Soft enable runtime cpu detect for armv7-android target, so that it
can be disabled and remove dependency on 'cpufeatures' lib.
Change the arm_cpu_caps implementation selection such that 'no rtcd' takes
precedence over system type.
Switch to use -mtune instead of -mcpu. NDK was complaining about
-mcpu=cortex-a8 conflicting with -march=armv7-a, not sure why.
Add a linker flag to fix some cortex-a8 bug, as suggested by NDK Dev
Guide.
Examples:
Configure for armv7+neon:
./configure --target=armv7-android-gcc \
--sdk-path=/path/to/android/ndk \
--disable-runtime-cpu-detect \
--enable-realtime-only \
--disable-unit-tests
...armv7 w/o neon:
./configure --target=armv7-android-gcc \
--sdk-path=/path/to/android/ndk \
--disable-runtime-cpu-detect \
--enable-realtime-only \
--disable-neon \
--cpu=cortex-a9 \
--disable-unit-tests
Change-Id: I37e2c0592745208979deec38f7658378d4bd6cfa