build openh264 for android under linux

Question

I'm trying to build openh264 to use on android

-I've the latest openh264 source from git

-I've ndk 17

-I'm using ubuntu 16.04

running

make OS=android NDKROOT=/home/r/aff/ndk TARGET=android-27 NDKLEVEL=27 sysroot=/home/r/aff/ndk/sysroot

I get the error:

r@r:~/aff/openh264$ make OS=android NDKROOT=/home/r/aff/ndk TARGET=android-27 NDKLEVEL=27 sysroot=/home/r/aff/ndk/sysroot/home/r/aff/ndk/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-gcc -O3 -DNDEBUG -DHAVE_NEON -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16 -DANDROID_NDK -fpic --sysroot=/home/r/aff/ndk/platforms/android-27/arch-arm -MMD -MP -DGENERATED_VERSION_HEADER -I./codec/api/svc -I./codec/common/inc -Icodec/common/inc -I/home/r/aff/ndk/sysroot -Dandroid_getCpuIdArm=wels_getCpuIdArm -Dandroid_setCpuArm=wels_setCpuArm -Dandroid_getCpuCount=wels_getCpuCount -Dandroid_getCpuFamily=wels_getCpuFamily -Dandroid_getCpuFeatures=wels_getCpuFeatures -Dandroid_setCpu=wels_setCpu  -I/home/r/aff/ndk/sources/android/cpufeatures -c -o codec/common/src/cpu-features.o /home/r/aff/ndk/sources/android/cpufeatures/cpu-features.c
In file included from /home/r/aff/ndk/sources/android/cpufeatures/cpu-features.c:64:0:
/home/r/aff/ndk/sources/android/cpufeatures/cpu-features.h:31:23: fatal error: sys/cdefs.h: No such file or directory
 #include <sys/cdefs.h>
                       ^
compilation terminated.
build/platform-android.mk:96: recipe for target 'codec/common/src/cpu-features.o' failed
make: *** [codec/common/src/cpu-features.o] Error 1

Answer 1

When in doubt, stop rolling your own build configurations and use a standalone toolchain (pay particular attention to the section at the bottom about "Building open source projects using standalone toolchains": https://developer.android.com/ndk/guides/standalone_toolchain

Answer 2

Changing from

TARGET=android-27 NDKLEVEL=27

to

TARGET=android-21 NDKLEVEL=21

solved this issue for me.