Android NDK

This release of the NDK includes an important fix for Tegra2-based devices, and a few additional fixes and improvements:

Important bug fixes:

• Fixed GNU STL armeabi-v7a binaries to not crash on non-NEON devices. The files provided with NDK r7b were not configured properly, resulting in crashes on Tegra2-based devices and others when trying to use certain floating-point functions (e.g., cosf, sinf, expf).

Important changes:

• Added support for custom output directories through the NDK_OUT environment variable. When defined, this variable is used to store all intermediate generated files, instead of $PROJECT_PATH/obj. The variable is also recognized by ndk-gdb.
• Added support for building modules with hundreds or even thousands of source files by defining LOCAL_SHORT_COMMANDS to true in your Android.mk.

  This change forces the NDK build system to put most linker or archiver options into list files, as a work-around for command-line length limitations. See docs/ANDROID-MK.html for details.

Other bug fixes:

• Fixed android_getCpuCount() implementation in the cpufeatures helper library. On certain devices, where cores are enabled dynamically by the system, the previous implementation would report the total number of active cores the first time the function was called, rather than the total number of physically available cores.

This release of the NDK includes fixes for native Windows builds, Cygwin and many other improvements:

Important bug fixes:

• Updated sys/atomics.h to avoid correctness issues on some multi-core ARM-based devices. Rebuild your unmodified sources with this version of the NDK and this problem should be completely eliminated. For more details, read docs/ANDROID-ATOMICS.html.
• Reverted to binutils 2.19 to fix debugging issues that appeared in NDK r7 (which switched to binutils 2.20.1).
• Fixed ndk-build on 32-bit Linux. A packaging error put a 64-bit version of the awk executable under prebuilt/linux-x86/bin in NDK r7.
• Fixed native Windows build (ndk-build.cmd). Other build modes were not affected. The fixes include:
  • Removed an infinite loop / stack overflow bug that happened when trying to call ndk-build.cmd from a directory that was not the top of your project path (e.g., in any sub-directory of it).
  • Fixed a problem where the auto-generated dependency files were ignored. This meant that updating a header didn't trigger recompilation of sources that included it.
  • Fixed a problem where special characters in files or paths, other than spaces and quotes, were not correctly handled.
• Fixed the standalone toolchain to generate proper binaries when using -lstdc++ (i.e., linking against the GNU libstdc++ C++ runtime). You should use -lgnustl_shared if you want to link against the shared library version or -lstdc++ for the static version.

  See docs/STANDALONE-TOOLCHAIN.html for more details about this fix.

• Fixed gnustl_shared on Cygwin. The linker complained that it couldn't find libsupc++.a even though the file was at the right location.
• Fixed Cygwin C++ link when not using any specific C++ runtime through APP_STL.

Other changes:

• When your application uses the GNU libstdc++ runtime, the compiler will no longer forcibly enable exceptions and RTTI. This change results in smaller code.

  If you need these features, you must do one of the following:

  • Enable exceptions and/or RTTI explicitly in your modules or Application.mk. (recommended)
  • Define APP_GNUSTL_FORCE_CPP_FEATURES to 'exceptions', 'rtti' or both in your Application.mk. See docs/APPLICATION-MK.html for more details.
• ndk-gdb now works properly when your application has private services running in independent processes. It debugs the main application process, instead of the first process listed by ps, which is usually a service process.
• Fixed a rare bug where NDK r7 would fail to honor the LOCAL_ARM_MODE value and always compile certain source files (but not all) to 32-bit instructions.
• stlport: Refresh the sources to match the Android platform version. This update fixes a few minor bugs:
  • Fixed instantiation of an incomplete type
  • Fixed minor "==" versus "=" typo
  • Used memmove instead of memcpy in string::assign
  • Added better handling of IsNANorINF, IsINF, IsNegNAN, etc.

  For complete details, see the commit log.

• stlport: Removed 5 unnecessary static initializers from the library.
• The GNU libstdc++ libraries for armeabi-v7a were mistakenly compiled for armeabi instead. This change had no impact on correctness, but using the right ABI should provide slightly better performance.
• The cpu-features helper library was updated to report three optional x86 CPU features (SSSE3, MOVBE and POPCNT). See docs/CPU-FEATURES.html for more details.
• docs/NDK-BUILD.html was updated to mention NDK_APPLICATION_MK instead of NDK_APP_APPLICATION_MK to select a custom Application.mk file.
• Cygwin: ndk-build no longer creates an empty "NUL" file in the current directory when invoked.
• Cygwin: Added better automatic dependency detection. In the previous version, it didn't work properly in the following cases:
  • When the Cygwin drive prefix was not /cygdrive.
  • When using drive-less mounts, for example, when Cygwin would translate /home to \\server\subdir instead of C:\Some\Dir.
• Cygwin: ndk-build does not try to use the native Windows tools under $NDK/prebuilt/windows/bin with certain versions of Cygwin and/or GNU Make.

This release of the NDK includes new features to support the Android 4.0 platform as well as many other additions and improvements:

New features

• Added official NDK APIs for Android 4.0 (API level 14), which adds the following native features to the platform:
  • Added native multimedia API based on the Khronos Group OpenMAX AL? 1.0.1 standard. The new <OMXAL/OpenMAXAL.h> and <OMXAL/OpenMAXAL_Android.h> headers allow applications targeting API level 14 to perform multimedia output directly from native code by using a new Android-specific buffer queue interface. For more details, see docs/openmaxal/index.html and http://www.khronos.org/openmax/.
  • Updated the native audio API based on the Khronos Group OpenSL ES 1.0.1? standard. With API Level 14, you can now decode compressed audio (e.g. MP3, AAC, Vorbis) to PCM. For more details, see docs/opensles/index.html and http://www.khronos.org/opensles/.
• Added CCache support. To speed up large rebuilds, define the NDK_CCACHE environment variable to ccache (or the path to your ccache binary). When declared, the NDK build system automatically uses CCache when compiling any source file. For example:

  export NDK_CCACHE=ccache
  

  Note: CCache is not included in the NDK release so you must have it installed prior to using it. For more information about CCache, see http://ccache.samba.org.

• Added support for setting APP_ABI to all to indicate that you want to build your NDK modules for all the ABIs supported by your given NDK release. This means that either one of the following two lines in your Application.mk are equivalent with this release:

  APP_ABI := all
  APP_ABI := armeabi armeabi-v7a x86
  

  This also works if you define APP_ABI when calling ndk-build from the command-line, which is a quick way to check that your project builds for all supported ABIs without changing the project's Application.mk file. For example:

  ndk-build APP_ABI=all
  

• Added a LOCAL_CPP_FEATURES variable in Android.mk that allows you to declare which C++ features (RTTI or Exceptions) your module uses. This ensures that the final linking works correctly if you have prebuilt modules that depend on these features. See docs/ANDROID-MK.html and docs/CPLUSPLUS-SUPPORT.html for more details.
• Shortened paths to source and object files that are used in build commands. When invoking $NDK/ndk-build from your project path, the paths to the source, object, and binary files that are passed to the build commands are significantly shorter now, because they are passed relative to the current directory. This is useful when building projects with a lot of source files, to avoid limits on the maximum command line length supported by your host operating system. The behavior is unchanged if you invoke ndk-build from a sub-directory of your project tree, or if you define NDK_PROJECT_PATH to point to a specific directory.

Experimental features

You can now build your NDK source files on Windows without Cygwin by calling the ndk-build.cmd script from the command line from your project path. The script takes exactly the same arguments as the original ndk-build script. The Windows NDK package comes with its own prebuilt binaries for GNU Make, Awk and other tools required by the build. You should not need to install anything else to get a working build system.

Important: ndk-gdb does not work on Windows, so you still need Cygwin to debug.

This feature is still experimental, so feel free to try it and report issues on the public bug database or public forum. All samples and unit tests shipped with the NDK succesfully compile with this feature.

Important bug fixes

• Imported shared libraries are now installed by default to the target installation location (libs/<abi>) if APP_MODULES is not defined in your Application.mk. For example, if a top-level module foo imports a module bar, then both libfoo.so and libbar.so are copied to the install location. Previously, only libfoo.so was copied, unless you listed bar in your APP_MODULES too. If you define APP_MODULES explicitly, the behavior is unchanged.
• ndk-gdb now works correctly for activities with multiple categories in their MAIN intent filters.
• Static library imports are now properly transitive. For example, if a top-level module foo imports static library bar that imports static library zoo, the libfoo.so will now be linked against both libbar.a and libzoo.a.

Other changes

• docs/NATIVE-ACTIVITY.HTML: Fixed typo. The minimum API level should be 9, not 8 for native activities.
• docs/STABLE-APIS.html: Added missing documentation listing EGL as a supported stable API, starting from API level 9.
• download-toolchain-sources.sh: Updated to download the toolchain sources from android.googlesource.com, which is the new location for the AOSP servers.
• Added a new C++ support runtime named gabi++. More details about it are available in the updated docs/CPLUSPLUS-SUPPORT.html.
• Added a new C++ support runtime named gnustl_shared that corresponds to the shared library version of GNU libstdc++ v3 (GPLv3 license). See more info at docs/CPLUSPLUS-SUPPORT.html
• Added support for RTTI in the STLport C++ runtimes (no support for exceptions).
• Added support for multiple file extensions in LOCAL_CPP_EXTENSION. For example, to compile both foo.cpp and bar.cxx as C++ sources, declare the following:

  LOCAL_CPP_EXTENSION := .cpp .cxx
  

• Removed many unwanted exported symbols from the link-time shared system libraries provided by the NDK. This ensures that code generated with the standalone toolchain doesn't risk to accidentally depend on a non-stable ABI symbol (e.g. any libgcc.a symbol that changes each time the toolchain used to build the platform is changed)
• Refreshed the EGL and OpenGLES Khronos headers to support more extensions. Note that this does not change the NDK ABIs for the corresponding libraries, because each extension must be probed at runtime by the client application.

  The extensions that are available depend on your actual device and GPU drivers, not the platform version the device runs on. The header changes simply add new constants and types to make it easier to use the extensions when they have been probed with eglGetProcAddress() or glGetProcAddress(). The following list describes the newly supported extensions:

  GLES 1.x

  • GL_OES_vertex_array_object
  • GL_OES_EGL_image_external
  • GL_APPLE_texture_2D_limited_npot
  • GL_EXT_blend_minmax
  • GL_EXT_discard_framebuffer
  • GL_EXT_multi_draw_arrays
  • GL_EXT_read_format_bgra
  • GL_EXT_texture_filter_anisotropic
  • GL_EXT_texture_format_BGRA8888
  • GL_EXT_texture_lod_bias
  • GL_IMG_read_format
  • GL_IMG_texture_compression_pvrtc
  • GL_IMG_texture_env_enhanced_fixed_function
  • GL_IMG_user_clip_plane
  • GL_IMG_multisampled_render_to_texture
  • GL_NV_fence
  • GL_QCOM_driver_control
  • GL_QCOM_extended_get
  • GL_QCOM_extended_get2
  • GL_QCOM_perfmon_global_mode
  • GL_QCOM_writeonly_rendering
  • GL_QCOM_tiled_rendering

  GLES 2.0

  • GL_OES_element_index_uint
  • GL_OES_get_program_binary
  • GL_OES_mapbuffer
  • GL_OES_packed_depth_stencil
  • GL_OES_texture_3D
  • GL_OES_texture_float
  • GL_OES_texture_float_linear
  • GL_OES_texture_half_float_linear
  • GL_OES_texture_npot
  • GL_OES_vertex_array_object
  • GL_OES_EGL_image_external
  • GL_AMD_program_binary_Z400
  • GL_EXT_blend_minmax
  • GL_EXT_discard_framebuffer
  • GL_EXT_multi_draw_arrays
  • GL_EXT_read_format_bgra
  • GL_EXT_texture_format_BGRA8888
  • GL_EXT_texture_compression_dxt1
  • GL_IMG_program_binary
  • GL_IMG_read_format
  • GL_IMG_shader_binary
  • GL_IMG_texture_compression_pvrtc
  • GL_IMG_multisampled_render_to_texture
  • GL_NV_coverage_sample
  • GL_NV_depth_nonlinear
  • GL_QCOM_extended_get
  • GL_QCOM_extended_get2
  • GL_QCOM_writeonly_rendering
  • GL_QCOM_tiled_rendering

  EGL

  • EGL_ANDROID_recordable
  • EGL_NV_system_time

This release of the NDK does not include any new features compared to r6. The r6b release addresses the following issues in the r6 release:

Important bug fixes

• Fixed the build when APP_ABI="armeabi x86" is used for multi-architecture builds.
• Fixed the location of prebuilt STLport binaries in the NDK release package. A bug in the packaging script placed them in the wrong location.
• Fixed atexit() usage in shared libraries with the x86standalone toolchain.
• Fixed make-standalone-toolchain.sh --arch=x86. It used to fail to copy the proper GNU libstdc++ binaries to the right location.
• Fixed the standalone toolchain linker warnings about missing the definition and size for the __dso_handle symbol (ARM only).
• Fixed the inclusion order of $(SYSROOT)/usr/include for x86 builds. See the bug for more information.
• Fixed the definitions of ptrdiff_t and size_t in x86-specific systems when they are used with the x86 standalone toolchain.

This release of the NDK includes support for the x86 ABI and other minor changes. For detailed information describing the changes in this release, read the CHANGES.HTML document included in the NDK package.

General notes:

• Adds support for the x86 ABI, which allows you to generate machine code that runs on compatible x86-based Android devices. Major features for x86 include x86-specific toolchains, system headers, libraries and debugging support. For all of the details regarding x86 support, see docs/CPU-X86.html in the NDK package.

  By default, code is generated for ARM-based devices, but you can add x86 to your APP_ABI definition in your Application.mk file to build for x86 platforms. For example, the following line instructs ndk-build to build your code for three distinct ABIs:

  APP_ABI := armeabi armeabi-v7a x86

  Unless you rely on ARM-based assembly sources, you shouldn't need to touch your Android.mk files to build x86 machine code.

• You can build a standalone x86 toolchain using the --toolchain=x86-4.4.3 option when calling make-standalone-toolchain.sh. See docs/STANDALONE-TOOLCHAIN.html for more details.
• The new ndk-stack tool lets you translate stack traces in logcat that are generated by native code. The tool translates instruction addresses into a readable format that contains things such as the function, source file, and line number corresponding to each stack frame. For more information and a usage example, see docs/NDK-STACK.html.

Other changes:

arm-eabi-4.4.0, which had been deprecated since NDK r5, has been removed from the NDK distribution.

This release of the NDK does not include any new features compared to r5b. The r5c release addresses the following problems in the r5b release:

Important bug fixes:

• ndk-build: Fixed a rare bug that appeared when trying to perform parallel builds of debuggable projects.
• Fixed a typo that prevented LOCAL_WHOLE_STATIC_LIBRARIES to work correctly with the new toolchain and added documentation for this in docs/ANDROID-MK.html.
• Fixed a bug where code linked against gnustl_static crashed when run on platform releases older than API level 8 (Android 2.2).
• ndk-gdb: Fixed a bug that caused a segmentation fault when debugging Android 3.0 or newer devices.
• <android/input.h>: Two functions that were introduced in API level 9 (Android 2.3) were incorrect and are fixed. While this breaks the source API, the binary interface to the system is unchanged. The incorrect functions were missing a history_index parameter, and the correct definitions are shown below:

  float AMotionEvent_getHistoricalRawX(const AInputEvent* motion_event,
                                             size_t pointer_index,
                                             size_t history_index);
  
  float AMotionEvent_getHistoricalRawY(const AInputEvent* motion_event,
                                             size_t pointer_index,
                                             size_t history_index);
  

• Updated the C library ARM binary for API level 9 (Android 2.3) to correctly expose at link time new functions that were added in that API level (for example, pthread_rwlock_init).

Minor improvements and fixes:

• Object files are now always linked in the order they appear in LOCAL_SRC_FILES. This was not the case previously because the files were grouped by source extensions instead.
• When import-module fails, it now prints the list of directories that were searched. This is useful to check that the NDK_MODULE_PATH definition used by the build system is correct.
• When import-module succeeds, it now prints the directory where the module was found to the log (visible with NDK_LOG=1).
• Increased the build speed of debuggable applications when there is a very large number of include directories in the project.
• ndk-gdb: Better detection of adb shell failures and improved error messages.
• <pthread.h>: Fixed the definition of PTHREAD_RWLOCK_INITIALIZER for API level 9 (Android 2.3) and higher.
• Fixed an issue where a module could import itself, resulting in an infinite loop in GNU Make.
• Fixed a bug that caused the build to fail if LOCAL_ARM_NEON was set to true (typo in build/core/build-binary.mk).
• Fixed a bug that prevented the compilation of .s assembly files (.S files were okay).

This release of the NDK does not include any new features compared to r5. The r5b release addresses the following problems in the r5 release:

• The r5 binaries required glibc 2.11, but the r5b binaries are generated with a special toolchain that targets glibc 2.7 or higher instead. The Linux toolchain binaries now run on Ubuntu 8.04 or higher.
• Fixes a compiler bug in the arm-linux-androideabi-4.4.3 toolchain. The previous binary generated invalid thumb instruction sequences when dealing with signed chars.
• Adds missing documentation for the "gnustl_static" value for APP_STL, that allows you to link against a static library version of GNU libstdc++.
• The following ndk-build issues are fixed:
  • A bug that created inconsistent dependency files when a compilation error occured on Windows. This prevented a proper build after the error was fixed in the source code.
  • A Cygwin-specific bug where using very short paths for the Android NDK installation or the project path led to the generation of invalid dependency files. This made incremental builds impossible.
  • A typo that prevented the cpufeatures library from working correctly with the new NDK toolchain.
  • Builds in Cygwin are faster by avoiding calls to cygpath -m from GNU Make for every source or object file, which caused problems with very large source trees. In case this doesn't work properly, define NDK_USE_CYGPATH=1 in your environment to use cygpath -m again.
  • The Cygwin installation now notifies the user of invalid installation paths that contain spaces. Previously, an invalid path would output an error that complained about an incorrect version of GNU Make, even if the right one was installed.
• Fixed a typo that prevented the NDK_MODULE_PATH environment variable from working properly when it contained multiple directories separated with a colon.
• The prebuilt-common.sh script contains fixes to check the compiler for 64-bit generated machine code, instead of relying on the host tag, which allows the 32-bit toolchain to rebuild properly on Snow Leopard. The toolchain rebuild scripts now also support using a 32-bit host toolchain.
• A missing declaration for INET_ADDRSTRLEN was added to <netinet/in.h>.
• Missing declarations for IN6_IS_ADDR_MC_NODELOCAL and IN6_IS_ADDR_MC_GLOBAL were added to <netinet/in6.h>.
• 'asm' was replaced with '__asm__' in <asm/byteorder.h> to allow compilation with -std=c99.

This release of the NDK includes many new APIs, most of which are introduced to support the development of games and similar applications that make extensive use of native code. Using the APIs, developers have direct native access to events, audio, graphics and window management, assets, and storage. Developers can also implement the Android application lifecycle in native code with help from the new NativeActivity class. For detailed information describing the changes in this release, read the CHANGES.HTML document included in the downloaded NDK package.

General notes:

• Adds support for native activities, which allows you to implement the Android application lifecycle in native code.
• Adds native support for the following:
  • Input subsystem (such as the keyboard and touch screen)
  • Access to sensor data (accelerometer, compass, gyroscope, etc).
  • Event loop APIs to wait for things such as input and sensor events.
  • Window and surface subsystem
  • Audio APIs based on the OpenSL ES standard that support playback and recording as well as control over platform audio effects
  • Access to assets packaged in an .apk file.
• Includes a new toolchain (based on GCC 4.4.3), which generates better code, and can also now be used as a standalone cross-compiler, for people who want to build their stuff with ./configure && make. See docs/STANDALONE-TOOLCHAIN.html for the details. The binaries for GCC 4.4.0 are still provided, but the 4.2.1 binaries were removed.
• Adds support for prebuilt static and shared libraries (docs/PREBUILTS.html) and module exports and imports to make sharing and reuse of third-party modules much easier (docs/IMPORT-MODULE.html explains why).
• Provides a default C++ STL implementation (based on STLport) as a helper module. It can be used either as a static or shared library (details and usage examples are in sources/android/stlport/README). Prebuilt binaries for STLport (static or shared) and GNU libstdc++ (static only) are also provided if you choose to compile against those libraries instead of the default C++ STL implementation. C++ Exceptions and RTTI are not supported in the default STL implementation. For more information, see docs/CPLUSPLUS-SUPPORT.HTML.
• Includes improvements to the cpufeatures helper library that improves reporting of the CPU type (some devices previously reported ARMv7 CPU when the device really was an ARMv6). We recommend developers that use this library to rebuild their applications then upload to Google Play to benefit from the improvements.
• Adds an EGL library that lets you create and manage OpenGL ES textures and services.
• Adds new sample applications, native-plasma and native-activity, to demonstrate how to write a native activity.
• Includes many bugfixes and other small improvements; see docs/CHANGES.html for a more detailed list of changes.

NDK r4b notes:

Includes fixes for several issues in the NDK build and debugging scripts — if you are using NDK r4, we recommend downloading the NDK r4b build. For detailed information describing the changes in this release, read the CHANGES.TXT document included in the downloaded NDK package.

General notes:

• Provides a simplified build system through the new ndk-build build command.
• Adds support for easy native debugging of generated machine code on production devices through the new ndk-gdb command.
• Adds a new Android-specific ABI for ARM-based CPU architectures, armeabi-v7a. The new ABI extends the existing armeabi ABI to include these CPU instruction set extensions:
  • Thumb-2 instructions
  • VFP hardware FPU instructions (VFPv3-D16)
  • Optional support for ARM Advanced SIMD (NEON) GCC intrinsics and VFPv3-D32. Supported by devices such as Verizon Droid by Motorola, Google Nexus One, and others.
• Adds a new cpufeatures static library (with sources) that lets your app detect the host device's CPU features at runtime. Specifically, applications can check for ARMv7-A support, as well as VFPv3-D32 and NEON support, then provide separate code paths as needed.
• Adds a sample application, hello-neon, that illustrates how to use the cpufeatures library to check CPU features and then provide an optimized code path using NEON instrinsics, if supported by the CPU.
• Lets you generate machine code for either or both of the instruction sets supported by the NDK. For example, you can build for both ARMv5 and ARMv7-A architectures at the same time and have everything stored to your application's final .apk.
• To ensure that your applications are available to users only if their devices are capable of running them, Google Play now filters applications based on the instruction set information included in your application — no action is needed on your part to enable the filtering. Additionally, the Android system itself also checks your application at install time and allows the installation to continue only if the application provides a library that is compiled for the device's CPU architecture.
• Adds support for Android 2.2, including a new stable API for accessing the pixel buffers of Bitmap objects from native code.

General notes:

• Adds OpenGL ES 2.0 native library support.
• Adds a sample application,hello-gl2, that illustrates the use of OpenGL ES 2.0 vertex and fragment shaders.
• The toolchain binaries have been refreshed for this release with GCC 4.4.0, which should generate slightly more compact and efficient machine code than the previous one (4.2.1). The NDK also still provides the 4.2.1 binaries, which you can optionally use to build your machine code.

Originally released as "Android 1.6 NDK, Release 1".

General notes:

• Adds OpenGL ES 1.1 native library support.
• Adds a sample application, san-angeles, that renders 3D graphics through the native OpenGL ES APIs, while managing activity lifecycle with a GLSurfaceView object.

Originally released as "Android 1.5 NDK, Release 1".

General notes:

• Includes compiler support (GCC) for ARMv5TE instructions, including Thumb-1 instructions.
• Includes system headers for stable native APIs, documentation, and sample applications.