diff -uNr rsync-3.1.3/configure.ac rsync-3.1.3.mod/configure.ac
--- rsync-3.1.3/configure.ac	2020-07-31 01:33:58.000000000 +0000
+++ rsync-3.1.3.mod/configure.ac	2021-04-11 01:45:27.000000000 +0000
@@ -380,7 +380,7 @@
 			# http://www.v6.linux.or.jp/
 			AC_EGREP_CPP(yes, [
 #include <features.h>
-#if defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1
+#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(__ANDROID__)
 yes
 #endif],
 				[ipv6type=$i;