build fails with -DWITH_PYMALLOC_RADIX_TREE=0

[doko42]

Bug report

Bug description:

bpo-37448 added a radix tree based memory map, also allowing to disable it:

To disable the radix tree map, set a preprocessor flag as follows:
-DWITH_PYMALLOC_RADIX_TREE=0.

However building with that fails:

In file included from ../Include/internal/pycore_interp.h:31,
                 from ../Include/internal/pycore_runtime.h:18,
                 from ../Include/internal/pycore_pystate.h:11,
                 from ../Modules/_asynciomodule.c:7:
../Include/internal/pycore_obmalloc.h:668:28: error: field 'usage' has incomplete type
  668 |     struct _obmalloc_usage usage;
      |                            ^~~~~

CPython versions tested on:

3.12

Operating systems tested on:

Linux

Linked PRs

• gh-112867: fix for WITH_PYMALLOC_RADIX_TREE=0 #112885
• [3.12] gh-112867: fix for WITH_PYMALLOC_RADIX_TREE=0 (GH-112885) #113068

[doko42]

@ericsnowcurrently, this is probably not working since issue gh-81057

[doko42]

looks like guarding the usage struct member with the same preprocessor define allows the build to succeed and also pass tests

[hugovk]

The PR has been merged 👍

Can we close this issue, or is there more to do? Do we need backports to 3.12 or 3.11?

[nascheme]

It does not need a backport.

[nascheme]

I'm wrong, needs backport to 3.12.