test_dwarf failures on s390x

[davide125]

While building 0.0.13 for s390x there are some new test failures:

=================================== FAILURES ===================================
___________________ TestObjects.test_variable_expr_op_deref ____________________
self = <tests.test_dwarf.TestObjects testMethod=test_variable_expr_op_deref>
    def test_variable_expr_op_deref(self):
        for bits in (64, 32):
            for little_endian in (True, False):
                with self.subTest(bits=bits, little_endian=little_endian):
>                   self._assert_dwarf_expr_eval(
                        [
                            assembler.U8(DW_OP.addr),
                            (assembler.U64 if bits == 64 else assembler.U32)(
                                0xFFFF0000
                            ),
                            assembler.U8(DW_OP.deref),
                        ],
                        0x12345678,
                        bits=bits,
                        little_endian=little_endian,
                        segments=[
                            MockMemorySegment(
                                (0x12345678).to_bytes(
                                    bits // 8, "little" if little_endian else "big"
                                ),
                                0xFFFF0000,
                            )
                        ],
                    )
tests/test_dwarf.py:4801: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/test_dwarf.py:4640: in _assert_dwarf_expr_eval
    self.assertEqual(self._eval_dwarf_expr(ops, **kwds), expected)
E   AssertionError: 4294901760 != 305419896
_________________ TestObjects.test_variable_expr_op_deref_size _________________
self = <tests.test_dwarf.TestObjects testMethod=test_variable_expr_op_deref_size>
    def test_variable_expr_op_deref_size(self):
        for bits in (64, 32):
            for little_endian in (True, False):
                with self.subTest(bits=bits, little_endian=little_endian):
>                   self._assert_dwarf_expr_eval(
                        [
                            assembler.U8(DW_OP.addr),
                            (assembler.U64 if bits == 64 else assembler.U32)(
                                0xFFFF0000
                            ),
                            assembler.U8(DW_OP.deref_size),
                            assembler.U8(2),
                        ],
                        0x1337,
                        bits=bits,
                        little_endian=little_endian,
                        segments=[
                            MockMemorySegment(
                                (0x1337).to_bytes(
                                    2, "little" if little_endian else "big"
                                ),
                                0xFFFF0000,
                            )
                        ],
                    )
tests/test_dwarf.py:4836: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/test_dwarf.py:4640: in _assert_dwarf_expr_eval
    self.assertEqual(self._eval_dwarf_expr(ops, **kwds), expected)
E   AssertionError: 0 != 4919
=========================== short test summary info ============================
FAILED tests/test_dwarf.py::TestObjects::test_variable_expr_op_deref - Assert...
FAILED tests/test_dwarf.py::TestObjects::test_variable_expr_op_deref_size - A...
================== 2 failed, 479 passed, 54 skipped in 2.34s ===================

See https://koji.fedoraproject.org/koji/taskinfo?taskID=69592358 for the full log.

[osandov]

Thanks, I can reproduce this in my VM. It looks like it only affects big-endian hosts debugging little-endian core dumps, which should be a rare occurrence. I'll fix it up.

(This also shows that I need to get other architectures running in CI, but for now I'll add it to my release runbook to run tests in a VM before cutting a release.)