Building the NDK

The latest version of this document is available at https://android.googlesource.com/platform/ndk/+/master/docs/Building.md.

Both Linux and Windows NDKs are built on Linux machines. Windows host binaries are cross-compiled with MinGW.

Building the NDK for Mac OS X requires at least 10.13.

Prerequisites

• AOSP NDK Repository

  • Check out the branch master-ndk. Do this in a new directory.

    repo init -u https://android.googlesource.com/platform/manifest \
        -b master-ndk
    
    # Googlers, follow http://go/repo-init/master-ndk (check the box for
    # AOSP, uncheck the box for the git superproject). At time of writing,
    # the correct invocation is:
    repo init -u \
        sso://android.git.corp.google.com/platform/manifest -b master-ndk
    

If you wish to rebuild a given release of the NDK, the release branches can also be checked out. They're named ndk-release-r${RELEASE} for newer releases, but ndk-r{RELEASE}-release for older releases. For example, to check out the r19 release branch, use the -b ndk-release-r19 flag instad of -b master-ndk.

Linux dependencies are listed in the Dockerfile. You can use docker to build the NDK:

docker build -t ndk-dev infra/docker
docker run -it -u $UID -v `realpath ..`:/src -w /src/ndk ndk-dev ./checkbuild.py

Building on Mac OS X has similar dependencies as Linux, but also requires Xcode.

Running tests requires that adb is in your PATH. This is provided as part of the Android SDK.

Build

For Linux or Darwin

$ python checkbuild.py

For Windows, from Linux

$ python checkbuild.py --system windows64

checkbuild.py will also build all of the NDK tests. This takes about 3x as long as building the NDK itself, so pass --no-build-tests to skip building the tests if you're iterating on build behavior or plan to rebuild only specific tests. Tests can be built later with python run_tests.py --rebuild.

Note: The NDK's build and test scripts are implemented in Python 3 (currently 3.9). checkbuild.py will use a prebuilt Python, but run_tests.py does not do this yet. run_tests.py also can be run outside of a complete development environment (as it is when it is run on Windows), so a Python 3.9 virtualenv is recommended.

Packaging

Packaging uses zip -9 so is extremely time consuming and disabled by default. Use the --package flag to force packaging locally. This is not required for local development and only needs to be used when testing packaging behavior.