The ODB backend class uses PyArgs_ParseTuple with format identifier "n" to parse git_object_t type IDs. However, enums are not necessarily of type Py_ssize_t; in fact, the C standard does not constrain the underlying integer type. On big endian architectures such as s390x, this leads to unwanted cutoffs of the lower bits, yielding 0 instead of 3 as object type in tests/test_odb_backend.py.
This PR works around the issue by parsing the type into a well-known integer type first, and then casting to the git_object_t enum type, avoiding the undefined behavior.
The ODB backend class uses
PyArgs_ParseTuplewith format identifier"n"to parsegit_object_ttype IDs. However,enums are not necessarily of typePy_ssize_t; in fact, the C standard does not constrain the underlying integer type. On big endian architectures such as s390x, this leads to unwanted cutoffs of the lower bits, yielding 0 instead of 3 as object type intests/test_odb_backend.py.This PR works around the issue by parsing the type into a well-known integer type first, and then casting to the
git_object_tenum type, avoiding the undefined behavior.