Android support updates

[aaron-bray]

Updated NDK revision
Specified ARCH ABI
Add linker flags to support users of the android os log utility

[aaron-bray]

I would like to consider changing the folder names from android-arm and android-arm64 to android-armv7a and android-armv8a respectively, this properly reflects the architecture abi.

[aaron-bray]

Also, there are just a lot of extra configuring that users might want to do
I did it by manually modifying the Dockerfile (i.e. NDK_REVISION and NDK API)
I think we could support this only in the Toolchain file, generalizing the Dockerfile

• We no longer need to use the make_standalone_toolchain script
• We could use ENV variable to specify the toolchain compiler version to use

I actually did this by bypassing the provide cmake.sh script, and calling the /usr/bin/cmake executable directly with a -DCMAKE_TOOLCHAIN_FILE option that I created

There are a lot of specific compiler and linker options that one could use when compiling for specific android devices

• ex. -mcpu=cortex-a57+crypto

This could also lead to 1 android container (with defaults to armv8a)
And a Readme that explains how to edit the provided Toolchain file, and provide it in your build
(so you can change the arch abi, target api, and provide some device specific compiler options)

[thewtex]

@aaron-bray thanks!

[thewtex]

I would like to consider changing the folder names from android-arm and android-arm64 to android-armv7a and android-armv8a respectively, this properly reflects the architecture abi.

👍 good idea, could be added in follow-up PRs.

[thewtex]

Also, there are just a lot of extra configuring that users might want to do
I did it by manually modifying the Dockerfile (i.e. NDK_REVISION and NDK API)
I think we could support this only in the Toolchain file, generalizing the Dockerfile

* We no longer need to use the make_standalone_toolchain script

* We could use ENV variable to specify the toolchain compiler version to use

I actually did this by bypassing the provide cmake.sh script, and calling the /usr/bin/cmake executable directly with a -DCMAKE_TOOLCHAIN_FILE option that I created

There are a lot of specific compiler and linker options that one could use when compiling for specific android devices

* ex. -`mcpu=cortex-a57+crypto`

This could also lead to 1 android container (with defaults to armv8a)
And a Readme that explains how to edit the provided Toolchain file, and provide it in your build
(so you can change the arch abi, target api, and provide some device specific compiler options)

We can also pass Docker environmental variables and CMake -D configuration values via the dockcross invocation script, so we may want a combination of supporting these options and how they are specified in the Dockerfile, the toolchain file, and having them well described in the documentation.