Python.h missing on 3.9 and 3.10

[mkcms]

Description:
A few days ago my builds with Python 3.9 and 3.10 broke due to a missing Python.h include in one of the dependent packages that I build during the process. The same setup builds fine for 3.11, 3.12 and 3.13, and it used to work before that for 3.9 and 3.10 as well.

As far as I know, no changes were made to the dependent package.

Example failing job: https://github.com/mkcms/bdx/actions/runs/12715895623/job/35449032864

A successful build from a week ago: https://github.com/mkcms/bdx/actions/runs/12610330973/job/35144803933

Action version:
Latest master

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:

• 3.9
• 3.10

Repro steps:
Try to compile a C Python extension that uses Python.h header.

Expected behavior:
No error.

Actual behavior:
The Python.h header can't be found.

libtool: compile:  g++ -DHAVE_CONFIG_H -I. -I../../python3 -I.. -I/opt/hostedtoolcache/Python/3.10.15/x64/include/python3.10 -fno-strict-aliasing -Wall -Wno-unused -Wno-uninitialized -fvisibility=hidden -fvisibility-inlines-hidden -g -O2 -MT xapian_wrap.lo -MD -MP -MF .deps/xapian_wrap.Tpo -c ../../python3/xapian_wrap.cc  -fPIC -DPIC -o .libs/xapian_wrap.o
../../python3/xapian_wrap.cc:20:10: fatal error: Python.h: No such file or directory
   20 | #include <Python.h>

[priyagupta108]

Hi @mkcms 👋,
Thank you for your report. We'll investigate the issue and get back to you with the details!

[priyagupta108]

Hi @mkcms,
I have attempted to reproduce the issue by forking your repository and running the same setup with Python 3.9 and 3.10. In my case, I did not encounter the Python.h missing error.

It's possible that the issue might be caused by cached dependencies or artifacts. Could you try clearing the cache and see if that resolves the problem?

Additionally, to ensure you are using the latest updates, could you please check with the actions/setup-python@v5 tag instead of @master in your GitHub Actions workflow? 

Please let me know if this helps or if you have any other details that might be relevant.
Thank you.