llvm-project/clang/test/Analysis/pointer-to-member.cpp
Artem Dergachev 173f55693e [analyzer] pr38668: Do not attempt to cast loaded values of non-scalar types.
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.

Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store a float and load an integer, you won't have your float
rounded to an integer; instead, you will have garbage.

Admit that we cannot perform the cast as long as types we're dealing with are
non-trivial (neither integers, nor pointers).

Of course, if the cast is not necessary (eg, T1 == T2), we can still load the
value just fine.

Differential Revision: https://reviews.llvm.org/D55875

rdar://problem/45062567

llvm-svn: 349701
2018-12-19 23:48:44 +00:00

271 lines
6.9 KiB
C++

// RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify %s
void clang_analyzer_eval(bool);
struct A {
// This conversion operator allows implicit conversion to bool but not to other integer types.
typedef A * (A::*MemberPointer);
operator MemberPointer() const { return m_ptr ? &A::m_ptr : 0; }
A *m_ptr;
A *getPtr();
typedef A * (A::*MemberFnPointer)(void);
};
void testConditionalUse() {
A obj;
obj.m_ptr = &obj;
clang_analyzer_eval(obj.m_ptr); // expected-warning{{TRUE}}
clang_analyzer_eval(&A::m_ptr); // expected-warning{{TRUE}}
clang_analyzer_eval(obj); // expected-warning{{TRUE}}
obj.m_ptr = 0;
clang_analyzer_eval(obj.m_ptr); // expected-warning{{FALSE}}
clang_analyzer_eval(A::MemberPointer(0)); // expected-warning{{FALSE}}
clang_analyzer_eval(obj); // expected-warning{{FALSE}}
clang_analyzer_eval(&A::getPtr); // expected-warning{{TRUE}}
clang_analyzer_eval(A::MemberFnPointer(0)); // expected-warning{{FALSE}}
}
void testComparison() {
clang_analyzer_eval(&A::getPtr == &A::getPtr); // expected-warning{{TRUE}}
clang_analyzer_eval(&A::getPtr == 0); // expected-warning{{FALSE}}
clang_analyzer_eval(&A::m_ptr == &A::m_ptr); // expected-warning{{TRUE}}
}
namespace PR15742 {
template <class _T1, class _T2> struct A {
A (const _T1 &, const _T2 &);
};
typedef void *NPIdentifier;
template <class T> class B {
public:
typedef A<NPIdentifier, bool (T::*) (const NPIdentifier *, unsigned,
NPIdentifier *)> MethodMapMember;
};
class C : public B<C> {
public:
bool Find(const NPIdentifier *, unsigned, NPIdentifier *);
};
void InitStaticData () {
C::MethodMapMember(0, &C::Find); // don't crash
}
}
bool testDereferencing() {
A obj;
obj.m_ptr = 0;
A::MemberPointer member = &A::m_ptr;
clang_analyzer_eval(obj.*member == 0); // expected-warning{{TRUE}}
member = 0;
return obj.*member; // expected-warning{{The result of the '.*' expression is undefined}}
}
namespace testPointerToMemberFunction {
struct A {
virtual int foo() { return 1; }
int bar() { return 2; }
int static staticMemberFunction(int p) { return p + 1; };
};
struct B : public A {
virtual int foo() { return 3; }
};
typedef int (A::*AFnPointer)();
typedef int (B::*BFnPointer)();
void testPointerToMemberCasts() {
AFnPointer AFP = &A::bar;
BFnPointer StaticCastedBase2Derived = static_cast<BFnPointer>(&A::bar),
CCastedBase2Derived = (BFnPointer) (&A::bar);
A a;
B b;
clang_analyzer_eval((a.*AFP)() == 2); // expected-warning{{TRUE}}
clang_analyzer_eval((b.*StaticCastedBase2Derived)() == 2); // expected-warning{{TRUE}}
clang_analyzer_eval(((b.*CCastedBase2Derived)() == 2)); // expected-warning{{TRUE}}
}
void testPointerToMemberVirtualCall() {
A a;
B b;
A *APtr = &a;
AFnPointer AFP = &A::foo;
clang_analyzer_eval((APtr->*AFP)() == 1); // expected-warning{{TRUE}}
APtr = &b;
clang_analyzer_eval((APtr->*AFP)() == 3); // expected-warning{{TRUE}}
}
void testPointerToStaticMemberCall() {
int (*fPtr)(int) = &A::staticMemberFunction;
if (fPtr != 0) { // no-crash
clang_analyzer_eval(fPtr(2) == 3); // expected-warning{{TRUE}}
}
}
} // end of testPointerToMemberFunction namespace
namespace testPointerToMemberData {
struct A {
int i;
static int j;
};
void testPointerToMemberData() {
int A::*AMdPointer = &A::i;
A a;
a.i = 42;
a.*AMdPointer += 1;
clang_analyzer_eval(a.i == 43); // expected-warning{{TRUE}}
int *ptrToStaticField = &A::j;
if (ptrToStaticField != 0) {
*ptrToStaticField = 7;
clang_analyzer_eval(*ptrToStaticField == 7); // expected-warning{{TRUE}}
clang_analyzer_eval(A::j == 7); // expected-warning{{TRUE}}
}
}
} // end of testPointerToMemberData namespace
namespace testPointerToMemberMiscCasts {
struct B {
int f;
};
struct D : public B {
int g;
};
void foo() {
D d;
d.f = 7;
int B::* pfb = &B::f;
int D::* pfd = pfb;
int v = d.*pfd;
clang_analyzer_eval(v == 7); // expected-warning{{TRUE}}
}
} // end of testPointerToMemberMiscCasts namespace
namespace testPointerToMemberMiscCasts2 {
struct B {
int f;
};
struct L : public B { };
struct R : public B { };
struct D : public L, R { };
void foo() {
D d;
int B::* pb = &B::f;
int L::* pl = pb;
int R::* pr = pb;
int D::* pdl = pl;
int D::* pdr = pr;
clang_analyzer_eval(pdl == pdr); // expected-warning{{FALSE}}
clang_analyzer_eval(pb == pl); // expected-warning{{TRUE}}
}
} // end of testPointerToMemberMiscCasts2 namespace
namespace testPointerToMemberDiamond {
struct B {
int f;
};
struct L1 : public B { };
struct R1 : public B { };
struct M : public L1, R1 { };
struct L2 : public M { };
struct R2 : public M { };
struct D2 : public L2, R2 { };
void diamond() {
M m;
static_cast<L1 *>(&m)->f = 7;
static_cast<R1 *>(&m)->f = 16;
int L1::* pl1 = &B::f;
int M::* pm_via_l1 = pl1;
int R1::* pr1 = &B::f;
int M::* pm_via_r1 = pr1;
clang_analyzer_eval(m.*(pm_via_l1) == 7); // expected-warning {{TRUE}}
clang_analyzer_eval(m.*(pm_via_r1) == 16); // expected-warning {{TRUE}}
}
void double_diamond() {
D2 d2;
static_cast<L1 *>(static_cast<L2 *>(&d2))->f = 1;
static_cast<L1 *>(static_cast<R2 *>(&d2))->f = 2;
static_cast<R1 *>(static_cast<L2 *>(&d2))->f = 3;
static_cast<R1 *>(static_cast<R2 *>(&d2))->f = 4;
clang_analyzer_eval(d2.*(static_cast<int D2::*>(static_cast<int L2::*>(static_cast<int L1::*>(&B::f)))) == 1); // expected-warning {{TRUE}}
clang_analyzer_eval(d2.*(static_cast<int D2::*>(static_cast<int R2::*>(static_cast<int L1::*>(&B::f)))) == 2); // expected-warning {{TRUE}}
clang_analyzer_eval(d2.*(static_cast<int D2::*>(static_cast<int L2::*>(static_cast<int R1::*>(&B::f)))) == 3); // expected-warning {{TRUE}}
clang_analyzer_eval(d2.*(static_cast<int D2::*>(static_cast<int R2::*>(static_cast<int R1::*>(&B::f)))) == 4); // expected-warning {{TRUE}}
}
} // end of testPointerToMemberDiamond namespace
namespace testAnonymousMember {
struct A {
struct {
int x;
};
struct {
struct {
int y;
};
};
struct {
union {
int z;
};
};
};
void test() {
clang_analyzer_eval(&A::x); // expected-warning{{TRUE}}
clang_analyzer_eval(&A::y); // expected-warning{{TRUE}}
clang_analyzer_eval(&A::z); // expected-warning{{TRUE}}
int A::*l = &A::x, A::*m = &A::y, A::*n = &A::z;
clang_analyzer_eval(l); // expected-warning{{TRUE}}
clang_analyzer_eval(m); // expected-warning{{TRUE}}
clang_analyzer_eval(n); // expected-warning{{TRUE}}
// FIXME: These should be true as well.
A a;
a.x = 1;
clang_analyzer_eval(a.*l == 1); // expected-warning{{UNKNOWN}}
a.y = 2;
clang_analyzer_eval(a.*m == 2); // expected-warning{{UNKNOWN}}
a.z = 3;
clang_analyzer_eval(a.*n == 3); // expected-warning{{UNKNOWN}}
}
} // end of testAnonymousMember namespace