Document the NDK's built-in toolchain file.

The third-party toolchain file doesn't actually work with newer NDKs, and the one shipped with the NDK has fewer bugs. Change-Id: I59e1db393f0d66b186fb71590fab14db7faa0756 Reviewed-on: https://boringssl-review.googlesource.com/24165 Reviewed-by: Adam Langley <[email protected]>
aws · Dec 14, 2017 · 5288779 · 5288779
1 parent 4358f10
commit 5288779
Showing 1 changed file with 9 additions and 4 deletions.
diff --git a/BUILDING.md b/BUILDING.md
@@ -79,22 +79,27 @@ for other variables which may be used to configure the build.
 
 ### Building for Android
 
-It's possible to build BoringSSL with the Android NDK using CMake. This has
-been tested with version 10d of the NDK.
+It's possible to build BoringSSL with the Android NDK using CMake. Recent
+versions of the NDK include a CMake toolchain file which works with CMake 3.6.0
+or later. This has been tested with version r16b of the NDK.
 
 Unpack the Android NDK somewhere and export `ANDROID_NDK` to point to the
 directory. Then make a build directory as above and run CMake like this:
 
     cmake -DANDROID_ABI=armeabi-v7a \
-          -DCMAKE_TOOLCHAIN_FILE=../third_party/android-cmake/android.toolchain.cmake \
+          -DCMAKE_TOOLCHAIN_FILE=${ANDROID_NDK}/build/cmake/android.toolchain.cmake \
           -DANDROID_NATIVE_API_LEVEL=16 \
           -GNinja ..
 
 Once you've run that, Ninja should produce Android-compatible binaries.  You
 can replace `armeabi-v7a` in the above with `arm64-v8a` and use API level 21 or
 higher to build aarch64 binaries.
 
-For other options, see [android-cmake's documentation](./third_party/android-cmake/README.md).
+For older NDK versions, BoringSSL ships a third-party CMake toolchain file. Use
+`../third_party/android-cmake/android.toolchain.cmake` for
+`CMAKE_TOOLCHAIN_FILE` instead.
+
+For other options, see the documentation in the toolchain file.
 
 ### Building for iOS