nullptr.cpp
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// RUN: %clang_analyze_cc1 -std=c++11 -Wno-conversion-null -analyzer-checker=core,debug.ExprInspection -analyzer-store region -analyzer-output=text -verify %s
void clang_analyzer_eval(int);
// test to see if nullptr is detected as a null pointer
void foo1(void) {
char *np = nullptr; // expected-note{{'np' initialized to a null pointer value}}
*np = 0; // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
}
// check if comparing nullptr to nullptr is detected properly
void foo2(void) {
char *np1 = nullptr;
char *np2 = np1;
char c;
if (np1 == np2)
np1 = &c;
*np1 = 0; // no-warning
}
// invoving a nullptr in a more complex operation should be cause a warning
void foo3(void) {
struct foo {
int a, f;
};
char *np = nullptr; // expected-note{{'np' initialized to a null pointer value}}
// casting a nullptr to anything should be caught eventually
int *ip = &(((struct foo *)np)->f); // expected-note{{'ip' initialized to a null pointer value}}
*ip = 0; // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
// should be error here too, but analysis gets stopped
// *np = 0;
}
// nullptr is implemented as a zero integer value, so should be able to compare
void foo4(void) {
char *np = nullptr;
if (np != 0)
*np = 0; // no-warning
char *cp = 0;
if (np != cp)
*np = 0; // no-warning
}
int pr10372(void *& x) {
// GNU null is a pointer-sized integer, not a pointer.
x = __null;
// This used to crash.
return __null;
}
void zoo1() {
char **p = 0; // expected-note{{'p' initialized to a null pointer value}}
delete *(p + 0); // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
}
void zoo1backwards() {
char **p = 0; // expected-note{{'p' initialized to a null pointer value}}
delete *(0 + p); // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
}
typedef __INTPTR_TYPE__ intptr_t;
void zoo1multiply() {
char **p = 0; // FIXME-should-be-note:{{'p' initialized to a null pointer value}}
delete *((char **)((intptr_t)p * 2)); // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
}
void zoo2() {
int **a = 0;
int **b = 0; // expected-note{{'b' initialized to a null pointer value}}
asm ("nop"
:"=r"(*a)
:"0"(*b) // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
);
}
int exprWithCleanups() {
struct S {
S(int a):a(a){}
~S() {}
int a;
};
int *x = 0; // expected-note{{'x' initialized to a null pointer value}}
return S(*x).a; // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
}
int materializeTempExpr() {
int *n = 0; // expected-note{{'n' initialized to a null pointer value}}
struct S {
int a;
S(int i): a(i) {}
};
const S &s = S(*n); // expected-warning{{Dereference of null pointer}}
// expected-note@-1{{Dereference of null pointer}}
return s.a;
}
typedef decltype(nullptr) nullptr_t;
void testMaterializeTemporaryExprWithNullPtr() {
// Create MaterializeTemporaryExpr with a nullptr inside.
const nullptr_t &r = nullptr;
}
int getSymbol();
struct X {
virtual void f() {}
};
void invokeF(X* x) {
x->f(); // expected-warning{{Called C++ object pointer is null}}
// expected-note@-1{{Called C++ object pointer is null}}
}
struct Type {
decltype(nullptr) x;
};
void shouldNotCrash() {
decltype(nullptr) p; // expected-note{{'p' declared without an initial value}}
if (getSymbol()) // expected-note {{Assuming the condition is false}}
// expected-note@-1{{Taking false branch}}
// expected-note@-2{{Assuming the condition is true}}
// expected-note@-3{{Taking true branch}}
invokeF(p); // expected-note {{Calling 'invokeF'}}
// expected-note@-1{{Passing null pointer value via 1st parameter 'x'}}
if (getSymbol()) { // expected-note {{Assuming the condition is true}}
// expected-note@-1{{Taking true branch}}
X *xx = Type().x; // expected-note {{Null pointer value stored to field 'x'}}
// expected-note@-1{{'xx' initialized to a null pointer value}}
xx->f(); // expected-warning{{Called C++ object pointer is null}}
// expected-note@-1{{Called C++ object pointer is null}}
}
}
void f(decltype(nullptr) p) {
int *q = nullptr;
clang_analyzer_eval(p == 0); // expected-warning{{TRUE}}
// expected-note@-1{{TRUE}}
clang_analyzer_eval(q == 0); // expected-warning{{TRUE}}
// expected-note@-1{{TRUE}}
}
decltype(nullptr) returnsNullPtrType();
void fromReturnType() {
((X *)returnsNullPtrType())->f(); // expected-warning{{Called C++ object pointer is null}}
// expected-note@-1{{Called C++ object pointer is null}}
}
#define AS_ATTRIBUTE __attribute__((address_space(256)))
class AS1 {
public:
int x;
~AS1() {
int AS_ATTRIBUTE *x = 0;
*x = 3; // no-warning
}
};
void test_address_space_field_access() {
AS1 AS_ATTRIBUTE *pa = 0;
pa->x = 0; // no-warning
}
void test_address_space_bind() {
AS1 AS_ATTRIBUTE *pa = 0;
AS1 AS_ATTRIBUTE &r = *pa;
r.x = 0; // no-warning
}