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|
// RUN: %clang_cc1 -std=c++2a -fsyntax-only -triple x86_64-windows-msvc -fms-compatibility -fdump-record-layouts %s | FileCheck %s
namespace Empty {
struct A {};
struct A2 {};
struct A3 { [[msvc::no_unique_address]] A a; };
struct alignas(8) A4 {};
struct B {
[[msvc::no_unique_address]] A a;
char b;
};
static_assert(sizeof(B) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::B
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 0 | char b
// CHECK-NEXT: | [sizeof=1, align=1,
// CHECK-NEXT: | nvsize=1, nvalign=1]
struct C {
[[msvc::no_unique_address]] A a;
[[msvc::no_unique_address]] A2 a2;
char c;
};
static_assert(sizeof(C) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::C
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 0 | struct Empty::A2 a2 (empty)
// CHECK-NEXT: 0 | char c
// CHECK-NEXT: | [sizeof=1, align=1,
// CHECK-NEXT: | nvsize=1, nvalign=1]
struct D {
[[msvc::no_unique_address]] A3 a;
int i;
};
static_assert(sizeof(D) == 8);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::D
// CHECK-NEXT: 0 | struct Empty::A3 a (empty)
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 4 | int i
// CHECK-NEXT: | [sizeof=8, align=4,
// CHECK-NEXT: | nvsize=8, nvalign=4]
struct E {
[[msvc::no_unique_address]] A a1;
[[msvc::no_unique_address]] A a2;
char e;
};
static_assert(sizeof(E) == 2);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::E
// CHECK-NEXT: 0 | struct Empty::A a1 (empty)
// CHECK-NEXT: 1 | struct Empty::A a2 (empty)
// CHECK-NEXT: 0 | char e
// CHECK-NEXT: | [sizeof=2, align=1,
// CHECK-NEXT: | nvsize=2, nvalign=1]
struct F {
~F();
[[msvc::no_unique_address]] A a1;
[[msvc::no_unique_address]] A a2;
char f;
};
static_assert(sizeof(F) == 2);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::F
// CHECK-NEXT: 0 | struct Empty::A a1 (empty)
// CHECK-NEXT: 1 | struct Empty::A a2 (empty)
// CHECK-NEXT: 0 | char f
// CHECK-NEXT: | [sizeof=2, align=1,
// CHECK-NEXT: | nvsize=2, nvalign=1]
struct G { [[msvc::no_unique_address]] A a; ~G(); };
static_assert(sizeof(G) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::G
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: | [sizeof=1, align=1,
// CHECK-NEXT: | nvsize=1, nvalign=1]
struct H {
[[msvc::no_unique_address]] A a;
[[msvc::no_unique_address]] A b;
~H();
};
static_assert(sizeof(H) == 2);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::H
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 1 | struct Empty::A b (empty)
// CHECK-NEXT: | [sizeof=2, align=1,
// CHECK-NEXT: | nvsize=2, nvalign=1]
struct I {
[[msvc::no_unique_address]] A4 a;
[[msvc::no_unique_address]] A4 b;
};
static_assert(sizeof(I) == 16);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::I
// CHECK-NEXT: 0 | struct Empty::A4 a (empty)
// CHECK-NEXT: 8 | struct Empty::A4 b (empty)
// CHECK-NEXT: | [sizeof=16, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct J {
[[msvc::no_unique_address]] A4 a;
A4 b;
};
static_assert(sizeof(J) == 16);
// MSVC puts a and b at the same offset.
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::J
// CHECK-NEXT: 0 | struct Empty::A4 a (empty)
// CHECK-NEXT: 8 | struct Empty::A4 b (empty)
// CHECK-NEXT: | [sizeof=16, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct K {
[[msvc::no_unique_address]] A4 a;
[[msvc::no_unique_address]] char c;
[[msvc::no_unique_address]] A4 b;
};
static_assert(sizeof(K) == 16);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::K
// CHECK-NEXT: 0 | struct Empty::A4 a (empty)
// CHECK-NEXT: 0 | char c
// CHECK-NEXT: 8 | struct Empty::A4 b (empty)
// CHECK-NEXT: | [sizeof=16, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct OversizedEmpty : A {
~OversizedEmpty();
[[msvc::no_unique_address]] A a;
};
static_assert(sizeof(OversizedEmpty) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::OversizedEmpty
// CHECK-NEXT: 0 | struct Empty::A (base) (empty)
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: | [sizeof=1, align=1,
// CHECK-NEXT: | nvsize=1, nvalign=1]
struct HasOversizedEmpty {
[[msvc::no_unique_address]] OversizedEmpty m;
};
static_assert(sizeof(HasOversizedEmpty) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::HasOversizedEmpty
// CHECK-NEXT: 0 | struct Empty::OversizedEmpty m (empty)
// CHECK-NEXT: 0 | struct Empty::A (base) (empty)
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: | [sizeof=1, align=1,
// CHECK-NEXT: | nvsize=1, nvalign=1]
struct EmptyWithNonzeroDSize {
[[msvc::no_unique_address]] A a;
int x;
[[msvc::no_unique_address]] A b;
int y;
[[msvc::no_unique_address]] A c;
};
static_assert(sizeof(EmptyWithNonzeroDSize) == 8);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::EmptyWithNonzeroDSize
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 0 | int x
// CHECK-NEXT: 1 | struct Empty::A b (empty)
// CHECK-NEXT: 4 | int y
// CHECK-NEXT: 2 | struct Empty::A c (empty)
// CHECK-NEXT: | [sizeof=8, align=4,
// CHECK-NEXT: | nvsize=8, nvalign=4]
struct EmptyWithNonzeroDSizeNonPOD {
~EmptyWithNonzeroDSizeNonPOD();
[[msvc::no_unique_address]] A a;
int x;
[[msvc::no_unique_address]] A b;
int y;
[[msvc::no_unique_address]] A c;
};
static_assert(sizeof(EmptyWithNonzeroDSizeNonPOD) == 8);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct Empty::EmptyWithNonzeroDSizeNonPOD
// CHECK-NEXT: 0 | struct Empty::A a (empty)
// CHECK-NEXT: 0 | int x
// CHECK-NEXT: 1 | struct Empty::A b (empty)
// CHECK-NEXT: 4 | int y
// CHECK-NEXT: 2 | struct Empty::A c (empty)
// CHECK-NEXT: | [sizeof=8, align=4,
// CHECK-NEXT: | nvsize=8, nvalign=4]
}
namespace POD {
struct A { int n; char c[3]; };
struct B { [[msvc::no_unique_address]] A a; char d; };
static_assert(sizeof(B) == 12);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct POD::B
// CHECK-NEXT: 0 | struct POD::A a
// CHECK-NEXT: 0 | int n
// CHECK-NEXT: 4 | char[3] c
// CHECK-NEXT: 8 | char d
// CHECK-NEXT: | [sizeof=12, align=4,
// CHECK-NEXT: | nvsize=12, nvalign=4]
}
namespace NonPOD {
struct A { int n; char c[3]; ~A(); };
struct B { [[msvc::no_unique_address]] A a; char d; };
static_assert(sizeof(B) == 12);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct NonPOD::B
// CHECK-NEXT: 0 | struct NonPOD::A a
// CHECK-NEXT: 0 | int n
// CHECK-NEXT: 4 | char[3] c
// CHECK-NEXT: 8 | char d
// CHECK-NEXT: | [sizeof=12, align=4,
// CHECK-NEXT: | nvsize=12, nvalign=4]
}
namespace VBases {
// The nvsize of an object includes the complete size of its empty subobjects
// (although it's unclear why). Ensure this corner case is handled properly.
struct Empty {};
struct alignas(8) A {}; // dsize 0, nvsize 0, size 8
struct B : A { char c; }; // dsize 1, nvsize 8, size 8
static_assert(sizeof(B) == 8);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::B
// CHECK-NEXT: 0 | struct VBases::A (base) (empty)
// CHECK-NEXT: 0 | char c
// CHECK-NEXT: | [sizeof=8, align=8,
// CHECK-NEXT: | nvsize=8, nvalign=8]
struct V { int n; };
struct C : B, virtual V {};
static_assert(sizeof(C) == 24);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::C
// CHECK-NEXT: 0 | struct VBases::B (base)
// CHECK-NEXT: 0 | struct VBases::A (base) (empty)
// CHECK-NEXT: 0 | char c
// CHECK-NEXT: 8 | (C vbtable pointer)
// CHECK-NEXT: 16 | struct VBases::V (virtual base)
// CHECK-NEXT: 16 | int n
// CHECK-NEXT: | [sizeof=24, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct D : virtual Empty {
[[msvc::no_unique_address]] Empty a;
};
static_assert(sizeof(D) == 16);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::D
// CHECK-NEXT: 0 | (D vbtable pointer)
// CHECK-NEXT: 8 | struct VBases::Empty a
// CHECK-NEXT: 16 | struct VBases::Empty (virtual base) (empty)
// CHECK-NEXT: | [sizeof=16, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct E : virtual V {
[[msvc::no_unique_address]] B b;
};
static_assert(sizeof(E) == 24);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::E
// CHECK-NEXT: 0 | (E vbtable pointer)
// CHECK-NEXT: 8 | struct VBases::B b
// CHECK-NEXT: 8 | struct VBases::A (base) (empty)
// CHECK-NEXT: 8 | char c
// CHECK-NEXT: 16 | struct VBases::V (virtual base)
// CHECK-NEXT: 16 | int n
// CHECK-NEXT: | [sizeof=24, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
struct X : virtual A { [[msvc::no_unique_address]] A a; };
struct F : virtual A {
[[msvc::no_unique_address]] A a;
[[msvc::no_unique_address]] X x;
};
static_assert(sizeof(F) == 24);
// MSVC places x after a and the total size is 48.
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::F
// CHECK-NEXT: 0 | (F vbtable pointer)
// CHECK-NEXT: 8 | struct VBases::A a (empty)
// CHECK-NEXT: 8 | struct VBases::X x
// CHECK-NEXT: 8 | (X vbtable pointer)
// CHECK-NEXT: 16 | struct VBases::A a (empty)
// CHECK-NEXT: 24 | struct VBases::A (virtual base) (empty)
// CHECK-NEXT: 24 | struct VBases::A (virtual base) (empty)
// CHECK-NEXT: | [sizeof=24, align=8,
// CHECK-NEXT: | nvsize=24, nvalign=8]
struct G : virtual Empty {
int i;
[[msvc::no_unique_address]] A a;
};
static_assert(sizeof(G) == 16);
// MSVC places a at offset 12.
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct VBases::G
// CHECK-NEXT: 0 | (G vbtable pointer)
// CHECK-NEXT: 8 | int i
// CHECK-NEXT: 8 | struct VBases::A a (empty)
// CHECK-NEXT: 16 | struct VBases::Empty (virtual base) (empty)
// CHECK-NEXT: | [sizeof=16, align=8,
// CHECK-NEXT: | nvsize=16, nvalign=8]
}
namespace ZeroSize {
struct empty {};
union empty_union {};
struct empty_union_container {
[[msvc::no_unique_address]] empty_union x;
};
union union_of_empty {
[[msvc::no_unique_address]] empty x;
};
struct struct_of_empty {
[[msvc::no_unique_address]] empty x;
};
struct union_of_empty_container {
[[msvc::no_unique_address]] union_of_empty x;
};
static_assert(sizeof(union_of_empty_container) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct ZeroSize::union_of_empty_container
// CHECK-NOT: (empty)
// CHECK: 0 | union ZeroSize::union_of_empty x (empty)
// CHECK: 0 | struct ZeroSize::empty x (empty)
// CHECK: | [sizeof=1, align=1,
// CHECK: | nvsize=1, nvalign=1]
struct struct_of_empty_container {
[[msvc::no_unique_address]] struct_of_empty x;
};
static_assert(sizeof(struct_of_empty_container) == 1);
// CHECK:*** Dumping AST Record Layout
// CHECK: 0 | struct ZeroSize::struct_of_empty_container
// CHECK-NOT: (empty)
// CHECK: 0 | struct ZeroSize::struct_of_empty x (empty)
// CHECK: 0 | struct ZeroSize::empty x (empty)
// CHECK: | [sizeof=1, align=1,
// CHECK: | nvsize=1, nvalign=1]
}
|
