1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: no-exceptions
10 // UNSUPPORTED: c++03
11 
12 // The <unwind.h> header provided in the SDK of older Xcodes used to provide
13 // an incorrectly aligned _Unwind_Exception type. That causes these tests to
14 // fail with those SDKs.
15 // FIXME: We mark the test as unsupported on Apple until we have a Lit feature
16 //        representing the SDK version.
17 // UNSUPPORTED: darwin
18 
19 // Test that the address of the exception object is properly aligned as required
20 // by the relevant ABI
21 
22 #include <cstdint>
23 #include <cassert>
24 #include <__cxxabi_config.h>
25 
26 #include <unwind.h>
27 
28 struct __attribute__((aligned)) AlignedType {};
29 
30 // EHABI  : 8-byte aligned
31 // Itanium: Largest supported alignment for the system
32 #if defined(_LIBCXXABI_ARM_EHABI)
33 #  define EXPECTED_ALIGNMENT 8
34 #else
35 #  define EXPECTED_ALIGNMENT alignof(AlignedType)
36 #endif
37 
38 static_assert(alignof(_Unwind_Exception) == EXPECTED_ALIGNMENT,
39   "_Unwind_Exception is incorrectly aligned. This test is expected to fail");
40 
41 struct MinAligned {  };
42 static_assert(alignof(MinAligned) == 1 && sizeof(MinAligned) == 1, "");
43 
main(int,char **)44 int main(int, char**) {
45   for (int i=0; i < 10; ++i) {
46     try {
47       throw MinAligned{};
48     } catch (MinAligned const& ref) {
49       assert(reinterpret_cast<uintptr_t>(&ref) % EXPECTED_ALIGNMENT == 0);
50     }
51   }
52 
53   return 0;
54 }
55