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// RUN: %clang_analyze_cc1 -std=c++14 \
// RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
// RUN: -analyzer-output=text -verify %s
#include "Inputs/llvm.h"
namespace clang {
struct Shape {
template <typename T>
const T *castAs() const;
template <typename T>
const T *getAs() const;
};
class Triangle : public Shape {};
class Rectangle : public Shape {};
class Hexagon : public Shape {};
class Circle : public Shape {};
} // namespace clang
using namespace llvm;
using namespace clang;
void evalReferences(const Shape &S) {
const auto &C = dyn_cast<Circle>(S);
// expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle &'}}
// expected-note@-2 {{Dereference of null pointer}}
// expected-warning@-3 {{Dereference of null pointer}}
}
void evalNonNullParamNonNullReturnReference(const Shape &S) {
const auto *C = dyn_cast_or_null<Circle>(S);
// expected-note@-1 {{'C' initialized here}}
if (!dyn_cast_or_null<Circle>(C)) {
// expected-note@-1 {{Assuming 'C' is a 'const class clang::Circle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Triangle>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Triangle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Rectangle>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Rectangle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Hexagon>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Hexagon *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle>(C)) {
// expected-note@-1 {{'C' is not a 'Triangle'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle, Rectangle>(C)) {
// expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle, Rectangle, Hexagon>(C)) {
// expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle' nor a 'Hexagon'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Circle, Rectangle, Hexagon>(C)) {
// expected-note@-1 {{'C' is a 'Circle'}}
// expected-note@-2 {{Taking true branch}}
(void)(1 / !C);
// expected-note@-1 {{'C' is non-null}}
// expected-note@-2 {{Division by zero}}
// expected-warning@-3 {{Division by zero}}
}
}
void evalNonNullParamNonNullReturn(const Shape *S) {
const auto *C = cast<Circle>(S);
// expected-note@-1 {{'S' is a 'const class clang::Circle *'}}
// expected-note@-2 {{'C' initialized here}}
if (!dyn_cast_or_null<Circle>(C)) {
// expected-note@-1 {{Assuming 'C' is a 'const class clang::Circle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Triangle>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Triangle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Rectangle>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Rectangle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (dyn_cast_or_null<Hexagon>(C)) {
// expected-note@-1 {{Assuming 'C' is not a 'const class clang::Hexagon *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle>(C)) {
// expected-note@-1 {{'C' is not a 'Triangle'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle, Rectangle>(C)) {
// expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Triangle, Rectangle, Hexagon>(C)) {
// expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle' nor a 'Hexagon'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (isa<Circle, Rectangle, Hexagon>(C)) {
// expected-note@-1 {{'C' is a 'Circle'}}
// expected-note@-2 {{Taking true branch}}
(void)(1 / !C);
// expected-note@-1 {{'C' is non-null}}
// expected-note@-2 {{Division by zero}}
// expected-warning@-3 {{Division by zero}}
}
}
void evalNonNullParamNullReturn(const Shape *S) {
const auto *C = dyn_cast_or_null<Circle>(S);
// expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle *'}}
if (const auto *T = dyn_cast_or_null<Triangle>(S)) {
// expected-note@-1 {{Assuming 'S' is a 'const class clang::Triangle *'}}
// expected-note@-2 {{'T' initialized here}}
// expected-note@-3 {{'T' is non-null}}
// expected-note@-4 {{Taking true branch}}
(void)(1 / !T);
// expected-note@-1 {{'T' is non-null}}
// expected-note@-2 {{Division by zero}}
// expected-warning@-3 {{Division by zero}}
}
}
void evalNullParamNullReturn(const Shape *S) {
const auto *C = dyn_cast_or_null<Circle>(S);
// expected-note@-1 {{Assuming null pointer is passed into cast}}
// expected-note@-2 {{'C' initialized to a null pointer value}}
(void)(1 / (bool)C);
// expected-note@-1 {{Division by zero}}
// expected-warning@-2 {{Division by zero}}
}
void evalZeroParamNonNullReturnPointer(const Shape *S) {
const auto *C = S->castAs<Circle>();
// expected-note@-1 {{'S' is a 'const class clang::Circle *'}}
// expected-note@-2 {{'C' initialized here}}
(void)(1 / !C);
// expected-note@-1 {{'C' is non-null}}
// expected-note@-2 {{Division by zero}}
// expected-warning@-3 {{Division by zero}}
}
void evalZeroParamNonNullReturn(const Shape &S) {
const auto *C = S.castAs<Circle>();
// expected-note@-1 {{'C' initialized here}}
(void)(1 / !C);
// expected-note@-1 {{'C' is non-null}}
// expected-note@-2 {{Division by zero}}
// expected-warning@-3 {{Division by zero}}
}
void evalZeroParamNullReturn(const Shape *S) {
const auto &C = S->getAs<Circle>();
// expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle *'}}
// expected-note@-2 {{Storing null pointer value}}
// expected-note@-3 {{'C' initialized here}}
if (!dyn_cast_or_null<Triangle>(S)) {
// expected-note@-1 {{Assuming 'S' is a 'const class clang::Triangle *'}}
// expected-note@-2 {{Taking false branch}}
return;
}
if (!dyn_cast_or_null<Triangle>(S)) {
// expected-note@-1 {{'S' is a 'Triangle'}}
// expected-note@-2 {{Taking false branch}}
return;
}
(void)(1 / (bool)C);
// expected-note@-1 {{Division by zero}}
// expected-warning@-2 {{Division by zero}}
}
// don't crash
// CastValueChecker was using QualType()->getPointeeCXXRecordDecl(), in
// getNoteTag which evaluated to nullptr, then crashed when attempting to
// deref an invocation to getNameAsString(). The fix is to use
// QualType().getAsString().
//
// Example:
// std::string CastToName =
// CastInfo ? CastInfo->to()->getAsCXXRecordDecl()->getNameAsString()
// : CastToTy->getPointeeCXXRecordDecl()->getNameAsString();
// Changed to:
// std::string CastToName =
// CastInfo ? CastInfo->to()->getAsCXXRecordDecl()->getNameAsString()
// : CastToTy.getAsString();
namespace llvm {
template <typename, typename a> void isa(a &);
template <typename> class PointerUnion {
public:
template <typename T> T *getAs() {
(void)isa<int>(*this);
return nullptr;
}
};
class LLVMContext {
PointerUnion<LLVMContext> c;
void d() { c.getAs<int>(); }
};
} // namespace llvm
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