| 1 | // RUN: %clang_cc1 -fsyntax-only -triple armv7k-apple-darwin-watchos -fdump-record-layouts %s | FileCheck %s |
|---|
| 2 | |
|---|
| 3 | // WatchOS, 64-bit iOS, and WebAssembly use the C++11 definition of POD to |
|---|
| 4 | // determine whether we can reuse the tail padding of a struct (POD is |
|---|
| 5 | // "trivially copyable and standard layout"). The definition of standard |
|---|
| 6 | // layout changed some time around C++17; check that we still use the old |
|---|
| 7 | // ABI rule. |
|---|
| 8 | |
|---|
| 9 | // B is not standard-layout, but it was under C++11's rule, so we pack |
|---|
| 10 | // C::d into its tail padding anyway. |
|---|
| 11 | struct A { int : 0; }; |
|---|
| 12 | struct B : A { int n; char c[3]; }; |
|---|
| 13 | struct C : B { char d; }; |
|---|
| 14 | int c = sizeof(C); |
|---|
| 15 | static_assert(!__is_standard_layout(B)); |
|---|
| 16 | |
|---|
| 17 | // CHECK:*** Dumping AST Record Layout |
|---|
| 18 | // CHECK: 0 | struct C |
|---|
| 19 | // CHECK-NEXT: 0 | struct B (base) |
|---|
| 20 | // CHECK-NEXT: 0 | struct A (base) (empty) |
|---|
| 21 | // CHECK-NEXT: 0:- | int |
|---|
| 22 | // CHECK-NEXT: 0 | int n |
|---|
| 23 | // CHECK-NEXT: 4 | char [3] c |
|---|
| 24 | // CHECK-NEXT: 8 | char d |
|---|
| 25 | // CHECK-NEXT: | [sizeof=12, dsize=9, align=4, |
|---|
| 26 | // CHECK-NEXT: | nvsize=9, nvalign=4] |
|---|
| 27 | |
|---|
| 28 | // F is not standard-layout due to the repeated D base class, but it was under |
|---|
| 29 | // C++11's rule, so we pack G::d into its tail padding anyway. |
|---|
| 30 | struct D {}; |
|---|
| 31 | struct E : D {}; |
|---|
| 32 | struct F : D, E { int n; char c[3]; }; |
|---|
| 33 | struct G : F { G(const G&); char d; }; |
|---|
| 34 | int g = sizeof(G); |
|---|
| 35 | static_assert(!__is_standard_layout(F)); |
|---|
| 36 | |
|---|
| 37 | // CHECK:*** Dumping AST Record Layout |
|---|
| 38 | // CHECK: 0 | struct G |
|---|
| 39 | // CHECK-NEXT: 0 | struct F (base) |
|---|
| 40 | // CHECK-NEXT: 0 | struct D (base) (empty) |
|---|
| 41 | // CHECK-NEXT: 1 | struct E (base) (empty) |
|---|
| 42 | // CHECK-NEXT: 1 | struct D (base) (empty) |
|---|
| 43 | // CHECK-NEXT: 0 | int n |
|---|
| 44 | // CHECK-NEXT: 4 | char [3] c |
|---|
| 45 | // CHECK-NEXT: 8 | char d |
|---|
| 46 | // CHECK-NEXT: | [sizeof=12, dsize=9, align=4, |
|---|
| 47 | // CHECK-NEXT: | nvsize=9, nvalign=4] |
|---|
| 48 | |
|---|