (S.getLangOpts().CPlusPlus11) {
|
|
const Stmt *Term = B->getTerminator();
|
|
// Skip empty cases.
|
|
while (B->empty() && !Term && B->succ_size() == 1) {
|
|
B = *B->succ_begin();
|
|
Term = B->getTerminator();
|
|
}
|
|
if (!(B->empty() && Term && isa<BreakStmt>(Term))) {
|
|
Preprocessor &PP = S.getPreprocessor();
|
|
TokenValue Tokens[] = {
|
|
tok::l_square, tok::l_square, PP.getIdentifierInfo("clang"),
|
|
tok::coloncolon, PP.getIdentifierInfo("fallthrough"),
|
|
tok::r_square, tok::r_square
|
|
};
|
|
StringRef AnnotationSpelling = "[[clang::fallthrough]]";
|
|
StringRef MacroName = PP.getLastMacroWithSpelling(L, Tokens);
|
|
if (!MacroName.empty())
|
|
AnnotationSpelling = MacroName;
|
|
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; ");
|
|
}
|
|
}
|
|
|
|
const FallthroughMapper::AttrStmts &Fallthroughs = FM.getFallthroughStmts();
|
|
for (FallthroughMapper::AttrStmts::const_iterator I = Fallthroughs.begin(),
|
|
E = Fallthroughs.end();
|
|
I != E; ++I) {
|
|
S.Diag((*I)->getLocStart(), diag::warn_fallthrough_attr_invalid_placement);
|
|
}
|
|
|
|
}
|
|
|
|
namespace {
|
|
typedef std::pair<const Stmt *,
|
|
sema::FunctionScopeInfo::WeakObjectUseMap::const_iterator>
|
|
StmtUsesPair;
|
|
|
|
class StmtUseSorter {
|
|
const SourceManager &SM;
|
|
|
|
public:
|
|
explicit StmtUseSorter(const SourceManager &SM) : SM(SM) { }
|
|
|
|
bool operator()(const StmtUsesPair &LHS, const StmtUsesPair &RHS) {
|
|
return SM.isBeforeInTranslationUnit(LHS.first->getLocStart(),
|
|
RHS.first->getLocStart());
|
|
}
|
|
};
|
|
}
|
|
|
|
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: {
|
|
const Expr *Cond = cast<DoStmt>(S)->getCond();
|
|
llvm::APSInt Val;
|
|
if (!Cond->EvaluateAsInt(Val, Ctx))
|
|
return true;
|
|
return Val.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;
|
|
|
|
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.
|
|
std::sort(UsesByStmt.begin(), UsesByStmt.end(),
|
|
StmtUseSorter(S.getSourceManager()));
|
|
|
|
// 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 (SmallVectorImpl<StmtUsesPair>::const_iterator I = UsesByStmt.begin(),
|
|
E = UsesByStmt.end();
|
|
I != E; ++I) {
|
|
const Stmt *FirstRead = I->first;
|
|
const WeakObjectProfileTy &Key = I->second->first;
|
|
const WeakUseVector &Uses = I->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 *D = Key.getProperty();
|
|
if (isa<VarDecl>(D))
|
|
ObjectKind = Variable;
|
|
else if (isa<ObjCPropertyDecl>(D))
|
|
ObjectKind = Property;
|
|
else if (isa<ObjCMethodDecl>(D))
|
|
ObjectKind = ImplicitProperty;
|
|
else if (isa<ObjCIvarDecl>(D))
|
|
ObjectKind = Ivar;
|
|
else
|
|
llvm_unreachable("Unexpected weak object kind!");
|
|
|
|
// Show the first time the object was read.
|
|
S.Diag(FirstRead->getLocStart(), DiagKind)
|
|
<< int(ObjectKind) << D << int(FunctionKind)
|
|
<< FirstRead->getSourceRange();
|
|
|
|
// Print all the other accesses as notes.
|
|
for (WeakUseVector::const_iterator UI = Uses.begin(), UE = Uses.end();
|
|
UI != UE; ++UI) {
|
|
if (UI->getUseExpr() == FirstRead)
|
|
continue;
|
|
S.Diag(UI->getUseExpr()->getLocStart(),
|
|
diag::note_arc_weak_also_accessed_here)
|
|
<< UI->getUseExpr()->getSourceRange();
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
namespace {
|
|
struct SLocSort {
|
|
bool operator()(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();
|
|
SourceLocation aLoc = a.getUser()->getLocStart();
|
|
SourceLocation bLoc = b.getUser()->getLocStart();
|
|
return aLoc.getRawEncoding() < bLoc.getRawEncoding();
|
|
}
|
|
};
|
|
|
|
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;
|
|
|
|
public:
|
|
UninitValsDiagReporter(Sema &S) : S(S), uses(0) {}
|
|
~UninitValsDiagReporter() {
|
|
flushDiagnostics();
|
|
}
|
|
|
|
MappedType &getUses(const VarDecl *vd) {
|
|
if (!uses)
|
|
uses = new UsesMap();
|
|
|
|
MappedType &V = (*uses)[vd];
|
|
if (!V.getPointer())
|
|
V.setPointer(new UsesVec());
|
|
|
|
return V;
|
|
}
|
|
|
|
void handleUseOfUninitVariable(const VarDecl *vd, const UninitUse &use) {
|
|
getUses(vd).getPointer()->push_back(use);
|
|
}
|
|
|
|
void handleSelfInit(const VarDecl *vd) {
|
|
getUses(vd).setInt(true);
|
|
}
|
|
|
|
void flushDiagnostics() {
|
|
if (!uses)
|
|
return;
|
|
|
|
for (UsesMap::iterator i = uses->begin(), e = uses->end(); i != e; ++i) {
|
|
const VarDecl *vd = i->first;
|
|
const MappedType &V = i->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.
|
|
std::sort(vec->begin(), vec->end(), SLocSort());
|
|
|
|
for (UsesVec::iterator vi = vec->begin(), ve = vec->end(); vi != ve;
|
|
++vi) {
|
|
// If we have self-init, downgrade all uses to 'may be uninitialized'.
|
|
UninitUse Use = hasSelfInit ? UninitUse(vi->getUser(), false) : *vi;
|
|
|
|
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;
|
|
}
|
|
delete uses;
|
|
}
|
|
|
|
private:
|
|
static bool hasAlwaysUninitializedUse(const UsesVec* vec) {
|
|
for (UsesVec::const_iterator i = vec->begin(), e = vec->end(); i != e; ++i) {
|
|
if (i->getKind() == UninitUse::Always ||
|
|
i->getKind() == UninitUse::AfterCall ||
|
|
i->getKind() == UninitUse::AfterDecl) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
};
|
|
}
|
|
|
|
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);
|
|
}
|
|
};
|
|
}}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// -Wthread-safety
|
|
//===----------------------------------------------------------------------===//
|
|
namespace clang {
|
|
namespace thread_safety {
|
|
namespace {
|
|
class ThreadSafetyReporter : public clang::thread_safety::ThreadSafetyHandler {
|
|
Sema &S;
|
|
DiagList Warnings;
|
|
SourceLocation FunLocation, FunEndLocation;
|
|
|
|
// Helper functions
|
|
void warnLockMismatch(unsigned DiagID, Name LockName, SourceLocation Loc) {
|
|
// Gracefully handle rare cases when the analysis can't get a more
|
|
// precise source location.
|
|
if (!Loc.isValid())
|
|
Loc = FunLocation;
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << LockName);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
public:
|
|
ThreadSafetyReporter(Sema &S, SourceLocation FL, SourceLocation FEL)
|
|
: S(S), FunLocation(FL), FunEndLocation(FEL) {}
|
|
|
|
/// \brief 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 (DiagList::iterator I = Warnings.begin(), E = Warnings.end();
|
|
I != E; ++I) {
|
|
S.Diag(I->first.first, I->first.second);
|
|
const OptionalNotes &Notes = I->second;
|
|
for (unsigned NoteI = 0, NoteN = Notes.size(); NoteI != NoteN; ++NoteI)
|
|
S.Diag(Notes[NoteI].first, Notes[NoteI].second);
|
|
}
|
|
}
|
|
|
|
void handleInvalidLockExp(SourceLocation Loc) {
|
|
PartialDiagnosticAt Warning(Loc,
|
|
S.PDiag(diag::warn_cannot_resolve_lock) << Loc);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
void handleUnmatchedUnlock(Name LockName, SourceLocation Loc) {
|
|
warnLockMismatch(diag::warn_unlock_but_no_lock, LockName, Loc);
|
|
}
|
|
|
|
void handleDoubleLock(Name LockName, SourceLocation Loc) {
|
|
warnLockMismatch(diag::warn_double_lock, LockName, Loc);
|
|
}
|
|
|
|
void handleMutexHeldEndOfScope(Name LockName, SourceLocation LocLocked,
|
|
SourceLocation LocEndOfScope,
|
|
LockErrorKind LEK){
|
|
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) << LockName);
|
|
if (LocLocked.isValid()) {
|
|
PartialDiagnosticAt Note(LocLocked, S.PDiag(diag::note_locked_here));
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes(1, Note)));
|
|
return;
|
|
}
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
|
|
void handleExclusiveAndShared(Name LockName, SourceLocation Loc1,
|
|
SourceLocation Loc2) {
|
|
PartialDiagnosticAt Warning(
|
|
Loc1, S.PDiag(diag::warn_lock_exclusive_and_shared) << LockName);
|
|
PartialDiagnosticAt Note(
|
|
Loc2, S.PDiag(diag::note_lock_exclusive_and_shared) << LockName);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes(1, Note)));
|
|
}
|
|
|
|
void handleNoMutexHeld(const NamedDecl *D, ProtectedOperationKind POK,
|
|
AccessKind AK, SourceLocation Loc) {
|
|
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->getNameAsString() << getLockKindFromAccessKind(AK));
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void handleMutexNotHeld(const NamedDecl *D, ProtectedOperationKind POK,
|
|
Name LockName, LockKind LK, SourceLocation Loc,
|
|
Name *PossibleMatch) {
|
|
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;
|
|
}
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID)
|
|
<< D->getNameAsString() << LockName << LK);
|
|
PartialDiagnosticAt Note(Loc, S.PDiag(diag::note_found_mutex_near_match)
|
|
<< *PossibleMatch);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes(1, 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;
|
|
}
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID)
|
|
<< D->getNameAsString() << LockName << LK);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
}
|
|
|
|
void handleFunExcludesLock(Name FunName, Name LockName, SourceLocation Loc) {
|
|
PartialDiagnosticAt Warning(Loc,
|
|
S.PDiag(diag::warn_fun_excludes_mutex) << FunName << LockName);
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
};
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// -Wconsumed
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace clang {
|
|
namespace consumed {
|
|
namespace {
|
|
class ConsumedWarningsHandler : public ConsumedWarningsHandlerBase {
|
|
|
|
Sema &S;
|
|
DiagList Warnings;
|
|
|
|
public:
|
|
|
|
ConsumedWarningsHandler(Sema &S) : S(S) {}
|
|
|
|
void emitDiagnostics() {
|
|
Warnings.sort(SortDiagBySourceLocation(S.getSourceManager()));
|
|
|
|
for (DiagList::iterator I = Warnings.begin(), E = Warnings.end();
|
|
I != E; ++I) {
|
|
|
|
const OptionalNotes &Notes = I->second;
|
|
S.Diag(I->first.first, I->first.second);
|
|
|
|
for (unsigned NoteI = 0, NoteN = Notes.size(); NoteI != NoteN; ++NoteI) {
|
|
S.Diag(Notes[NoteI].first, Notes[NoteI].second);
|
|
}
|
|
}
|
|
}
|
|
|
|
void warnLoopStateMismatch(SourceLocation Loc, StringRef VariableName) {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_loop_state_mismatch) <<
|
|
VariableName);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnParamReturnTypestateMismatch(SourceLocation Loc,
|
|
StringRef VariableName,
|
|
StringRef ExpectedState,
|
|
StringRef ObservedState) {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_param_return_typestate_mismatch) << VariableName <<
|
|
ExpectedState << ObservedState);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnParamTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
|
|
StringRef ObservedState) {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_param_typestate_mismatch) << ExpectedState << ObservedState);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnReturnTypestateForUnconsumableType(SourceLocation Loc,
|
|
StringRef TypeName) {
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_return_typestate_for_unconsumable_type) << TypeName);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnReturnTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
|
|
StringRef ObservedState) {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_return_typestate_mismatch) << ExpectedState << ObservedState);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnUseOfTempInInvalidState(StringRef MethodName, StringRef State,
|
|
SourceLocation Loc) {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(
|
|
diag::warn_use_of_temp_in_invalid_state) << MethodName << State);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
|
|
void warnUseInInvalidState(StringRef MethodName, StringRef VariableName,
|
|
StringRef State, SourceLocation Loc) {
|
|
|
|
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_use_in_invalid_state) <<
|
|
MethodName << VariableName << State);
|
|
|
|
Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
|
|
}
|
|
};
|
|
}}}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// 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;
|
|
}
|
|
|
|
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) {
|
|
DiagnosticsEngine &D = S.getDiagnostics();
|
|
DefaultPolicy.enableCheckUnreachable = (unsigned)
|
|
(D.getDiagnosticLevel(diag::warn_unreachable, SourceLocation()) !=
|
|
DiagnosticsEngine::Ignored);
|
|
DefaultPolicy.enableThreadSafetyAnalysis = (unsigned)
|
|
(D.getDiagnosticLevel(diag::warn_double_lock, SourceLocation()) !=
|
|
DiagnosticsEngine::Ignored);
|
|
DefaultPolicy.enableConsumedAnalysis = (unsigned)
|
|
(D.getDiagnosticLevel(diag::warn_use_in_invalid_state, SourceLocation()) !=
|
|
DiagnosticsEngine::Ignored);
|
|
}
|
|
|
|
static void flushDiagnostics(Sema &S, sema::FunctionScopeInfo *fscope) {
|
|
for (SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
|
|
i = fscope->PossiblyUnreachableDiags.begin(),
|
|
e = fscope->PossiblyUnreachableDiags.end();
|
|
i != e; ++i) {
|
|
const sema::PossiblyUnreachableDiag &D = *i;
|
|
S.Diag(D.Loc, D.PD);
|
|
}
|
|
}
|
|
|
|
void clang::sema::
|
|
AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
|
|
sema::FunctionScopeInfo *fscope,
|
|
const Decl *D, const BlockExpr *blkExpr) {
|
|
|
|
// We avoid doing analysis-based warnings when there are errors for
|
|
// two reasons:
|
|
// (1) The CFGs often can't be constructed (if the body is invalid), so
|
|
// don't bother trying.
|
|
// (2) The code already has problems; running the analysis just takes more
|
|
// time.
|
|
DiagnosticsEngine &Diags = S.getDiagnostics();
|
|
|
|
// Do not do any analysis for declarations in system headers if we are
|
|
// going to just ignore them.
|
|
if (Diags.getSuppressSystemWarnings() &&
|
|
S.SourceMgr.isInSystemHeader(D->getLocation()))
|
|
return;
|
|
|
|
// For code in dependent contexts, we'll do this at instantiation time.
|
|
if (cast<DeclContext>(D)->isDependentContext())
|
|
return;
|
|
|
|
if (Diags.hasUncompilableErrorOccurred() || Diags.hasFatalErrorOccurred()) {
|
|
// 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 */ 0, 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;
|
|
|
|
// 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);
|
|
}
|
|
|
|
|
|
// Emit delayed diagnostics.
|
|
if (!fscope->PossiblyUnreachableDiags.empty()) {
|
|
bool analyzed = false;
|
|
|
|
// Register the expressions with the CFGBuilder.
|
|
for (SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
|
|
i = fscope->PossiblyUnreachableDiags.begin(),
|
|
e = fscope->PossiblyUnreachableDiags.end();
|
|
i != e; ++i) {
|
|
if (const Stmt *stmt = i->stmt)
|
|
AC.registerForcedBlockExpression(stmt);
|
|
}
|
|
|
|
if (AC.getCFG()) {
|
|
analyzed = true;
|
|
for (SmallVectorImpl<sema::PossiblyUnreachableDiag>::iterator
|
|
i = fscope->PossiblyUnreachableDiags.begin(),
|
|
e = fscope->PossiblyUnreachableDiags.end();
|
|
i != e; ++i)
|
|
{
|
|
const sema::PossiblyUnreachableDiag &D = *i;
|
|
bool processed = false;
|
|
if (const Stmt *stmt = i->stmt) {
|
|
const CFGBlock *block = AC.getBlockForRegisteredExpression(stmt);
|
|
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))
|
|
S.Diag(D.Loc, D.PD);
|
|
processed = true;
|
|
}
|
|
}
|
|
if (!processed) {
|
|
// Emit the warning anyway if we cannot map to a basic block.
|
|
S.Diag(D.Loc, D.PD);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!analyzed)
|
|
flushDiagnostics(S, fscope);
|
|
}
|
|
|
|
|
|
// Warning: check missing 'return'
|
|
if (P.enableCheckFallThrough) {
|
|
const CheckFallThroughDiagnostics &CD =
|
|
(isa<BlockDecl>(D) ? CheckFallThroughDiagnostics::MakeForBlock()
|
|
: (isa<CXXMethodDecl>(D) &&
|
|
cast<CXXMethodDecl>(D)->getOverloadedOperator() == OO_Call &&
|
|
cast<CXXMethodDecl>(D)->getParent()->isLambda())
|
|
? CheckFallThroughDiagnostics::MakeForLambda()
|
|
: CheckFallThroughDiagnostics::MakeForFunction(D));
|
|
CheckFallThroughForBody(S, D, Body, blkExpr, CD, AC);
|
|
}
|
|
|
|
// 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()->getLocEnd();
|
|
thread_safety::ThreadSafetyReporter Reporter(S, FL, FEL);
|
|
if (Diags.getDiagnosticLevel(diag::warn_thread_safety_beta,D->getLocStart())
|
|
!= DiagnosticsEngine::Ignored)
|
|
Reporter.setIssueBetaWarnings(true);
|
|
|
|
thread_safety::runThreadSafetyAnalysis(AC, Reporter);
|
|
Reporter.emitDiagnostics();
|
|
}
|
|
|
|
// Check for violations of consumed properties.
|
|
if (P.enableConsumedAnalysis) {
|
|
consumed::ConsumedWarningsHandler WarningHandler(S);
|
|
consumed::ConsumedAnalyzer Analyzer(WarningHandler);
|
|
Analyzer.run(AC);
|
|
}
|
|
|
|
if (Diags.getDiagnosticLevel(diag::warn_uninit_var, D->getLocStart())
|
|
!= DiagnosticsEngine::Ignored ||
|
|
Diags.getDiagnosticLevel(diag::warn_sometimes_uninit_var,D->getLocStart())
|
|
!= DiagnosticsEngine::Ignored ||
|
|
Diags.getDiagnosticLevel(diag::warn_maybe_uninit_var, D->getLocStart())
|
|
!= DiagnosticsEngine::Ignored) {
|
|
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.getDiagnosticLevel(diag::warn_unannotated_fallthrough,
|
|
D->getLocStart()) != DiagnosticsEngine::Ignored;
|
|
bool FallThroughDiagPerFunction =
|
|
Diags.getDiagnosticLevel(diag::warn_unannotated_fallthrough_per_function,
|
|
D->getLocStart()) != DiagnosticsEngine::Ignored;
|
|
if (FallThroughDiagFull || FallThroughDiagPerFunction) {
|
|
DiagnoseSwitchLabelsFallthrough(S, AC, !FallThroughDiagFull);
|
|
}
|
|
|
|
if (S.getLangOpts().ObjCARCWeak &&
|
|
Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak,
|
|
D->getLocStart()) != DiagnosticsEngine::Ignored)
|
|
diagnoseRepeatedUseOfWeak(S, fscope, D, AC.getParentMap());
|
|
|
|
// 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";
|
|
}
|