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// RUN: %clang_cc1 -fsyntax-only -verify %s
namespace BooleanFalse {
int* j = false; // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
void foo(int* i, int *j=(false)) // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
{
foo(false); // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
foo((int*)false); // no-warning: explicit cast
foo(0); // no-warning: not a bool, even though its convertible to bool
foo(false == true); // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
foo((42 + 24) < 32); // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
const bool kFlag = false;
foo(kFlag); // expected-warning{{initialization of pointer of type 'int *' to null from a constant boolean expression}}
}
char f(struct Undefined*);
double f(...);
// Ensure that when using false in metaprogramming machinery its conversion
// isn't flagged.
template <int N> struct S {};
S<sizeof(f(false))> s;
}
namespace Function {
void f1();
struct S {
static void f2();
};
extern void f3() __attribute__((weak_import));
struct S2 {
static void f4() __attribute__((weak_import));
};
bool f5();
bool f6(int);
void bar() {
bool b;
b = f1; // expected-warning {{address of function 'f1' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
if (f1) {} // expected-warning {{address of function 'f1' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
b = S::f2; // expected-warning {{address of function 'S::f2' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
if (S::f2) {} // expected-warning {{address of function 'S::f2' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
b = f5; // expected-warning {{address of function 'f5' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}} \
expected-note {{suffix with parentheses to turn this into a function call}}
b = f6; // expected-warning {{address of function 'f6' will always evaluate to 'true'}} \
expected-note {{prefix with the address-of operator to silence this warning}}
// implicit casts of weakly imported symbols are ok:
b = f3;
if (f3) {}
b = S2::f4;
if (S2::f4) {}
}
}
namespace Array {
#define GetValue(ptr) ((ptr) ? ptr[0] : 0)
extern int a[] __attribute__((weak));
int b[] = {8,13,21};
struct {
int x[10];
} c;
const char str[] = "text";
void ignore() {
if (a) {}
if (a) {}
(void)GetValue(b);
}
void test() {
if (b) {}
// expected-warning@-1{{address of array 'b' will always evaluate to 'true'}}
if (b) {}
// expected-warning@-1{{address of array 'b' will always evaluate to 'true'}}
if (c.x) {}
// expected-warning@-1{{address of array 'c.x' will always evaluate to 'true'}}
if (str) {}
// expected-warning@-1{{address of array 'str' will always evaluate to 'true'}}
}
}
namespace Pointer {
extern int a __attribute__((weak));
int b;
static int c;
class S {
public:
static int a;
int b;
};
void ignored() {
if (&a) {}
}
void test() {
S s;
if (&b) {}
// expected-warning@-1{{address of 'b' will always evaluate to 'true'}}
if (&c) {}
// expected-warning@-1{{address of 'c' will always evaluate to 'true'}}
if (&s.a) {}
// expected-warning@-1{{address of 's.a' will always evaluate to 'true'}}
if (&s.b) {}
// expected-warning@-1{{address of 's.b' will always evaluate to 'true'}}
if (&S::a) {}
// expected-warning@-1{{address of 'S::a' will always evaluate to 'true'}}
}
}
namespace macros {
#define assert(x) if (x) {}
#define zero_on_null(x) ((x) ? *(x) : 0)
int array[5];
void fun();
int x;
void test() {
assert(array);
assert(array && "expecting null pointer");
// expected-warning@-1{{address of array 'array' will always evaluate to 'true'}}
assert(fun);
assert(fun && "expecting null pointer");
// expected-warning@-1{{address of function 'fun' will always evaluate to 'true'}}
// expected-note@-2 {{prefix with the address-of operator to silence this warning}}
// TODO: warn on assert(&x) while not warning on zero_on_null(&x)
zero_on_null(&x);
assert(zero_on_null(&x));
assert(&x);
assert(&x && "expecting null pointer");
// expected-warning@-1{{address of 'x' will always evaluate to 'true'}}
}
}
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