Comprehensive list of broken python3 recipes

[AndreMiras]

Just like it was done before for python2 and python3crystax, we need a list of broken python3 recipes #1402

[strubbi77]

sqlalchemy is broken with python 3.7.1

cwd is /home/strubbi77/.local/share/python-for-android/build/other_builds/sqlalchemy-python3-python3/armeabi-v7a__ndk_target_21/sqlalchemy

Traceback (most recent call last):
File "/usr/local/bin/p4a", line 10, in
sys.exit(main())
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/toolchain.py", line 1033, in main
ToolchainCL()
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/toolchain.py", line 553, in init
getattr(self, args.subparser_name.replace('-', '_'))(args)
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/toolchain.py", line 150, in wrapper_func
build_dist_from_args(ctx, dist, args)
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/toolchain.py", line 191, in build_dist_from_args
build_recipes(build_order, python_modules, ctx)
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/build.py", line 633, in build_recipes
recipe.build_arch(arch)
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/recipe.py", line 867, in build_arch
self.build_compiled_components(arch)
File "/usr/local/lib/python3.7/dist-packages/pythonforandroid/recipe.py", line 884, in build_compiled_components
build_dir = glob.glob('lib.*')[0]
IndexError: list index out of range

[RobertFlatt]

[Previously posted in #1576 , suggested more appropriate here]

I tried to build all the user modules for python3, kivy. Of course a successful
apk build does not necessarily imply the apk contents are correct!

The following dependencies are required in addition to those for a simple .py build
(for which I use https://groups.google.com/forum/#!topic/kivy-users/Lf4zlYmLVPo )
sudo apt-get install -y autoconf libtool cmake libffi-dev pkg-config

I use python-for-android (master, installed 1/12/2019)
I tested each with a placeholder main.py and:
p4a apk --requirements=<module>,python3,kivy --arch=armeabi-v7a --ndk_version 17c --android_api 28 --ndk-api 21

The following modules successfully build an apk:

['Pillow', 'audiostream', 'cffi', 'cryptography', 'enum34', 'ffmpeg',
'ffpyplayer_codecs', 'freetype', 'harfbuzz', 'idna', 'ipaddress', 'jedi',
'jpeg', 'leveldb', 'libcurl', 'libexpat', 'libffi', 'libiconv', 'libogg',
'libsecp256k1', 'libshine', 'libvorbis', 'libx264', 'libxml2', 'libxslt',
'lxml','numpy', 'openal','openssl', 'pbkdf2', 'png', 'pycparser',
'pycryptodome', 'pyjnius', 'pysdl2','requests', 'sdl2_image', 'sdl2_mixer',
'sdl2_ttf', 'six', 'snappy', 'spine','sqlite3']

BUT, of these, the following fail with error ".. _ctypes..""
if module order is changed --requirements=python3,kivy,<module>

['Pillow','cffi','cryptography','enum34','idna','ipaddress','pbkdf2',
'pycparser','pycryptodome','requests','spine']

Which confirms that order can be important.

The following do not build because they have no dependency on 'python3', but
do have a dependency on some combination of 'python2'/'hostpython2'/
'python3crystax'/'hostpython3'

['apsw','atom','babel','boost','cdecimal','cherrypy','coverage','cymunk',
'dateutil','decorator','doubleratchet','enaml','ethash','evdev','feedparser',
'gevent','gevent-websocket','greenlet','groestlcoin_hash','icu','ifaddrs',
'kiwisolver','libglob','libnacl','libpq','libsodium','libtorrent',
'libtribler','libzbar','libzmq','m2crypto','msgpack-python','netifaces',
'omemo','omemo-backend-signal','pil','preppy','psycopg2','pyaml','pyasnl',
'pycrypto','pyethereum','pyicu','pyleveldb','pymunk','pynacl','pyogg',
'pyopenal','pyopenssl','pyproj','pyrxp','pysha3','pyusb','pyyaml','pyzmq',
'regex','ruamel.yaml','scrypt','secp256k1','shapely','simple-crypt',
'sqlalchemy','storm','sympy','ujson','vispy','websocket-client','wsaccl',
'x3dh','xeddsa','zbar','zeroconf','zope','zope_interface']

The following does not build because of a dependency I can't identify:
['flask']
The following do not build because they have a dependency on 'kivy' !
['kivent_core','kivent_cymunk','kivent_particles','kivent_polygen']

The following does not build because:
'p4a.cmake': No such file or directory
['libmysqlclient']

The following does not build because of cmake errors
['opencv']

The following does not build because (seems strange):
crypt.h: No such file or directory
['reportlab']

The following does not build because has dependency on 'incremental', 'constantly'
['twisted']

The following does not build because NDK v18 needed
['vlc']

[RobertFlatt]

Next I looked in the .apk for .so files in addition to the default set of .so
I found that most builds silently create an incomplete apk in my setup (the NONE items below).
Silently, is to my mind an issue!
Just starting to dig through why the apks are missing extra .so

EDIT: some are in 'site-packages' directory, I was not looking there.

Pillow NONE
audiostream NONE
cffi _ctypes.cpython-37m.so
cryptography _ctypes.cpython-37m.so _hashlib.cpython-37m.so _ssl.cpython-37m.so
enum34 NONE
ffmpeg NONE
ffpyplayer_codecs NONE
freetype NONE
harfbuzz NONE
idna NONE
ipaddress NONE
jedi NONE
jpeg NONE
leveldb NONE
libcurl _hashlib.cpython-37m.so _ssl.cpython-37m.so
libexpat NONE
libffi _ctypes.cpython-37m.so
libiconv NONE
libogg NONE
libsecp256k1 NONE
libshine NONE
libvorbis FAIL
libx264 NONE
libxml2 NONE
libxslt NONE
lxml NONE
numpy NONE
openal NONE
openssl _hashlib.cpython-37m.so _ssl.cpython-37m.so
pbkdf2 NONE
png NONE
pycparser NONE
pycryptodome _ctypes.cpython-37m.so
pyjnius FAIL
pysdl2 NONE
requests NONE
sdl2_image NONE
sdl2_mixer NONE
sdl2_ttf NONE
snappy NONE
spine NONE
sqlite3 _sqlite3.cpython-37m.so

[RobertFlatt]

A little more detail....

Build environment:

sudo apt-get install -y autoconf libtool cmake libffi-dev pkg-config libjpeg9-dev python3-pil
Using python-for-android - master, installed 1/19/2019

.p4a

--dist_name=tstlib
--private .
--package=com.example.tstlib
--name Tstlib
--arch=armeabi-v7a
--sdk_dir /home/bobf/androidtools/sdk
--ndk_dir /home/bobf/androidtools/android-ndk-r17c
--ndk_version 17c
--android_api 28
--ndk-api 21
--version 0.0.0

Build command:
p4a apk --requirements=<module>,python3,kivy
Resulting module builds can be divided into four groups:

1. Modules that build and APK contains object files (complete set ?)
2. Modules that build and APK contains no extra files (silent fails)
3. Modules that do not build APK because of dependency on 'python2', etc.
4. Modules that do not build APK because of other dependency.

1. Contains object files:

['Pillow', 'audiostream', 'cffi', 'cryptography', 'enum34', 'ffmpeg',
'ffpyplayer_codecs', 'freetype', 'harfbuzz', 'idna', 'ipaddress', 'jedi',
'jpeg', 'leveldb', 'libcurl', 'libexpat', 'libffi', 'libiconv', 'libogg',
'libsecp256k1', 'libshine',  'libx264', 'libxml2', 'libxslt','pycrypto',
'lxml','netifaces','numpy', 'openal','openssl', 'pbkdf2', 'png', 'pycparser',
'pycryptodome', 'pyjnius','pymunk', 'pysdl2','reportlab','requests', 'sdl2_image',
'sdl2_mixer','sdl2_ttf', 'six', 'snappy', 'spine','sqlite3']

These respectively contain:

Pillow :
site-packages/PIL/_imaging.so
site-packages/PIL/_imagingft.so
site-packages/PIL/_imagingmath.so
site-packages/PIL/_imagingmorph.so
audiostream :
site-packages/audiostream/core.so
site-packages/audiostream/platform/plat_android.so
site-packages/audiostream/sources/puredata.so
site-packages/audiostream/sources/thread.so
site-packages/audiostream/sources/wave.so
cffi :
modules/_ctypes.cpython-37m.so
site-packages/_cffi_backend.so
cryptography :
modules/_ctypes.cpython-37m.so
modules/_hashlib.cpython-37m.so
modules/_ssl.cpython-37m.so
site-packages/cryptography/hazmat/bindings/_constant_time.so
site-packages/cryptography/hazmat/bindings/_openssl.so
site-packages/cryptography/hazmat/bindings/_padding.so
site-packages/_cffi_backend.so
libcurl :
modules/_hashlib.cpython-37m.so
modules/_ssl.cpython-37m.so
libffi :
modules/_ctypes.cpython-37m.so
lxml :
site-packages/lxml/builder.so
site-packages/lxml/etree.so
site-packages/lxml/html/clean.so
site-packages/lxml/html/diff.so
site-packages/lxml/objectify.so
site-packages/lxml/_elementpath.so
netifaces :
site-packages/netifaces.so
numpy :
site-packages/numpy/core/multiarray.so
site-packages/numpy/core/umath.so
site-packages/numpy/core/_dummy.so
site-packages/numpy/core/_multiarray_tests.so
site-packages/numpy/core/_operand_flag_tests.so
site-packages/numpy/core/_rational_tests.so
site-packages/numpy/core/_struct_ufunc_tests.so
site-packages/numpy/core/_umath_tests.so
site-packages/numpy/fft/fftpack_lite.so
site-packages/numpy/linalg/lapack_lite.so
site-packages/numpy/linalg/_umath_linalg.so
site-packages/numpy/random/mtrand.so
openssl :
modules/_hashlib.cpython-37m.so
modules/_ssl.cpython-37m.so
pycrypto :
modules/_hashlib.cpython-37m.so
modules/_ssl.cpython-37m.so
site-packages/Crypto/Cipher/_AES.so
site-packages/Crypto/Cipher/_ARC2.so
site-packages/Crypto/Cipher/_ARC4.so
site-packages/Crypto/Cipher/_Blowfish.so
site-packages/Crypto/Cipher/_CAST.so
site-packages/Crypto/Cipher/_DES.so
site-packages/Crypto/Cipher/_DES3.so
site-packages/Crypto/Cipher/_XOR.so
site-packages/Crypto/Hash/MD2.so
site-packages/Crypto/Hash/MD4.so
site-packages/Crypto/Hash/RIPEMD160.so
site-packages/Crypto/Hash/SHA224.so
site-packages/Crypto/Hash/SHA256.so
site-packages/Crypto/Hash/SHA384.so
site-packages/Crypto/Hash/SHA512.so
site-packages/Crypto/Util/cpuid.so
site-packages/Crypto/Util/galois.so
site-packages/Crypto/Util/strxor.so
site-packages/Crypto/Util/_counter.so
site-packages/netifaces.so
pycryptodome :
modules/_ctypes.cpython-37m.so
site-packages/Crypto/Cipher/_ARC4.so
site-packages/Crypto/Cipher/_chacha20.so
site-packages/Crypto/Cipher/_raw_aes.so
site-packages/Crypto/Cipher/_raw_arc2.so
site-packages/Crypto/Cipher/_raw_blowfish.so
site-packages/Crypto/Cipher/_raw_cast.so
site-packages/Crypto/Cipher/_raw_cbc.so
site-packages/Crypto/Cipher/_raw_cfb.so
site-packages/Crypto/Cipher/_raw_ctr.so
site-packages/Crypto/Cipher/_raw_des.so
site-packages/Crypto/Cipher/_raw_des3.so
site-packages/Crypto/Cipher/_raw_ecb.so
site-packages/Crypto/Cipher/_raw_ocb.so
site-packages/Crypto/Cipher/_raw_ofb.so
site-packages/Crypto/Cipher/_Salsa20.so
site-packages/Crypto/Hash/_BLAKE2b.so
site-packages/Crypto/Hash/_BLAKE2s.so
site-packages/Crypto/Hash/_keccak.so
site-packages/Crypto/Hash/_MD2.so
site-packages/Crypto/Hash/_MD4.so
site-packages/Crypto/Hash/_RIPEMD160.so
site-packages/Crypto/Hash/_SHA224.so
site-packages/Crypto/Hash/_SHA256.so
site-packages/Crypto/Hash/_SHA384.so
site-packages/Crypto/Hash/_SHA512.so
site-packages/Crypto/Protocol/_scrypt.so
site-packages/Crypto/Util/_cpuid.so
site-packages/Crypto/Util/_galois.so
site-packages/Crypto/Util/_strxor.so
site-packages/_cffi_backend.so
pymunk :
modules/_ctypes.cpython-37m.so
site-packages/pymunk/libchipmunk.so
site-packages/_cffi_backend.so
reportlab :
site-packages/numpy/core/multiarray.so
site-packages/numpy/core/umath.so
site-packages/numpy/core/_dummy.so
site-packages/numpy/core/_multiarray_tests.so
site-packages/numpy/core/_operand_flag_tests.so
site-packages/numpy/core/_rational_tests.so
site-packages/numpy/core/_struct_ufunc_tests.so
site-packages/numpy/core/_umath_tests.so
site-packages/numpy/fft/fftpack_lite.so
site-packages/numpy/linalg/lapack_lite.so
site-packages/numpy/linalg/_umath_linalg.so
site-packages/numpy/random/mtrand.so
site-packages/reportlab/graphics/_renderPM.so
site-packages/reportlab/lib/_rl_accel.so
spine :
site-packages/spine/animation/animation.so
site-packages/spine/animation/animationstate.so
site-packages/spine/animation/attachmenttimeline.so
site-packages/spine/animation/colortimeline.so
site-packages/spine/animation/curvetimeline.so
site-packages/spine/animation/drawordertimeline.so
site-packages/spine/animation/eventtimeline.so
site-packages/spine/animation/ffdtimeline.so
site-packages/spine/animation/flipxtimeline.so
site-packages/spine/animation/flipytimeline.so
site-packages/spine/animation/ikconstrainttimeline.so
site-packages/spine/animation/rotatetimeline.so
site-packages/spine/animation/scaletimeline.so
site-packages/spine/animation/timeline.so
site-packages/spine/animation/trackentry.so
site-packages/spine/animation/translatetimeline.so
site-packages/spine/attachment/attachment.so
site-packages/spine/attachment/boundingboxattachment.so
site-packages/spine/attachment/meshattachment.so
site-packages/spine/attachment/regionattachment.so
site-packages/spine/attachment/skinnedmeshattachment.so
site-packages/spine/bone.so
site-packages/spine/ikconstraint.so
site-packages/spine/skeleton/skeleton.so
site-packages/spine/skeleton/skeletonbounds.so
site-packages/spine/skeleton/skeletondata.so
site-packages/spine/slot.so
site-packages/spine/spineevent.so
site-packages/spine/utils.so
sqlite3 :
modules/_sqlite3.cpython-37m.so

2. Silent fails:

['enum34', 'ffmpeg', 'ffpyplayer_codecs', 'freetype', 'harfbuzz', 'idna', 'ipaddress', 'jedi', 'jpeg', 'leveldb', 'libexpat', 'libiconv', 'libogg', 'libsecp256k1', 'libshine', 'libx264', 'libxml2', 'libxslt', 'openal', 'pbkdf2', 'png', 'pycparser', 'pyjnius', 'pysdl2', 'requests', 'sdl2_image', 'sdl2_mixer', 'sdl2_ttf', 'six', 'snappy','zeroconf']

Lots of reasons here, not clear to me I can correctly diagnose, but I see things like:
enum34 bypasses build on python3 (this might be OK in this case?))
libshine builds .a but it is not copied for apk
libxml2 builds .al but not .a, then tries to copy .a for apk

3. Dependency is Python2, etc:

['apsw','atom','babel','boost','cdecimal','cherrypy','coverage','cymunk',
'dateutil','decorator','doubleratchet','enaml','ethash','evdev','feedparser',
'gevent','gevent-websocket','greenlet','groestlcoin_hash','icu','ifaddrs',
'kiwisolver','libglob','libnacl','libpq','libsodium','libtorrent',
'libtribler','libvorbis','libzbar','libzmq','m2crypto','msgpack-python',
'omemo','omemo-backend-signal','pil','preppy','psycopg2','pyaml','pyasnl',
'pyethereum','pyicu','pyleveldb','pynacl','pyogg',
'pyopenal','pyopenssl','pyproj','pyrxp','pysha3','pyusb','pyyaml','pyzmq',
'regex','ruamel.yaml','scrypt','secp256k1','shapely','simple-crypt',
'sqlalchemy','storm','sympy','ujson','vispy','websocket-client','wsaccl',
'x3dh','xeddsa','zbar','zope','zope_interface']

4. Other dependencies:

['flask','kivent_core','kivent_cymunk','kivent_particles','kivent_polygen',
'libmysqlclient','opencv','twisted','vlc']

Build Log Files:

log_no_object.zip
log_no_apk.zip
log_has_object.zip

[inclement]

There must be something extra going on here, your list of silent fails contains several modules that I build all the time and know to work. It's completely possible that there's some issue that causes them to not be built in some circumstances that don't match mine, which could well be a bug, but I also don't think I've ever seen other people hit issues with them.

I'm thinking in particular of sdl2_image, sdl2_mixer, sdl2_ttf and pyjnius, which are core Kivy dependencies and so included in almost every apk anyone has ever built with p4a (a bit less so recently :) ), though I'd also strongly expect jedi, six and pysdl2 to work.

I'll try to replicate your method at some point to see what happens.

I can confirm pysdl2, sdl2_image, sdl2_ttf, pyjnius, png if that's used through PIL (pretty sure it is), jpeg (again through PIL), and libxml2 (used through lxml/python-docx) work for me, as in I actually used them to do things on Android.

[inclement]

@Ham-Merhead You keep mentioning extra .so files, are you aware that several of these recipes are not expected to build include any? In particular, python modules like pysdl2 and jedi.

Also, none of your "Contains object files" examples mention the libs directory which is where the object files end up for most recipes (e.g. sdl2_image leads to libs/armeabi-v7a/libSDL2_image.so, and should be present in every APK as it's a dependency of Kivy). Are you actually checking in there?

[RobertFlatt]

@inclement
@Jonast
Thanks for your interest. I saw several people in the user group having
problems with requirements not working for them. Got interested in why that
would be, and how to explain to them what to do. Need all the insight I can get.

are you aware that several of these recipes are not expected to build include any?

Yes, I speculate on that for enum34 [stdlib contains enum, is that the same thing?],
and as JonasT points out pyjnius would be another case.

Where do I find that 'not expected' information?

And if a requirement doesn't add anything to the apk, is it a requirement?

libs/armeabi-v7a/libSDL2_image.so, ....Are you actually checking in there?

My editing error, those 3 ['sdl2_image', 'sdl2_mixer', 'sdl2_ttf']
are in both my 'contain object' and 'silent fail' lists.

I was not automatically looking in 'lib/armeabi-v7a', I've rerun the failed
tests, I currently use a conservative 'clean_all' between each test which means
this takes a while.
The additional test looks for case insensitive 'module_name' in lib.
This found new files in 6 cases, great, thank you for the suggestion.

leveldb :
./lib/armeabi-v7a/libleveldb.so
libexpat :
./lib/armeabi-v7a/libexpat.so
libiconv :
./lib/armeabi-v7a/libiconv.so
libogg :
./lib/armeabi-v7a/libogg.so
libsecp256k1 :
./lib/armeabi-v7a/libsecp256k1.so
openal :
./lib/armeabi-v7a/libopenal.so

Also I see 'ipaddress' is in stdlib, perhaps this is never a requirement?

png if that's used through PIL (pretty sure it is), jpeg (again through PIL)

Is 'PIL' built in? Where is it?
'Pillow' puts 'PIL' in site-packages, png and jpeg don't.

libxml2 (used through lxml/python-docx) work for me, as in I actually used them to do things on Android.

Yes, the best thing would be automated testing on Android; presumably via adb.
For me, for now, for automated testing, checking the apk contents is a
practical start point. And that 'not expected' information would improve the
test quality.

'libxml2' is really interesting, because init.py builds the '.la' but
not the '.a'. It then copies the '.a' it didn't build.....
Disclaimer: I'm not an expert on p4a, there could well be something I'm
missing.

            # Ensure we only build libxml2.la as if we do everything
            # we'll need the glob dependency which is a big headache
            shprint(sh.make, "libxml2.la", _env=env)

            shutil.copyfile('.libs/libxml2.a',
                            join(self.ctx.libs_dir, 'libxml2.a'))

The object files I still can't find are:

['enum34', 'ffmpeg', 'ffpyplayer_codecs', 'freetype', 'harfbuzz', 'idna',
'jedi', 'jpeg',  'libshine', 'libx264', 'libxml2', 'libxslt',  'pbkdf2',
'png', 'pycparser',  'pysdl2', 'requests', 'six', 'snappy','zeroconf']

EDIT: Update I just found the ffmpeg files in lib, but not named ffmpeg, no others with this issue.

Where do I find that 'not expected' information?

It needs to be hardcoded for each recipe, they all invoke different build systems so without knowing how it's supposed to looked like afterwards, there is no automated way to determine whether they would normally be expected to create native code, or python code, or whatever else.

And if a requirement doesn't add anything to the apk, is it a requirement?

That is a misunderstanding, they all add something to the apk. It's just not always native code (no .so file), but instead might be e.g. .pyo/.py files in the site packages folder

[RobertFlatt]

@Jonast Thanks for the help, I'm getting there slowly. Have found some .py and additional .so
Will update you guys as I figure out (or not) where things are.

The one that really bugs me is static libraries '.a'. I can see them (mostly) being built and copied
to 'self.ctx.libs_dir', but they don't make it into the apk. (with any extension). And I can't find any
bootstrap code that copies '.a'.

@Ham-Merhead regarding static libraries, that is normal/expected, since static libraries are by nature compiled statically into the app main binary. This means that 1. they are only useful with a compiler and not at runtime and hence the .a file is never standalone shipped in the apk, 2. during compilation it becomes part of the program binary instead which in practice should be libmain.so.

So the most direct effect without closer binary examination should only be that libmain.so becomes larger (gradually with any additionally used .a library) simply by how static linking works

Edit: also yes that means it is pretty much impossible to check them. I would just put these recipes on a separate list that can't be automatically verified. The only way to do it practically that I can think of is write a small test program that actually tries to use them and runs in an emulator as part of the test, but of course that would be a lot more effort than just peeking into the .apk

[RobertFlatt]

Thanks again.

@Ham-Merhead thanks for looking into this 👍 helping out with questions is the least I can do

[RobertFlatt]

@Jonast
@inclement
I need some suggestions, failing that I'm starting to think "bug rumor".
Maybe one of you could try to replicate with the example at end of this post.

These fail in Android with:
"ModuleNotFoundError: No module named 'name'"

['harfbuzz', 'jpeg', 'libshine', 'libx264', 'libxml2', 'libxslt', 'png', 'snappy']

With the exception of 'snappy' all build .a files.
I can find these in the build (see below) but nothing in the apk
(The size of libmain.so does not change)

~/.local/share/python-for-android>find . -name *harfbuzz.a
./build/libs_collections/freetype/libharfbuzz.a
./build/other_builds/harfbuzz/armeabi-v7a__ndk_target_21/harfbuzz/src/.libs/libharfbuzz.a

~/.local/share/python-for-android>find . -name *jpeg.a
./build/libs_collections/jpeg/libjpeg.a
./build/libs_collections/jpeg/libturbojpeg.a
./build/other_builds/jpeg/armeabi-v7a__ndk_target_21/jpeg/libjpeg.a
./build/other_builds/jpeg/armeabi-v7a__ndk_target_21/jpeg/libturbojpeg.a

~/.local/share/python-for-android>find . -name *libshine.a
./build/other_builds/libshine/armeabi-v7a__ndk_target_21/libshine/.libs/libshine.a
./build/other_builds/libshine/armeabi-v7a__ndk_target_21/libshine/lib/libshine.a

~/.local/share/python-for-android>find . -name *libx264.a
./build/other_builds/libx264/armeabi-v7a__ndk_target_21/libx264/lib/libx264.a
./build/other_builds/libx264/armeabi-v7a__ndk_target_21/libx264/libx264.a

~/.local/share/python-for-android>find . -name *libxml2.a
./build/libs_collections/libxml2/libxml2.a
./build/other_builds/libxml2/armeabi-v7a__ndk_target_21/libxml2/.libs/libxml2.a

~/.local/share/python-for-android>find . -name *libxslt.a
./build/libs_collections/libxslt/libxslt.a
./build/other_builds/libxslt/armeabi-v7a__ndk_target_21/libxslt/libxslt/.libs/libxslt.a

~/.local/share/python-for-android>find . -name *png.a
./build/other_builds/png/armeabi-v7a__ndk_target_21/png/obj/local/armeabi-v7a/libpng.a

Bug Rumor Example:

import libxml2
from kivy.app import App
from kivy.uix.label import Label
from kivy.graphics import Color, Rectangle
from kivy.core.window import Window

class Demo(App):
    def set_background_color(self):
        with self.label.canvas.before:
            Color(0.5, 0.0, 0.5)
            Rectangle(size=Window.size) 
       
    def on_start(self):
        pass

    def _resize_handler(self,obj,size):
        self.set_background_color()

    def build(self):
        Window.bind(size=self._resize_handler)
        self.label = Label(text = 'Greetings Earthlings')
        self.set_background_color()
        return self.label

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

.p4a

--dist_name=libxml2
--requirements=libxml2,python3,kivy
--private .
--package=com.example.tstlib
--name Tstlib
--arch=armeabi-v7a
--sdk_dir /home/bobf/androidtools/sdk
--ndk_dir /home/bobf/androidtools/android-ndk-r17c
--ndk_version 17c
--android_api 28
--ndk-api 21
--version 0.0.0