[python3] cross compile python3 for android on linux

[Arlen-LT]

Fixed #30501

• Changes comply with the maintainer guide
• SHA512s are updated for each updated download
• The "supports" clause reflects platforms that may be fixed by this new version
• Any fixed CI baseline entries are removed from that file.
• Any patches that are no longer applied are deleted from the port's directory.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is added to each modified port's versions file.

Description

This PR primarily addresses the cross-compilation-for-android issue.

Changes Made

• Set appropriate compilation options for cross-compilation in the python3/portfile.cmake.

Validation

• This change will not affect existing builds for other platforms

[Arlen-LT]

@microsoft-github-policy-service agree

[dg0yt]

FTR #31621 is not dead. The work was put on hold by the pending update to python 3.11.

[dg0yt]

FTR there are also users who build for Android on Windows or macOS.

[MonicaLiu0311]

At present, the version information of your commit is inconsistent with your local one:

##[error]Found the following errors:
##[error]versions/p-/python3.json(2,): error : while parsing versions for python3 from version/p-/python3.json
Version 3.11.4#1 was not found in versions file for python3.

--overwrite-version
After the first modification, please run ./vcpkg x-add-version portName to generate the corresponding json; for subsequent modifications of the same version, please use ./vcpkg x-add-version portName --overwrite-version to update git-tree.

[MonicaLiu0311]

Note: I will be converting your PR to draft status. When you respond, please revert to "ready for review".

[dg0yt]

As commented before, this PR doesn't properly deal with triplets and toolchains.
Getting it right will throw you on the changes which I already have in #31621. (And in particular in #31228 - vcpkg maintainers, are you listening?)

Given that the python changes are expensive in vcpkg CI, I would really recommend alignment of these activities.

What I still might need to integrate is the INSTSONAME and ctypes changes. If these changes are needed, they should also be upstreamed.

[Arlen-LT]

As commented before, this PR doesn't properly deal with triplets and toolchains. Getting it right will throw you on the changes which I already have in #31621. (And in particular in #31228 - vcpkg maintainers, are you listening?)

Given that the python changes are expensive in vcpkg CI, I would really recommend alignment of these activities.

What I still might need to integrate is the INSTSONAME and ctypes changes. If these changes are needed, they should also be upstreamed.

Which you mentioned are all resolved, please review again. I have seen #31621, but I don't think they are conflict. I'm attemping to upstream the patches.

[Arlen-LT]

@MonicaLiu0311 @dg0yt Please approve this pull request

[Arlen-LT]

@LilyWangLL Could anybody merge this pr?

[dg0yt]

My position is unchanged:

• There is no need to limit cross builds to linux host.
• It is the wrong direction to handle compiler setup to specific portfiles when it should/could be fixed in vcpkg_configure_make.

But you will need wait for the vcpkg owners to decide.

[MonicaLiu0311]

Mark info:reviewed for further review.

[Arlen-LT]

My position is unchanged:

• There is no need to limit cross builds to linux host.
• It is the wrong direction to handle compiler setup to specific portfiles when the it should/could be fixed in vcpkg_configure_make.

But you will need wait for the vcpkg owners to decide.

I know your PR #31621 addresses the nature of cross-compile, however this PR is more inclined to aim at creating a python interpreter and binary artifact that meets runtime expectations on Android.
In addition, I found that if you only use the default clang without the architecture of the target android system and the Android API version, compiling Python_Module fails due to finding the header files on the host.
So, you can modify the cross-compiling settings for Mac or windows, but using Android NDK for building python3 is not just about cross-compiling problem. There is two fact:

1. Building python3 for Android never succeeds with current port, even without the commit updating from 3.10.7. At least on linux, this now can be addressed by this PR.
2. This PR won't affect any existing behavior that has been successfully built.

[dg0yt]

In addition, I found that if you only use the default clang without the architecture of the target android system and the Android API version, compiling Python_Module fails due to finding the header files on the host.

And consistently passing on the flags is the key contribution from #31621. It is not just a python3 or Android problem. Any workaround is technical debt.

And not supporting osx hosts immediately calls for the next PR. With a single line of change.

[MonicaLiu0311]

Please resolve the conflict.

[MonicaLiu0311]

Ping @Arlen-LT