offsetof.cpp
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// RUN: %clang_cc1 -triple x86_64-apple-darwin10.0.0 -fsyntax-only -verify %s -Winvalid-offsetof -std=c++98
struct NonPOD {
virtual void f();
int m;
};
struct P {
NonPOD fieldThatPointsToANonPODType;
};
void f() {
int i = __builtin_offsetof(P, fieldThatPointsToANonPODType.m); // expected-warning{{offset of on non-POD type 'P'}}
}
struct Base { int x; };
struct Derived : Base { int y; };
int o = __builtin_offsetof(Derived, x); // expected-warning{{offset of on non-POD type}}
const int o2 = sizeof(__builtin_offsetof(Derived, x));
struct HasArray {
int array[17];
};
// Constant and non-constant offsetof expressions
void test_ice(int i) {
int array0[__builtin_offsetof(HasArray, array[5])];
int array1[__builtin_offsetof(HasArray, array[i])];
}
// Bitfields
struct has_bitfields {
int i : 7;
int j : 12; // expected-note{{bit-field is declared here}}
};
int test3 = __builtin_offsetof(struct has_bitfields, j); // expected-error{{cannot compute offset of bit-field 'j'}}
// offsetof referring to members of a base class.
struct Base1 {
int x;
};
struct Base2 {
int y;
};
struct Derived2 : public Base1, public Base2 {
int z;
};
int derived1[__builtin_offsetof(Derived2, x) == 0? 1 : -1];
int derived2[__builtin_offsetof(Derived2, y) == 4? 1 : -1];
int derived3[__builtin_offsetof(Derived2, z) == 8? 1 : -1];
// offsetof referring to anonymous struct in base.
// PR7769
struct foo {
struct {
int x;
};
};
struct bar : public foo {
};
int anonstruct[__builtin_offsetof(bar, x) == 0 ? 1 : -1];
struct LtoRCheck {
int a[10];
int f();
};
int ltor = __builtin_offsetof(struct LtoRCheck, a[LtoRCheck().f]); // \
expected-error {{reference to non-static member function must be called}}
namespace PR17578 {
struct Base {
int Field;
};
struct Derived : virtual Base {
void Fun() { (void)__builtin_offsetof(Derived, Field); } // expected-warning {{offset of on non-POD type}} \
expected-error {{invalid application of 'offsetof' to a field of a virtual base}}
};
}