Fix kiwisolver recipe fatal error: 'Python.h' file not found

[mriscoc]

From #3115: Fixes the problem with the KiwiSolver recipe in the current develop branch of pythonforandroid.

Error to fix:

[DEBUG]:        running build_ext
[DEBUG]:        building 'kiwisolver._cext' extension
[DEBUG]:        creating build/temp.linux-x86_64-cpython-311/py/src
...
[DEBUG]:        In file included from py/src/constraint.cpp:10:
[DEBUG]:        In file included from /tmp/build-env-lzty91e_/lib/python3.11/site-packages/cppy/include/cppy/cppy.h:16:
[DEBUG]:        /tmp/build-env-lzty91e_/lib/python3.11/site-packages/cppy/include/cppy/defines.h:10:10: fatal error: 'Python.h' file not found
[DEBUG]:        #include <Python.h>
[DEBUG]:                 ^~~~~~~~~~
[DEBUG]:        1 error generated.
[DEBUG]:        error: command '/usr/bin/ccache' failed with exit code 1
[DEBUG]:   
[DEBUG]:        ERROR Backend subprocess exited when trying to invoke build_wheel

buildozer.spec:

requirements = python3,kivy,kiwisolver
android.archs = arm64-v8a
p4a.branch = develop
log_level = 2

Minimal test:

import kivy

from kivy.app import App
from kivy.uix.button import Button
from kiwisolver import Variable, Solver

def callback(instance):
  x1 = Variable('x1')
  x2 = Variable('x2')
  xm = Variable('xm')
  constraints = [x1 >= 0, x2 <= 100, x2 >= x1 + 10, xm == (x1 + x2) / 2]
  solver = Solver()
  for cn in constraints:
    solver.addConstraint(cn)
  solver.addEditVariable(xm, 'strong')
  solver.suggestValue(xm, 60)
  solver.updateVariables()
  print(f"xm = {xm.value()}, x1 = {x1.value()}, x2 = {x2.value()}")


class MyApp(App):
  def build(self):
    btn1 = Button(text='Kiwisolver demo', size=(100, 50))
    btn1.bind(on_press=callback)
    return btn1

if __name__ == '__main__':
    MyApp().run()

[AndreMiras]

Thanks for the pull request @mriscoc
CI was failing and was fixed in #3119
Do you mind rebasing to develop, so that the CI runs on your PR.
Assuming you named the remote "upstream" you can use this command:

git pull --rebase upstream develop
git push -f

[AndreMiras]

Thanks, I guess a git pull does the job too, I can always squash/rebase upon merging.
Ubuntu tests are passing, but not macOS ones, do you have an idea why?
I'll try to build prior the change to simply make sure it's not a regression and we're good for a merge.

[mriscoc]

Thanks, I guess a git pull does the job too, I can always squash/rebase upon merging. Ubuntu tests are passing, but not macOS ones, do you have an idea why? I'll try to build prior the change to simply make sure it's not a regression and we're good for a merge.

Sorry, I don't know why it doesn't work on MacOS, it also fails on kiwisolver, maybe something to do with the compiler?

[AndreMiras]

Sorry, I don't know why it doesn't work on MacOS, it also fails on kiwisolver, maybe something to do with the compiler?

Yeah I haven't dug too much into it, but I tried to build it from develop and on macos-13 (not 14) and it's also not building, so I'll assume this isn't a regression from your PR. I'm good with merging, thanks again

[AndreMiras]

LGTM, thanks you all for looking this up

[AndreMiras]

@mriscoc I'm seeing this late, but why didn't we append the flags rather than overriding?

[T-Dynamos]

Ah yes, that might be the reason macos runner might be failing. (Btw I am to blame for this)

[AndreMiras]

Well the recipe wasn't building anyway, so overall situation is better than the previous state.