1 files changed, 2 insertions, 0 deletions
diff --git a/vm_core.h b/vm_core.h
index f7e4c056cb..a02205a624 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -688,6 +688,8 @@ typedef struct {
     rb_block_t block;
 } rb_env_t;
 
+extern const rb_data_type_t ruby_binding_data_type;
+
 #define GetBindingPtr(obj, ptr) \
   GetCoreDataFromValue((obj), rb_binding_t, (ptr))