--- a/mcproxy/src/utils/mc_socket.cpp
+++ b/mcproxy/src/utils/mc_socket.cpp
@@ -38,6 +38,8 @@
 #include <unistd.h>
 
 #if !defined(__GLIBC__) || defined(__UCLIBC__)
+#define IP_MULTICAST_ALL 49
+
 #include "sourcefilter.cpp"
 #endif /* __GLIBC__ */