-The tkill(2) function was removed from libc in NDK r11.
-
-diff -u -r ../bdwgc-c861ec3d1825b5bb450d20bf9091562fa8a81a4d/pthread_stop_world.c ./pthread_stop_world.c
---- ../bdwgc-c861ec3d1825b5bb450d20bf9091562fa8a81a4d/pthread_stop_world.c 2016-01-13 03:34:56.000000000 -0500
-+++ ./pthread_stop_world.c 2016-03-10 07:09:03.607785056 -0500
-@@ -450,7 +450,7 @@
- #endif
+diff -u -r ../gc-7.6.0/pthread_stop_world.c ./pthread_stop_world.c
+--- ../gc-7.6.0/pthread_stop_world.c 2016-08-02 15:36:14.000000000 -0400
++++ ./pthread_stop_world.c 2016-08-14 16:52:41.334806302 -0400
+@@ -365,7 +365,7 @@
+ }
- #ifdef USE_TKILL_ON_ANDROID
-- extern int tkill(pid_t tid, int sig); /* from sys/linux-unistd.h */
-+ static int tkill(pid_t tid, int sig) { return tgkill(-1, tid, sig); }
+ # ifdef USE_TKILL_ON_ANDROID
+- extern int tkill(pid_t tid, int sig); /* from sys/linux-unistd.h */
++ static int tkill(pid_t tid, int sig) { return tgkill(-1, tid, sig); }
- static int android_thread_kill(pid_t tid, int sig)
- {
+ static int android_thread_kill(pid_t tid, int sig)
+ {