blob: 9a2fb678de664081b4395dd83e34232ebfb5bcdf [file] [log] [blame]
// RUN: %clang_cc1 %s -triple %itanium_abi_triple -fsyntax-only -verify -Wc++-compat
// Note: Empty C structs are 4 bytes in the Microsoft ABI.
struct emp_1 { // expected-warning {{empty struct has size 0 in C, size 1 in C++}}
};
union emp_2 { // expected-warning {{empty union has size 0 in C, size 1 in C++}}
};
struct emp_3 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
int : 0;
};
union emp_4 { // expected-warning {{union has size 0 in C, size 1 in C++}}
int : 0;
};
struct emp_5 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
int : 0;
int : 0;
};
union emp_6 { // expected-warning {{union has size 0 in C, size 1 in C++}}
int : 0;
int : 0;
};
struct emp_7 { // expected-warning {{struct has size 0 in C, size 1 in C++}}
struct emp_1 f1;
};
union emp_8 { // expected-warning {{union has size 0 in C, size 1 in C++}}
struct emp_1 f1;
};
struct emp_9 { // expected-warning {{struct has size 0 in C, non-zero size in C++}}
struct emp_1 f1;
union emp_2 f2;
};
// Checks for pointer subtraction (PR15683)
struct emp_1 *func_1p(struct emp_1 *x) { return x - 5; }
int func_1() {
struct emp_1 v[1];
return v - v; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
}
int func_2(struct emp_1 *x) {
return 1 + x - x; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
}
int func_3(struct emp_1 *x, struct emp_1 *y) {
return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
}
int func_4(struct emp_1 *x, const struct emp_1 *y) {
return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
}
int func_5(volatile struct emp_1 *x, const struct emp_1 *y) {
return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1' of zero size has undefined behavior}}
}
int func_6() {
union emp_2 v[1];
return v - v; // expected-warning {{subtraction of pointers to type 'union emp_2' of zero size has undefined behavior}}
}
struct A; // expected-note {{forward declaration of 'struct A'}}
int func_7(struct A *x, struct A *y) {
return x - y; // expected-error {{arithmetic on a pointer to an incomplete type 'struct A'}}
}
int func_8(struct emp_1 (*x)[10], struct emp_1 (*y)[10]) {
return x - y; // expected-warning {{subtraction of pointers to type 'struct emp_1 [10]' of zero size has undefined behavior}}
}
int func_9(struct emp_1 (*x)[], struct emp_1 (*y)[]) {
return x - y; // expected-error {{arithmetic on a pointer to an incomplete type 'struct emp_1 []'}}
}
int func_10(int (*x)[0], int (*y)[0]) {
return x - y; // expected-warning {{subtraction of pointers to type 'int [0]' of zero size has undefined behavior}}
}