xref: /llvm-project/libcxxabi/test/test_exception_address_alignment.pass.cpp (revision 3497500946c9b6a1b2e1452312a24c41ee412b34)
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 // Test that the address of the exception object is properly aligned as required
13 // by the relevant ABI
14 
15 #include <cstdint>
16 #include <cassert>
17 #include <__cxxabi_config.h>
18 
19 #include <unwind.h>
20 
21 struct __attribute__((aligned)) AlignedType {};
22 
23 // EHABI  : 8-byte aligned
24 // Itanium: Largest supported alignment for the system
25 #if defined(_LIBCXXABI_ARM_EHABI)
26 #  define EXPECTED_ALIGNMENT 8
27 #else
28 #  define EXPECTED_ALIGNMENT alignof(AlignedType)
29 #endif
30 
31 static_assert(alignof(_Unwind_Exception) == EXPECTED_ALIGNMENT,
32   "_Unwind_Exception is incorrectly aligned. This test is expected to fail");
33 
34 struct MinAligned {  };
35 static_assert(alignof(MinAligned) == 1 && sizeof(MinAligned) == 1, "");
36 
main(int,char **)37 int main(int, char**) {
38   for (int i=0; i < 10; ++i) {
39     try {
40       throw MinAligned{};
41     } catch (MinAligned const& ref) {
42       assert(reinterpret_cast<uintptr_t>(&ref) % EXPECTED_ALIGNMENT == 0);
43     }
44   }
45 
46   return 0;
47 }
48