[memprof] Update YAML traits for writer purposes (#118720)
[llvm-project.git] / clang / lib / StaticAnalyzer / Checkers / UndefCapturedBlockVarChecker.cpp
blob2839ef0b6d2e610c6d2dc72aacca1c390f9186f7
1 // UndefCapturedBlockVarChecker.cpp - Uninitialized captured vars -*- C++ -*-=//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This checker detects blocks that capture uninitialized values.
11 //===----------------------------------------------------------------------===//
13 #include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
14 #include "clang/AST/Attr.h"
15 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
16 #include "clang/StaticAnalyzer/Core/Checker.h"
17 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
18 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
19 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
20 #include "llvm/ADT/SmallString.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include <optional>
24 using namespace clang;
25 using namespace ento;
27 namespace {
28 class UndefCapturedBlockVarChecker
29 : public Checker< check::PostStmt<BlockExpr> > {
30 const BugType BT{this, "uninitialized variable captured by block"};
32 public:
33 void checkPostStmt(const BlockExpr *BE, CheckerContext &C) const;
35 } // end anonymous namespace
37 static const DeclRefExpr *FindBlockDeclRefExpr(const Stmt *S,
38 const VarDecl *VD) {
39 if (const DeclRefExpr *BR = dyn_cast<DeclRefExpr>(S))
40 if (BR->getDecl() == VD)
41 return BR;
43 for (const Stmt *Child : S->children())
44 if (Child)
45 if (const DeclRefExpr *BR = FindBlockDeclRefExpr(Child, VD))
46 return BR;
48 return nullptr;
51 void
52 UndefCapturedBlockVarChecker::checkPostStmt(const BlockExpr *BE,
53 CheckerContext &C) const {
54 if (!BE->getBlockDecl()->hasCaptures())
55 return;
57 ProgramStateRef state = C.getState();
58 auto *R = cast<BlockDataRegion>(C.getSVal(BE).getAsRegion());
60 for (auto Var : R->referenced_vars()) {
61 // This VarRegion is the region associated with the block; we need
62 // the one associated with the encompassing context.
63 const VarRegion *VR = Var.getCapturedRegion();
64 const VarDecl *VD = VR->getDecl();
66 if (VD->hasAttr<BlocksAttr>() || !VD->hasLocalStorage())
67 continue;
69 // Get the VarRegion associated with VD in the local stack frame.
70 if (std::optional<UndefinedVal> V =
71 state->getSVal(Var.getOriginalRegion()).getAs<UndefinedVal>()) {
72 if (ExplodedNode *N = C.generateErrorNode()) {
73 // Generate a bug report.
74 SmallString<128> buf;
75 llvm::raw_svector_ostream os(buf);
77 os << "Variable '" << VD->getName()
78 << "' is uninitialized when captured by block";
80 auto R = std::make_unique<PathSensitiveBugReport>(BT, os.str(), N);
81 if (const Expr *Ex = FindBlockDeclRefExpr(BE->getBody(), VD))
82 R->addRange(Ex->getSourceRange());
83 bugreporter::trackStoredValue(*V, VR, *R,
84 {bugreporter::TrackingKind::Thorough,
85 /*EnableNullFPSuppression*/ false});
86 R->disablePathPruning();
87 // need location of block
88 C.emitReport(std::move(R));
94 void ento::registerUndefCapturedBlockVarChecker(CheckerManager &mgr) {
95 mgr.registerChecker<UndefCapturedBlockVarChecker>();
98 bool ento::shouldRegisterUndefCapturedBlockVarChecker(const CheckerManager &mgr) {
99 return true;