Changelog r18 beta2

Changelog

Report issues to GitHub.

For Android Studio issues, follow the docs on the Android Studio site.

Announcements

• GCC has been removed.

• LLD is now available for testing. AOSP is in the process of switching to using LLD by default and the NDK will follow (timeline unknown). Test LLD in your app by passing -fuse-ld=lld when linking.

• gnustl, gabi++, and stlport have been removed.

• Support for ICS (android-14 and android-15) has been removed. Apps using executables no longer need to provide both a PIE and non-PIE executable.

• The Play Store will require 64-bit support when uploading an APK beginning in August 2019. Start porting now to avoid surprises when the time comes. For more information, see this blog post.

Changes

• Updated Clang to build 4751641, based on r328903.
  • With Issue 573 fixed, -Oz is now the default optimization mode for thumb.
• Updated libc++ to revision r334917.
• Added support for clang-tidy to ndk-build.
  • Enable application-wide with APP_CLANG_TIDY := true, or per-module with LOCAL_CLANG_TIDY := true.
  • Pass specific clang-tidy flags such as -checks with APP_CLANG_TIDY_FLAGS or LOCAL_CLANG_TIDY_FLAGS.
  • As usual, module settings override application settings.
  • By default no flags are passed to clang-tidy, so only the checks enabled by default in clang-tidy will be enabled. View the default list with clang-tidy -list-checks.
  • By default clang-tidy warnings are not errors. This behavior can be changed with -warnings-as-errors=*.
• ndk-build can now generate a JSON Compilation Database.
  • Generate with either ndk-build compile_commands.json (does not build) or ndk-build GEN_COMPILE_COMMANDS_DB=true (builds and generates database).
• Issue 490: ndk-build and CMake now default to using NEON for ARM when targeting android-23 (Marshmallow) or newer.
  • If your minSdkVersion is below 23 or if you were already enabling NEON manually, this change does not affect you.
  • CPUs that do not support this feature are uncommon and new devices were not allowed to ship without it beginning in Marshmallow, but older devices that did not support NEON may have been upgraded to Marshmallow.
  • If you need to continue supporting these devices and have a minSdkVersion of 23 or higher, you can disable NEON explicitly by setting LOCAL_ARM_NEON := false in ndk-build or passing -DANDROID_ARM_NEON=false to CMake.
  • Alternatively, use the Play Console to blacklist CPUs without NEON to disallow your app from being installed on those devices.
• Added APP_STRIP_MODE and LOCAL_STRIP_MODE to ndk-build.
  • Allows the user to specify the strip mode used for their modules.
  • The option is passed directly to the strip command. See the strip documentation for details.
  • If set to "none", strip will not be run.
  • Defaults to "--strip-unneeded". This is the same behavior as previous NDKs.
  • LOCAL_STRIP_MODE always overrides APP_STRIP_MODE when set.
• Issue 749: The libc++_shared.so in the NDK is no longer stripped of debug info. Debugging libc++ is now possible. Gradle will still strip the library before packaging it in an APK.

Known Issues

• This is not intended to be a comprehensive list of all outstanding bugs.
• Issue 360: thread_local variables with non-trivial destructors will cause segfaults if the containing library is dlcloseed on devices running M or newer, or devices before M when using a static STL. The simple workaround is to not call dlclose.
• Issue 70838247: Gold emits broken debug information for AArch64. AArch64 still uses BFD by default.
• This version of the NDK is incompatible with the Android Gradle plugin version 3.0 or older. If you see an error like No toolchains found in the NDK toolchains folder for ABI with prefix: mips64el-linux-android, update your project file to use plugin version 3.1 or newer. You will also need to upgrade to Android Studio 3.1 or newer.