+Patch taken from https://gitweb.torproject.org/orbot.git/tree/external/libevent-patch-1
+For some reason arc4random_addrandom isn't present in 64-bit android archs. !
+
+--- ./configure.ac 2015-01-05 20:00:02.000000000 +0530
++++ ../configure.ac 2016-12-06 10:15:44.617028345 +0530
+@@ -290,7 +290,7 @@
+
+ dnl Checks for library functions.
+ AC_CHECK_FUNCS([gettimeofday vasprintf fcntl clock_gettime strtok_r strsep])
+-AC_CHECK_FUNCS([getnameinfo strlcpy inet_ntop inet_pton signal sigaction strtoll inet_aton pipe eventfd sendfile mmap splice arc4random arc4random_buf issetugid geteuid getegid getprotobynumber setenv unsetenv putenv sysctl])
++AC_CHECK_FUNCS([getnameinfo strlcpy inet_ntop inet_pton signal sigaction strtoll inet_aton pipe eventfd sendfile mmap splice arc4random arc4random_buf arc4random_addrandom issetugid geteuid getegid getprotobynumber setenv unsetenv putenv sysctl])
+ AC_CHECK_FUNCS([umask])
+
+ AC_CACHE_CHECK(
+--- ./evutil_rand.c 2013-11-01 23:48:57.000000000 +0530
++++ ../evutil_rand.c 2016-12-06 10:38:19.748912002 +0530
+@@ -174,7 +176,9 @@
+ void
+ evutil_secure_rng_add_bytes(const char *buf, size_t n)
+ {
++#ifdef _EVENT_HAVE_ARC4RANDOM_ADDRANDOM
+ arc4random_addrandom((unsigned char*)buf,
+ n>(size_t)INT_MAX ? INT_MAX : (int)n);
++#endif
+ }
+