---

yaml
---
r: 703
b: refs/heads/master
c: 264c765
h: refs/heads/master
i:
  701: af332ad
  699: bf0d6ca
  695: 64b9beb
  687: 187c175
  671: bb43bf5
  639: d9e1cf5
v: v3

Author: graydon

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 751a47cc5ac3223c3b592659937b485c56ab2644
+refs/heads/master: 264c7659318cdd9213fc499810ffca107e10ffb8

trunk/src/boot/me/semant.ml

@@ -2134,11 +2134,7 @@ and vec_sty (word_bits:Il.bits) : Il.scalar_ty =
   let ptr = Il.ScalarTy (Il.AddrTy Il.OpaqueTy) in
     Il.AddrTy (Il.StructTy [| word; word; word; ptr |])
 
-and referent_type
-    ?parent_tag:parent_tag
-    (cx:ctxt)
-    (t:Ast.ty)
-    : Il.referent_ty =
+and referent_type (cx:ctxt) (t:Ast.ty) : Il.referent_ty =
   let s t = Il.ScalarTy t in
   let v b = Il.ValTy b in
   let p t = Il.AddrTy t in
@@ -2153,7 +2149,12 @@ and referent_type
   let tag ttag =
     let n = get_n_tag_tups cx ttag in
     let union =
-      let rty t = referent_type ~parent_tag:ttag cx t in
+      let rty t =
+        match t with
+            Ast.TY_box (Ast.TY_tag dst_tag) when is_back_edge ttag dst_tag ->
+              sp (Il.StructTy [| word; Il.OpaqueTy |])
+          | _ -> referent_type cx t
+      in
       let tup ttup = Il.StructTy (Array.map rty ttup) in
         Array.init n (fun i -> tup (get_nth_tag_tup cx ttag i))
     in
@@ -2193,13 +2194,7 @@ and referent_type
       | Ast.TY_fn _ -> fn_rty cx false
       | Ast.TY_obj _ -> obj_rty word_bits
 
-      | Ast.TY_tag ttag ->
-          begin
-            match parent_tag with
-                Some parent_tag when is_back_edge ttag parent_tag ->
-                  Il.OpaqueTy
-              | _ -> tag ttag
-          end
+      | Ast.TY_tag ttag -> tag ttag
 
       | Ast.TY_chan _
       | Ast.TY_port _
@@ -2210,15 +2205,14 @@ and referent_type
       | Ast.TY_native _ -> ptr
 
       | Ast.TY_box t ->
-          sp (Il.StructTy
-            [| word; referent_type ?parent_tag:parent_tag cx t |])
+          sp (Il.StructTy [| word; referent_type cx t |])
 
-      | Ast.TY_mutable t -> referent_type ?parent_tag:parent_tag cx t
+      | Ast.TY_mutable t -> referent_type cx t
 
       | Ast.TY_param (i, _) -> Il.ParamTy i
 
       | Ast.TY_named _ -> bug () "named type in referent_type"
-      | Ast.TY_constrained (t, _) -> referent_type ?parent_tag:parent_tag cx t
+      | Ast.TY_constrained (t, _) -> referent_type cx t
 
 and slot_referent_type (cx:ctxt) (sl:Ast.slot) : Il.referent_ty =
   let s t = Il.ScalarTy t in

trunk/src/boot/me/type.ml

@@ -1010,7 +1010,7 @@ let populate_tag_graph_node (cx:Semant.ctxt) (id:Common.opaque_id) (n:int) =
       | Ast.TY_rec ty_rec ->
           Array.iter (fun (_, ty) -> add_ty ty) ty_rec
       | Ast.TY_fn ty_fn -> add_ty_fn ty_fn
-      | Ast.TY_chan ty | Ast.TY_port ty | Ast.TY_mutable ty
+      | Ast.TY_vec ty | Ast.TY_chan ty | Ast.TY_port ty | Ast.TY_mutable ty
           | Ast.TY_constrained (ty, _) -> add_ty ty
       | Ast.TY_obj (_, ty_fns) ->
           Hashtbl.iter (fun _ ty_fn -> add_ty_fn ty_fn) ty_fns