1 files changed, 1 insertions, 1 deletions
diff --git a/vm_core.h b/vm_core.h
index 69e9e1cd06..56879760fc 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -633,7 +633,7 @@ RUBY_EXTERN VALUE sysstack_error;
 /* for thread */
 
 #if RUBY_VM_THREAD_MODEL == 2
-extern rb_thread_t *ruby_current_thread;
+RUBY_EXTERN rb_thread_t *ruby_current_thread;
 extern rb_vm_t *ruby_current_vm;
 
 #define GET_VM() ruby_current_vm