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| // RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.core,debug.ExprInspection -analyzer-store=region -verify -Wno-null-dereference -Wno-tautological-undefined-compare -analyzer-config eagerly-assume=false %s
void clang_analyzer_eval(bool);
typedef typeof(sizeof(int)) size_t;
void malloc (size_t);
void f1() {
int const &i = 3;
int b = i;
int *p = 0;
if (b != 3)
*p = 1; // no-warning
}
char* ptr();
char& ref();
// These next two tests just shouldn't crash.
char t1 () {
ref() = 'c';
return '0';
}
// just a sanity test, the same behavior as t1()
char t2 () {
*ptr() = 'c';
return '0';
}
// Each of the tests below is repeated with pointers as well as references.
// This is mostly a sanity check, but then again, both should work!
char t3 () {
char& r = ref();
r = 'c'; // no-warning
if (r) return r;
return *(char*)0; // no-warning
}
char t4 () {
char* p = ptr();
*p = 'c'; // no-warning
if (*p) return *p;
return *(char*)0; // no-warning
}
char t5 (char& r) {
r = 'c'; // no-warning
if (r) return r;
return *(char*)0; // no-warning
}
char t6 (char* p) {
*p = 'c'; // no-warning
if (*p) return *p;
return *(char*)0; // no-warning
}
// PR13440 / <rdar://problem/11977113>
// Test that the array-to-pointer decay works for array references as well.
// More generally, when we want an lvalue for a reference field, we still need
// to do one level of load.
namespace PR13440 {
typedef int T[1];
struct S {
T &x;
int *m() { return x; }
};
struct S2 {
int (&x)[1];
int *m() { return x; }
void testArrayToPointerDecayWithNonTypedValueRegion() {
int *p = x;
int *q = x;
clang_analyzer_eval(p[0] == q[0]); // expected-warning{{TRUE}}
}
};
void test() {
int a[1];
S s = { a };
S2 s2 = { a };
if (s.x != a) return;
if (s2.x != a) return;
a[0] = 42;
clang_analyzer_eval(s.x[0] == 42); // expected-warning{{TRUE}}
clang_analyzer_eval(s2.x[0] == 42); // expected-warning{{TRUE}}
}
}
void testNullReference() {
int *x = 0;
int &y = *x; // expected-warning{{Dereference of null pointer}}
y = 5;
}
void testRetroactiveNullReference(int *x) {
// According to the C++ standard, there is no such thing as a
// "null reference". So the 'if' statement ought to be dead code.
// However, Clang (and other compilers) don't actually check that a pointer
// value is non-null in the implementation of references, so it is possible
// to produce a supposed "null reference" at runtime. The analyzer should
// still warn when it can prove such errors.
int &y = *x;
if (x != 0)
return;
y = 5; // expected-warning{{Dereference of null pointer}}
}
namespace TestReferenceAddress {
struct S { int &x; };
S getS();
S *getSP();
void testReferenceAddress(int &x) {
// FIXME: Move non-zero reference assumption out of RangeConstraintManager.cpp:422
#ifdef ANALYZER_CM_Z3
clang_analyzer_eval(&x != 0); // expected-warning{{UNKNOWN}}
clang_analyzer_eval(&ref() != 0); // expected-warning{{UNKNOWN}}
#else
clang_analyzer_eval(&x != 0); // expected-warning{{TRUE}}
clang_analyzer_eval(&ref() != 0); // expected-warning{{TRUE}}
#endif
#ifdef ANALYZER_CM_Z3
clang_analyzer_eval(&getS().x != 0); // expected-warning{{UNKNOWN}}
#else
clang_analyzer_eval(&getS().x != 0); // expected-warning{{TRUE}}
#endif
#ifdef ANALYZER_CM_Z3
clang_analyzer_eval(&getSP()->x != 0); // expected-warning{{UNKNOWN}}
#else
clang_analyzer_eval(&getSP()->x != 0); // expected-warning{{TRUE}}
#endif
}
}
void testFunctionPointerReturn(void *opaque) {
typedef int &(*RefFn)();
RefFn getRef = (RefFn)opaque;
// Don't crash writing to or reading from this reference.
int &x = getRef();
x = 42;
clang_analyzer_eval(x == 42); // expected-warning{{TRUE}}
}
int &testReturnNullReference() {
int *x = 0;
return *x; // expected-warning{{Returning null reference}}
}
char &refFromPointer() {
return *ptr();
}
void testReturnReference() {
clang_analyzer_eval(ptr() == 0); // expected-warning{{UNKNOWN}}
clang_analyzer_eval(&refFromPointer() == 0); // expected-warning{{FALSE}}
}
void intRefParam(int &r) {
;
}
void test(int *ptr) {
clang_analyzer_eval(ptr == 0); // expected-warning{{UNKNOWN}}
extern void use(int &ref);
use(*ptr);
clang_analyzer_eval(ptr == 0); // expected-warning{{FALSE}}
}
void testIntRefParam() {
int i = 0;
intRefParam(i); // no-warning
}
int refParam(int &byteIndex) {
return byteIndex;
}
void testRefParam(int *p) {
if (p)
;
refParam(*p); // expected-warning {{Forming reference to null pointer}}
}
int ptrRefParam(int *&byteIndex) {
return *byteIndex; // expected-warning {{Dereference of null pointer}}
}
void testRefParam2() {
int *p = 0;
int *&rp = p;
ptrRefParam(rp);
}
int *maybeNull() {
extern bool coin();
static int x;
return coin() ? &x : 0;
}
void use(int &x) {
x = 1; // no-warning
}
void testSuppression() {
use(*maybeNull());
}
namespace rdar11212286 {
class B{};
B test() {
B *x = 0;
return *x; // expected-warning {{Forming reference to null pointer}}
}
B testif(B *x) {
if (x)
;
return *x; // expected-warning {{Forming reference to null pointer}}
}
void idc(B *x) {
if (x)
;
}
B testidc(B *x) {
idc(x);
return *x; // no-warning
}
}
namespace PR15694 {
class C {
bool bit : 1;
template <class T> void bar(const T &obj) {}
void foo() {
bar(bit); // don't crash
}
};
}
|