1 files changed, 4 insertions, 5 deletions
diff --git a/hv.h b/hv.h
index 163c660db6..b8d6b7d243 100644
--- a/hv.h
+++ b/hv.h
@@ -41,10 +41,9 @@ struct shared_he {
    Use the funcs in mro.c
 */
 
-typedef enum {
-    MRO_DFS, /* 0 */
-    MRO_C3   /* 1 */
-} mro_alg;
+
+/* structure may change, so not public yet */
+struct mro_alg;
 
 struct mro_meta {
     AV      *mro_linear_dfs; /* cached dfs @ISA linearization */
@@ -52,7 +51,7 @@ struct mro_meta {
     HV      *mro_nextmethod; /* next::method caching */
     U32     cache_gen;       /* Bumping this invalidates our method cache */
     U32     pkg_gen;         /* Bumps when local methods/@ISA change */
-    mro_alg mro_which;       /* which mro alg is in use? */
+    const struct mro_alg *mro_which; /* which mro alg is in use? */
 };
 
 /* Subject to change.