Set explicit ctypes _layout_ in coff.py for Python 3.14#693
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Python 3.14 deprecates the implicit memory layout for ctypes Structures that set _pack_, requiring an explicit _layout_ (slated to become an error in 3.19). COFF is a Windows/MSVC format, and the implicit default has always been the MSVC layout, so set _layout_ = "ms" to preserve behavior and silence the warning. The attribute is ignored on Python 3.12/3.13, so older supported versions are unaffected. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Summary
Python 3.14 deprecates the implicit memory layout for
ctypesStructures that set_pack_, requiring an explicit_layout_. The implicit default is slated to become an error in Python 3.19.This produced:
COFF is a Windows/MSVC format, and the implicit default has always been the MSVC layout, so this sets
_layout_ = "ms"on the four affected structures (CoffFileHeader,CoffSectionTableEntry,CoffSymbolTableEntry,CoffRelocationTableEntry) to preserve behavior and silence the warning.Compatibility
_layout_is ignored as an unknown class attribute on Python 3.12/3.13, so the change is a no-op on older supported versions (requires-python = ">=3.12").Verification
Importing the module with
DeprecationWarningpromoted to an error no longer warns, and packed struct sizes are unchanged (20-byte header, 10-byte relocation entry).🤖 Generated with Claude Code