// RUN: %clang_cc1 -fsyntax-only -verify -ffreestanding -Wundefined-reinterpret-cast -Wno-unused-volatile-lvalue %s
#include <stdint.h>
enum test { testval = 1 };
struct structure { int m; };
typedef void (*fnptr)();
// Test the conversion to self.
void self_conversion()
{
// T->T is allowed per [expr.reinterpret.cast]p2 so long as it doesn't
// cast away constness, and is integral, enumeration, pointer or
// pointer-to-member.
int i = 0;
(void)reinterpret_cast<int>(i);
test e = testval;
(void)reinterpret_cast<test>(e);
// T*->T* is allowed
int *pi = 0;
(void)reinterpret_cast<int*>(pi);
const int structure::*psi = 0;
(void)reinterpret_cast<const int structure::*>(psi);
const int ci = 0;
(void)reinterpret_cast<const int>(i);
structure s;
(void)reinterpret_cast<structure>(s); // expected-error {{reinterpret_cast from 'structure' to 'structure' is not allowed}}
float f = 0.0f;
(void)reinterpret_cast<float>(f); // expected-error {{reinterpret_cast from 'float' to 'float' is not allowed}}
}
// Test conversion between pointer and integral types, as in /3 and /4.
void integral_conversion()
{
void *vp = reinterpret_cast<void*>(testval);
intptr_t i = reinterpret_cast<intptr_t>(vp);
(void)reinterpret_cast<float*>(i);
fnptr fnp = reinterpret_cast<fnptr>(i);
(void)reinterpret_cast<char>(fnp); // expected-error {{cast from pointer to smaller type 'char' loses information}}
(void)reinterpret_cast<intptr_t>(fnp);
}
void pointer_conversion()
{
int *p1 = 0;
float *p2 = reinterpret_cast<float*>(p1);
structure *p3 = reinterpret_cast<structure*>(p2);
typedef int **ppint;
ppint *deep = reinterpret_cast<ppint*>(p3);
(void)reinterpret_cast<fnptr*>(deep);
}
void constness()
{
int ***const ipppc = 0;
// Valid: T1* -> T2 const*
int const *icp = reinterpret_cast<int const*>(ipppc);
// Invalid: T1 const* -> T2*
(void)reinterpret_cast<int*>(icp); // expected-error {{reinterpret_cast from 'const int *' to 'int *' casts away qualifiers}}
// Invalid: T1*** -> T2 const* const**
int const *const **icpcpp = reinterpret_cast<int const* const**>(ipppc); // expected-error {{reinterpret_cast from 'int ***' to 'const int *const **' casts away qualifiers}}
// Valid: T1* -> T2*
int *ip = reinterpret_cast<int*>(icpcpp);
// Valid: T* -> T const*
(void)reinterpret_cast<int const*>(ip);
// Valid: T*** -> T2 const* const* const*
(void)reinterpret_cast<int const* const* const*>(ipppc);
// C++ [expr.type]/8.2.2:
// If a pr-value initially has the type cv-T, where T is a
// cv-unqualified non-class, non-array type, the type of the
// expression is adjusted to T prior to any further analysis.
int i = 0;
// Valid: T -> T (top level const is ignored)
(void)reinterpret_cast<const int>(i);
// Valid: T* -> T* (top level const is ignored)
(void)reinterpret_cast<int *const>(ip);
}
void fnptrs()
{
typedef int (*fnptr2)(int);
fnptr fp = 0;
(void)reinterpret_cast<fnptr2>(fp);
void *vp = reinterpret_cast<void*>(fp);
(void)reinterpret_cast<fnptr>(vp);
}
void refs()
{
long l = 0;
char &c = reinterpret_cast<char&>(l);
// Bad: from rvalue
(void)reinterpret_cast<int&>(&c); // expected-error {{reinterpret_cast from rvalue to reference type 'int &'}}
}
void memptrs()
{
const int structure::*psi = 0;
(void)reinterpret_cast<const float structure::*>(psi);
(void)reinterpret_cast<int structure::*>(psi); // expected-error {{reinterpret_cast from 'const int structure::*' to 'int structure::*' casts away qualifiers}}
void (structure::*psf)() = 0;
(void)reinterpret_cast<int (structure::*)()>(psf);
(void)reinterpret_cast<void (structure::*)()>(psi); // expected-error-re {{reinterpret_cast from 'const int structure::*' to 'void (structure::*)(){{( __attribute__\(\(thiscall\)\))?}}' is not allowed}}
(void)reinterpret_cast<int structure::*>(psf); // expected-error-re {{reinterpret_cast from 'void (structure::*)(){{( __attribute__\(\(thiscall\)\))?}}' to 'int structure::*' is not allowed}}
// Cannot cast from integers to member pointers, not even the null pointer
// literal.
(void)reinterpret_cast<void (structure::*)()>(0); // expected-error-re {{reinterpret_cast from 'int' to 'void (structure::*)(){{( __attribute__\(\(thiscall\)\))?}}' is not allowed}}
(void)reinterpret_cast<int structure::*>(0); // expected-error {{reinterpret_cast from 'int' to 'int structure::*' is not allowed}}
}
namespace PR5545 {
// PR5545
class A;
class B;
void (A::*a)();
void (B::*b)() = reinterpret_cast<void (B::*)()>(a);
}
void const_arrays() {
typedef char STRING[10];
const STRING *s;
const char *c;
(void)reinterpret_cast<char *>(s); // expected-error {{reinterpret_cast from 'const STRING *' (aka 'const char (*)[10]') to 'char *' casts away qualifiers}}
(void)reinterpret_cast<const STRING *>(c);
}
namespace PR9564 {
struct a { int a : 10; }; a x;
int *y = &reinterpret_cast<int&>(x.a); // expected-error {{reinterpret_cast from bit-field lvalue to reference type 'int &'}}
__attribute((ext_vector_type(4))) typedef float v4;
float& w(v4 &a) { return reinterpret_cast<float&>(a[1]); } // expected-error {{not allowed}}
}
void dereference_reinterpret_cast() {
struct A {};
typedef A A2;
class B {};
typedef B B2;
A a;
B b;
A2 a2;
B2 b2;
long l;
double d;
float f;
char c;
unsigned char uc;
void* v_ptr;
(void)reinterpret_cast<double&>(l); // expected-warning {{reinterpret_cast from 'long' to 'double &' has undefined behavior}}
(void)*reinterpret_cast<double*>(&l); // expected-warning {{dereference of type 'double *' that was reinterpret_cast from type 'long *' has undefined behavior}}
(void)reinterpret_cast<double&>(f); // expected-warning {{reinterpret_cast from 'float' to 'double &' has undefined behavior}}
(void)*reinterpret_cast<double*>(&f); // expected-warning {{dereference of type 'double *' that was reinterpret_cast from type 'float *' has undefined behavior}}
(void)reinterpret_cast<float&>(l); // expected-warning {{reinterpret_cast from 'long' to 'float &' has undefined behavior}}
(void)*reinterpret_cast<float*>(&l); // expected-warning {{dereference of type 'float *' that was reinterpret_cast from type 'long *' has undefined behavior}}
(void)reinterpret_cast<float&>(d); // expected-warning {{reinterpret_cast from 'double' to 'float &' has undefined behavior}}
(void)*reinterpret_cast<float*>(&d); // expected-warning {{dereference of type 'float *' that was reinterpret_cast from type 'double *' has undefined behavior}}
// TODO: add warning for tag types
(void)reinterpret_cast<A&>(b);
(void)*reinterpret_cast<A*>(&b);
(void)reinterpret_cast<B&>(a);
(void)*reinterpret_cast<B*>(&a);
(void)reinterpret_cast<A2&>(b2);
(void)*reinterpret_cast<A2*>(&b2);
(void)reinterpret_cast<B2&>(a2);
(void)*reinterpret_cast<B2*>(&a2);
// Casting to itself is allowed
(void)reinterpret_cast<A&>(a);
(void)*reinterpret_cast<A*>(&a);
(void)reinterpret_cast<B&>(b);
(void)*reinterpret_cast<B*>(&b);
(void)reinterpret_cast<long&>(l);
(void)*reinterpret_cast<long*>(&l);
(void)reinterpret_cast<double&>(d);
(void)*reinterpret_cast<double*>(&d);
(void)reinterpret_cast<char&>(c);
(void)*reinterpret_cast<char*>(&c);
// Casting to and from chars are allowable
(void)reinterpret_cast<A&>(c);
(void)*reinterpret_cast<A*>(&c);
(void)reinterpret_cast<B&>(c);
(void)*reinterpret_cast<B*>(&c);
(void)reinterpret_cast<long&>(c);
(void)*reinterpret_cast<long*>(&c);
(void)reinterpret_cast<double&>(c);
(void)*reinterpret_cast<double*>(&c);
(void)reinterpret_cast<char&>(l);
(void)*reinterpret_cast<char*>(&l);
(void)reinterpret_cast<char&>(d);
(void)*reinterpret_cast<char*>(&d);
(void)reinterpret_cast<char&>(f);
(void)*reinterpret_cast<char*>(&f);
// Casting from void pointer.
(void)*reinterpret_cast<A*>(v_ptr);
(void)*reinterpret_cast<B*>(v_ptr);
(void)*reinterpret_cast<long*>(v_ptr);
(void)*reinterpret_cast<double*>(v_ptr);
(void)*reinterpret_cast<float*>(v_ptr);
// Casting to void pointer
(void)*reinterpret_cast<void*>(&a); // expected-error {{indirection not permitted on operand of type 'void *'}}
(void)*reinterpret_cast<void*>(&b); // expected-error {{indirection not permitted on operand of type 'void *'}}
(void)*reinterpret_cast<void*>(&l); // expected-error {{indirection not permitted on operand of type 'void *'}}
(void)*reinterpret_cast<void*>(&d); // expected-error {{indirection not permitted on operand of type 'void *'}}
(void)*reinterpret_cast<void*>(&f); // expected-error {{indirection not permitted on operand of type 'void *'}}
}
void reinterpret_cast_allowlist () {
// the dynamic type of the object
int a;
float b;
(void)reinterpret_cast<int&>(a);
(void)*reinterpret_cast<int*>(&a);
(void)reinterpret_cast<float&>(b);
(void)*reinterpret_cast<float*>(&b);
// a cv-qualified version of the dynamic object
(void)reinterpret_cast<const int&>(a);
(void)*reinterpret_cast<const int*>(&a);
(void)reinterpret_cast<volatile int&>(a);
(void)*reinterpret_cast<volatile int*>(&a);
(void)reinterpret_cast<const volatile int&>(a);
(void)*reinterpret_cast<const volatile int*>(&a);
(void)reinterpret_cast<const float&>(b);
(void)*reinterpret_cast<const float*>(&b);
(void)reinterpret_cast<volatile float&>(b);
(void)*reinterpret_cast<volatile float*>(&b);
(void)reinterpret_cast<const volatile float&>(b);
(void)*reinterpret_cast<const volatile float*>(&b);
// a type that is the signed or unsigned type corresponding to the dynamic
// type of the object
signed d;
unsigned e;
(void)reinterpret_cast<signed&>(d);
(void)*reinterpret_cast<signed*>(&d);
(void)reinterpret_cast<signed&>(e);
(void)*reinterpret_cast<signed*>(&e);
(void)reinterpret_cast<unsigned&>(d);
(void)*reinterpret_cast<unsigned*>(&d);
(void)reinterpret_cast<unsigned&>(e);
(void)*reinterpret_cast<unsigned*>(&e);
// a type that is the signed or unsigned type corresponding a cv-qualified
// version of the dynamic type the object
(void)reinterpret_cast<const signed&>(d);
(void)*reinterpret_cast<const signed*>(&d);
(void)reinterpret_cast<const signed&>(e);
(void)*reinterpret_cast<const signed*>(&e);
(void)reinterpret_cast<const unsigned&>(d);
(void)*reinterpret_cast<const unsigned*>(&d);
(void)reinterpret_cast<const unsigned&>(e);
(void)*reinterpret_cast<const unsigned*>(&e);
(void)reinterpret_cast<volatile signed&>(d);
(void)*reinterpret_cast<volatile signed*>(&d);
(void)reinterpret_cast<volatile signed&>(e);
(void)*reinterpret_cast<volatile signed*>(&e);
(void)reinterpret_cast<volatile unsigned&>(d);
(void)*reinterpret_cast<volatile unsigned*>(&d);
(void)reinterpret_cast<volatile unsigned&>(e);
(void)*reinterpret_cast<volatile unsigned*>(&e);
(void)reinterpret_cast<const volatile signed&>(d);
(void)*reinterpret_cast<const volatile signed*>(&d);
(void)reinterpret_cast<const volatile signed&>(e);
(void)*reinterpret_cast<const volatile signed*>(&e);
(void)reinterpret_cast<const volatile unsigned&>(d);
(void)*reinterpret_cast<const volatile unsigned*>(&d);
(void)reinterpret_cast<const volatile unsigned&>(e);
(void)*reinterpret_cast<const volatile unsigned*>(&e);
// an aggregate or union type that includes one of the aforementioned types
// among its members (including, recursively, a member of a subaggregate or
// contained union)
// TODO: checking is not implemented for tag types
// a type that is a (possible cv-qualified) base class type of the dynamic
// type of the object
// TODO: checking is not implemented for tag types
// a char or unsigned char type
(void)reinterpret_cast<char&>(a);
(void)*reinterpret_cast<char*>(&a);
(void)reinterpret_cast<unsigned char&>(a);
(void)*reinterpret_cast<unsigned char*>(&a);
(void)reinterpret_cast<char&>(b);
(void)*reinterpret_cast<char*>(&b);
(void)reinterpret_cast<unsigned char&>(b);
(void)*reinterpret_cast<unsigned char*>(&b);
}
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