llvm-capstone/libcxxabi/test/test_exception_address_alignment.pass.cpp
Louis Dionne ed61d6a466 [libc++] Use the stdlib=<LIB> Lit feature instead of use_system_cxx_lib
The use_system_cxx_lib Lit feature was only used for back-deployment
testing. However, one immense hole in that setup was that we didn't
have a proper way to test Apple's own libc++ outside of back-deployment,
which was embodied by the fact that we needed to define _LIBCPP_DISABLE_AVAILABILITY
when testing (see change in libcxx/utils/libcxx/test/params.py).

This led to the apple-system testing configuration not checking for
availability markup, which is obviously quite bad since the library
we ship actually has availability markup.

Using stdlib=<VENDOR>-libc++ instead to encode back-deployment restrictions
on tests is simpler and it makes it possible to naturally support tests
such as availability markup checking even in the tip-of-trunk Apple-libc++
configuration.

Differential Revision: https://reviews.llvm.org/D146366
2023-03-30 06:57:56 -04:00

54 lines
1.7 KiB
C++

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: no-exceptions
// UNSUPPORTED: c++03
// The <unwind.h> header provided in the SDK of older Xcodes used to provide
// an incorrectly aligned _Unwind_Exception type on non-ARM. That causes these
// tests to fail when running against a system libc++abi and libunwind that was
// compiled with an incorrect definition of _Unwind_Exception.
// XFAIL: stdlib=apple-libc++ && target={{.+}}-apple-macosx10.{{9|10|11|12}}
// Test that the address of the exception object is properly aligned as required
// by the relevant ABI
#include <cstdint>
#include <cassert>
#include <__cxxabi_config.h>
#include <unwind.h>
struct __attribute__((aligned)) AlignedType {};
// EHABI : 8-byte aligned
// Itanium: Largest supported alignment for the system
#if defined(_LIBCXXABI_ARM_EHABI)
# define EXPECTED_ALIGNMENT 8
#else
# define EXPECTED_ALIGNMENT alignof(AlignedType)
#endif
static_assert(alignof(_Unwind_Exception) == EXPECTED_ALIGNMENT,
"_Unwind_Exception is incorrectly aligned. This test is expected to fail");
struct MinAligned { };
static_assert(alignof(MinAligned) == 1 && sizeof(MinAligned) == 1, "");
int main(int, char**) {
for (int i=0; i < 10; ++i) {
try {
throw MinAligned{};
} catch (MinAligned const& ref) {
assert(reinterpret_cast<uintptr_t>(&ref) % EXPECTED_ALIGNMENT == 0);
}
}
return 0;
}