diff --git a/src/external/libCuba/src/common/Fork.c b/src/external/libCuba/src/common/Fork.c
index 99605d25..82e21349 100644
--- a/src/external/libCuba/src/common/Fork.c
+++ b/src/external/libCuba/src/common/Fork.c
@@ -16,7 +16,7 @@
 
 #define MINCORES 1
 
-coreinit cubafun_;
+extern coreinit cubafun_;
 extern int cubaverb_;
 extern corespec cubaworkers_;