Merge branch 'bjorn/compiler/fix-invalid-orddict'

* bjorn/compiler/fix-invalid-orddict:
  v3_kernel: Keep orddicts sorted
  sys_core_fold: Ensure that orddict keys are unique

2 files changed, 28 insertions, 14 deletions

diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl
index cbf6e256f7..7acf08129a 100644
--- a/lib/compiler/src/sys_core_fold.erl
+++ b/lib/compiler/src/sys_core_fold.erl
@@ -1458,8 +1458,19 @@ sub_add_scope(Vs, #sub{s=Scope0}=Sub) ->
     Sub#sub{s=Scope}.
 
 sub_subst_scope(#sub{v=S0,s=Scope}=Sub) ->
-    S = [{-1,#c_var{name=Sv}} || Sv <- cerl_sets:to_list(Scope)]++S0,
-    Sub#sub{v=S}.
+    Initial = case S0 of
+                  [{NegInt,_}|_] when is_integer(NegInt), NegInt < 0 ->
+                      NegInt - 1;
+                  _ ->
+                      -1
+              end,
+    S = sub_subst_scope_1(cerl_sets:to_list(Scope), Initial, S0),
+    Sub#sub{v=orddict:from_list(S)}.
+
+%% The keys in an orddict must be unique. Make them so!
+sub_subst_scope_1([H|T], Key, Acc) ->
+    sub_subst_scope_1(T, Key-1, [{Key,#c_var{name=H}}|Acc]);
+sub_subst_scope_1([], _, Acc) -> Acc.
 
 sub_is_val(#c_var{name=V}, #sub{v=S,s=Scope}) ->
     %% When the bottleneck in sub_del_var/2 was eliminated, this
diff --git a/lib/compiler/src/v3_kernel.erl b/lib/compiler/src/v3_kernel.erl
index 004c609311..1fc05109c5 100644
--- a/lib/compiler/src/v3_kernel.erl
+++ b/lib/compiler/src/v3_kernel.erl
@@ -1313,23 +1313,26 @@ get_vsub(V, Vsub) ->
 set_vsub(V, S, Vsub) ->
     orddict:store(V, S, Vsub).
 
-subst_vsub(Key, New, [{K,Key}|Dict]) ->
+subst_vsub(Key, New, Vsub) ->
+    orddict:from_list(subst_vsub_1(Key, New, Vsub)).
+
+subst_vsub_1(Key, New, [{K,Key}|Dict]) ->
     %% Fold chained substitution.
-    [{K,New}|subst_vsub(Key, New, Dict)];
-subst_vsub(Key, New, [{K,_}|_]=Dict) when Key < K ->
+    [{K,New}|subst_vsub_1(Key, New, Dict)];
+subst_vsub_1(Key, New, [{K,_}|_]=Dict) when Key < K ->
     %% Insert the new substitution here, and continue
     %% look for chained substitutions.
-    [{Key,New}|subst_vsub_1(Key, New, Dict)];
-subst_vsub(Key, New, [{K,_}=E|Dict]) when Key > K ->
-    [E|subst_vsub(Key, New, Dict)];
-subst_vsub(Key, New, []) -> [{Key,New}].
+    [{Key,New}|subst_vsub_2(Key, New, Dict)];
+subst_vsub_1(Key, New, [{K,_}=E|Dict]) when Key > K ->
+    [E|subst_vsub_1(Key, New, Dict)];
+subst_vsub_1(Key, New, []) -> [{Key,New}].
 
-subst_vsub_1(V, S, [{K,V}|Dict]) ->
+subst_vsub_2(V, S, [{K,V}|Dict]) ->
     %% Fold chained substitution.
-    [{K,S}|subst_vsub_1(V, S, Dict)];
-subst_vsub_1(V, S, [E|Dict]) ->
-    [E|subst_vsub_1(V, S, Dict)];
-subst_vsub_1(_, _, []) -> [].
+    [{K,S}|subst_vsub_2(V, S, Dict)];
+subst_vsub_2(V, S, [E|Dict]) ->
+    [E|subst_vsub_2(V, S, Dict)];
+subst_vsub_2(_, _, []) -> [].
 
 get_fsub(F, A, Fsub) ->
     case orddict:find({F,A}, Fsub) of