NDK doesn't support thread_local variables which require destructors,
so on Android it should use __thread instead.
Observations:
* ProtoBuf and other libraries are not using thread_local on Android.
* In Tensorflow, there's a "thread_local" in code about CUDA,
which should be safe enough.
More discussions are on https://github.com/android-ndk/ndk/issues/360 .
PLATFORM_LDFLAGS=-pthread
MKDEP=${CC} -M -std=c++11
PLATFORM_C=../../platform/c++11/src/nsync_semaphore_mutex.cc \
- ../../platform/c++11/src/per_thread_waiter.cc \
+ ../../platform/posix/src/per_thread_waiter.c \
../../platform/c++11/src/yield.cc \
../../platform/c++11/src/time_rep_timespec.cc \
../../platform/c++11/src/nsync_panic.cc