gh-131591: Fix GENERATE_DEBUG_SECTION for clangcl on Windows

[chris-eibl]

See #132098 where the discussion started.

I think this a skip news?

Maybe a skip issue, too? Unsure, whether to link with #131591.

• Issue: Implement PEP 768 – Safe external debugger interface for CPython #131591

[chris-eibl]

@Fidget-Spinner: clang-cl actually understands the __declspec and now we have the same section name without the . like for MSVC.

[chris-eibl]

Actually, this is the reason why clangcl failed with

error: symbol 'AsyncioDebug' is already defined

https://github.com/python/cpython/actions/runs/13288425017/job/37102791006#step:4:243

This also "syncs" with

cpython/Python/pylifecycle.c

Line 112 in ac14d4a

GENERATE_DEBUG_SECTION(PyRuntime, _PyRuntimeState _PyRuntime)

where _PyRuntime has a leading underscore, too.

[Fidget-Spinner]

We need a news entry please, because the debug section is now an externally facing thing. And we changed the name for _AsyncioDebug.

[chris-eibl]

The debug section name did not change, and the _AsyncioDebug is only an internal variable name?

Otherwise, the test cases would have failed - they only do the lookup per section name.

But sure, I can add a news entry. Can you suggest a wording?

[Fidget-Spinner]

The debug section name did not change, and the _AsyncioDebug is only an internal variable name?

Just to clarify: there are no changes to the name of the symbol in the binary? If there aren't any changes, we can skip the news entry.

[chris-eibl]

IMHO, the only change in the Windows clang-cl binary is, that now the PyRuntim and AsyncioD sections are emitted, like MSVC does. For all other platforms, nothing should have changed.

So I could mention something like "GENERATE_DEBUG_SECTION now emits the debug sections for clang-cl on Windows."

In case of Windows, the symbol names are in the pdb files, in case of Linux in the ELF files (unless stripped). I don't know whether this shall be mentioned, but strictly speaking - sure you are correct: the symbol name has changed.

Whether (and how spelled) that shall go into a news entry I am unsure about.

[Fidget-Spinner]

Ok if there's no change on existing platforms we can skip news.

[Fidget-Spinner]

Thanks!