diff --git a/stage0/src/Lean/Elab/MutualDef.lean b/stage0/src/Lean/Elab/MutualDef.lean
index c124f55a84..d88923fdeb 100644
--- a/stage0/src/Lean/Elab/MutualDef.lean
+++ b/stage0/src/Lean/Elab/MutualDef.lean
@@ -102,9 +102,14 @@ private def elabHeaders (views : Array DefView) : TermElabM (Array DefViewElabHe
         elabBinders (catchAutoBoundImplicit := true) view.binders.getArgs fun xs => do
           let refForElabFunType := view.value
           elabFunType refForElabFunType xs view fun xs type => do
-            let type ← mkForallFVars (← read).autoBoundImplicits.toArray type
+            let mut type ← mkForallFVars (← read).autoBoundImplicits.toArray type
             let xs ← addAutoBoundImplicits xs
             let levelNames ← getLevelNames
+            if view.type?.isSome then
+              Term.synthesizeSyntheticMVarsNoPostponing
+              type ← instantiateMVars type
+              let pendingMVarIds ← getMVars type
+              discard <| logUnassignedUsingErrorInfos pendingMVarIds
             let newHeader := {
               ref           := view.ref,
               modifiers     := view.modifiers,
diff --git a/stage0/stdlib/Lean/Elab/MutualDef.c b/stage0/stdlib/Lean/Elab/MutualDef.c
index 75d8b03884..221d2461f2 100644
--- a/stage0/stdlib/Lean/Elab/MutualDef.c
+++ b/stage0/stdlib/Lean/Elab/MutualDef.c
@@ -47,7 +47,7 @@ lean_object* l_List_mapM___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_Mu
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_withFunLocalDecls_loop___rarg___lambda__1(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 extern lean_object* l_Lean_NameSet_instInhabitedNameSet;
 lean_object* l_Lean_Elab_Command_elabMutualDef(lean_object*, lean_object*, lean_object*, lean_object*);
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_Lean_Elab_Command_liftTermElabM___rarg(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_mkFreeVarMap(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_FixPoint_markModified(lean_object*);
@@ -283,7 +283,7 @@ lean_object* l_Lean_Elab_getDeclarationRange___at___private_Lean_Elab_MutualDef_
 lean_object* l_Lean_Elab_Term_MutualClosure_pushLetRecs___boxed(lean_object*, lean_object*, lean_object*, lean_object*);
 uint8_t l_Array_contains___at_Lean_Meta_CheckAssignment_check___spec__2(lean_object*, lean_object*);
 lean_object* l_Lean_Meta_lambdaTelescope___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_mkLetRecClosureFor___spec__2___rarg(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_checkModifiers___lambda__2(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_checkLetRecsToLiftTypes___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_Lean_Expr_collectMVars(lean_object*, lean_object*);
@@ -304,6 +304,7 @@ lean_object* l_Lean_Meta_lambdaTelescope___at___private_Lean_Elab_MutualDef_0__L
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check___lambda__6___closed__1;
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_getFunName_match__2___rarg(lean_object*, lean_object*, lean_object*);
 lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_mkInitialUsedFVarsMap___spec__3(lean_object*, lean_object*, lean_object*, size_t, size_t, lean_object*);
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_instInhabited___rarg(lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_instantiateMVarsAtHeader___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_List_forM___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_collectUsed___spec__1___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
@@ -444,6 +445,7 @@ lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean
 lean_object* l_Array_anyMUnsafe_any___at_Lean_Elab_Term_isAutoImplicit___spec__5___boxed(lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_Array_sequenceMap___at_myMacro____x40_Init_NotationExtra___hyg_2885____spec__1(lean_object*, lean_object*);
 lean_object* l_Lean_throwErrorAt___at_Lean_Elab_Command_elabMutualDef___spec__5(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__3(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_Lean_Elab_Term_MutualClosure_pushMain___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 uint8_t l_Std_PersistentArray_anyMAux___at_Lean_Elab_Term_isAutoImplicit___spec__2(lean_object*, lean_object*);
 lean_object* lean_expr_update_proj(lean_object*, lean_object*);
@@ -485,6 +487,7 @@ extern lean_object* l_myMacro____x40_Init_Notation___hyg_12458____closed__13;
 lean_object* l_Lean_Elab_Term_MutualClosure_Replacement_apply_match__1(lean_object*);
 lean_object* l_List_redLength___rarg(lean_object*);
 lean_object* l_Std_PersistentArray_push___rarg(lean_object*, lean_object*);
+lean_object* l_Lean_Meta_getMVars(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_withUsed_match__1(lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_mkClosureFor(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check___lambda__6(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
@@ -614,6 +617,7 @@ extern lean_object* l_Lean_myMacro____x40_Init_NotationExtra___hyg_1098____close
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_FixPoint_modifyUsedFVars___boxed(lean_object*, lean_object*, lean_object*);
 lean_object* l_Array_mapMUnsafe_map___at_Lean_Elab_Term_MutualClosure_main___spec__6(lean_object*, lean_object*, lean_object*, lean_object*, size_t, size_t, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check___lambda__3___closed__1;
+lean_object* l_Lean_Elab_Term_logUnassignedUsingErrorInfos(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
 uint8_t l_Lean_Syntax_isOfKind(lean_object*, lean_object*);
 lean_object* l_Array_mapMUnsafe_map___at_Lean_Elab_Term_MutualClosure_main___spec__7___boxed(lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* l_Lean_Elab_elabDeclAttrs___at_Lean_Elab_Command_elabMutualDef___spec__2(lean_object*, lean_object*, lean_object*, lean_object*);
@@ -675,7 +679,7 @@ uint8_t l_Lean_Elab_isFreshInstanceName(lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_checkModifiers___closed__3;
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_removeUnusedVars_match__1(lean_object*);
 lean_object* l_Lean_Elab_fixLevelParams(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1___boxed(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1___boxed(lean_object**);
 lean_object* l_List_forIn_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_MutualClosure_mkFreeVarMap___spec__4(lean_object*, lean_object*, lean_object*, lean_object*);
 lean_object* lean_expr_update_app(lean_object*, lean_object*, lean_object*);
 lean_object* l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check___lambda__3(lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*, lean_object*);
@@ -4404,7 +4408,73 @@ return x_24;
 }
 }
 }
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14, lean_object* x_15, lean_object* x_16) {
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14, lean_object* x_15, lean_object* x_16, lean_object* x_17, lean_object* x_18) {
+_start:
+{
+uint8_t x_19; lean_object* x_20; lean_object* x_21; lean_object* x_22; 
+x_19 = lean_ctor_get_uint8(x_1, sizeof(void*)*6);
+x_20 = lean_array_get_size(x_2);
+x_21 = lean_alloc_ctor(0, 8, 1);
+lean_ctor_set(x_21, 0, x_3);
+lean_ctor_set(x_21, 1, x_4);
+lean_ctor_set(x_21, 2, x_5);
+lean_ctor_set(x_21, 3, x_6);
+lean_ctor_set(x_21, 4, x_7);
+lean_ctor_set(x_21, 5, x_20);
+lean_ctor_set(x_21, 6, x_10);
+lean_ctor_set(x_21, 7, x_8);
+lean_ctor_set_uint8(x_21, sizeof(void*)*8, x_19);
+x_22 = l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check(x_9, x_21, x_12, x_13, x_14, x_15, x_16, x_17, x_18);
+if (lean_obj_tag(x_22) == 0)
+{
+uint8_t x_23; 
+x_23 = !lean_is_exclusive(x_22);
+if (x_23 == 0)
+{
+lean_object* x_24; 
+x_24 = lean_ctor_get(x_22, 0);
+lean_dec(x_24);
+lean_ctor_set(x_22, 0, x_21);
+return x_22;
+}
+else
+{
+lean_object* x_25; lean_object* x_26; 
+x_25 = lean_ctor_get(x_22, 1);
+lean_inc(x_25);
+lean_dec(x_22);
+x_26 = lean_alloc_ctor(0, 2, 0);
+lean_ctor_set(x_26, 0, x_21);
+lean_ctor_set(x_26, 1, x_25);
+return x_26;
+}
+}
+else
+{
+uint8_t x_27; 
+lean_dec(x_21);
+x_27 = !lean_is_exclusive(x_22);
+if (x_27 == 0)
+{
+return x_22;
+}
+else
+{
+lean_object* x_28; lean_object* x_29; lean_object* x_30; 
+x_28 = lean_ctor_get(x_22, 0);
+x_29 = lean_ctor_get(x_22, 1);
+lean_inc(x_29);
+lean_inc(x_28);
+lean_dec(x_22);
+x_30 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_30, 0, x_28);
+lean_ctor_set(x_30, 1, x_29);
+return x_30;
+}
+}
+}
+}
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14, lean_object* x_15, lean_object* x_16) {
 _start:
 {
 lean_object* x_17; lean_object* x_18; lean_object* x_19; 
@@ -4427,144 +4497,323 @@ lean_inc(x_10);
 x_22 = l_Lean_Elab_Term_addAutoBoundImplicits(x_8, x_10, x_11, x_12, x_13, x_14, x_15, x_21);
 if (lean_obj_tag(x_22) == 0)
 {
-lean_object* x_23; lean_object* x_24; lean_object* x_25; lean_object* x_26; lean_object* x_27; uint8_t x_28; lean_object* x_29; lean_object* x_30; lean_object* x_31; 
+lean_object* x_23; lean_object* x_24; lean_object* x_25; lean_object* x_26; 
 x_23 = lean_ctor_get(x_22, 0);
 lean_inc(x_23);
 x_24 = lean_ctor_get(x_22, 1);
 lean_inc(x_24);
 lean_dec(x_22);
 x_25 = l_Lean_Elab_Term_getLevelNames___rarg(x_11, x_12, x_13, x_14, x_15, x_24);
-x_26 = lean_ctor_get(x_25, 0);
-lean_inc(x_26);
-x_27 = lean_ctor_get(x_25, 1);
+x_26 = lean_ctor_get(x_1, 4);
+if (lean_obj_tag(x_26) == 0)
+{
+lean_object* x_27; lean_object* x_28; lean_object* x_29; lean_object* x_30; 
+x_27 = lean_ctor_get(x_25, 0);
 lean_inc(x_27);
+x_28 = lean_ctor_get(x_25, 1);
+lean_inc(x_28);
 lean_dec(x_25);
-x_28 = lean_ctor_get_uint8(x_1, sizeof(void*)*6);
-x_29 = lean_array_get_size(x_23);
+x_29 = lean_box(0);
+x_30 = l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(x_1, x_23, x_2, x_3, x_4, x_5, x_27, x_6, x_7, x_20, x_29, x_10, x_11, x_12, x_13, x_14, x_15, x_28);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
 lean_dec(x_23);
-x_30 = lean_alloc_ctor(0, 8, 1);
-lean_ctor_set(x_30, 0, x_2);
-lean_ctor_set(x_30, 1, x_3);
-lean_ctor_set(x_30, 2, x_4);
-lean_ctor_set(x_30, 3, x_5);
-lean_ctor_set(x_30, 4, x_26);
-lean_ctor_set(x_30, 5, x_29);
-lean_ctor_set(x_30, 6, x_20);
-lean_ctor_set(x_30, 7, x_6);
-lean_ctor_set_uint8(x_30, sizeof(void*)*8, x_28);
-x_31 = l___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_check(x_7, x_30, x_10, x_11, x_12, x_13, x_14, x_15, x_27);
-lean_dec(x_12);
-if (lean_obj_tag(x_31) == 0)
-{
-uint8_t x_32; 
-x_32 = !lean_is_exclusive(x_31);
-if (x_32 == 0)
-{
-lean_object* x_33; 
-x_33 = lean_ctor_get(x_31, 0);
-lean_dec(x_33);
-lean_ctor_set(x_31, 0, x_30);
-return x_31;
+return x_30;
 }
 else
 {
-lean_object* x_34; lean_object* x_35; 
-x_34 = lean_ctor_get(x_31, 1);
-lean_inc(x_34);
-lean_dec(x_31);
-x_35 = lean_alloc_ctor(0, 2, 0);
-lean_ctor_set(x_35, 0, x_30);
-lean_ctor_set(x_35, 1, x_34);
-return x_35;
-}
-}
-else
+lean_object* x_31; lean_object* x_32; uint8_t x_33; lean_object* x_34; lean_object* x_35; 
+x_31 = lean_ctor_get(x_25, 0);
+lean_inc(x_31);
+x_32 = lean_ctor_get(x_25, 1);
+lean_inc(x_32);
+lean_dec(x_25);
+x_33 = 0;
+x_34 = lean_box(0);
+lean_inc(x_15);
+lean_inc(x_14);
+lean_inc(x_13);
+lean_inc(x_12);
+lean_inc(x_11);
+lean_inc(x_10);
+x_35 = l_Lean_Elab_Term_synthesizeSyntheticMVars_loop(x_33, x_34, x_10, x_11, x_12, x_13, x_14, x_15, x_32);
+if (lean_obj_tag(x_35) == 0)
 {
-uint8_t x_36; 
-lean_dec(x_30);
-x_36 = !lean_is_exclusive(x_31);
-if (x_36 == 0)
+lean_object* x_36; lean_object* x_37; 
+x_36 = lean_ctor_get(x_35, 1);
+lean_inc(x_36);
+lean_dec(x_35);
+lean_inc(x_15);
+lean_inc(x_14);
+lean_inc(x_13);
+lean_inc(x_12);
+x_37 = l_Lean_Meta_instantiateMVars(x_20, x_12, x_13, x_14, x_15, x_36);
+if (lean_obj_tag(x_37) == 0)
 {
-return x_31;
-}
-else
-{
-lean_object* x_37; lean_object* x_38; lean_object* x_39; 
-x_37 = lean_ctor_get(x_31, 0);
-x_38 = lean_ctor_get(x_31, 1);
+lean_object* x_38; lean_object* x_39; lean_object* x_40; 
+x_38 = lean_ctor_get(x_37, 0);
 lean_inc(x_38);
-lean_inc(x_37);
-lean_dec(x_31);
-x_39 = lean_alloc_ctor(1, 2, 0);
-lean_ctor_set(x_39, 0, x_37);
-lean_ctor_set(x_39, 1, x_38);
-return x_39;
-}
-}
+x_39 = lean_ctor_get(x_37, 1);
+lean_inc(x_39);
+lean_dec(x_37);
+lean_inc(x_15);
+lean_inc(x_14);
+lean_inc(x_13);
+lean_inc(x_12);
+lean_inc(x_38);
+x_40 = l_Lean_Meta_getMVars(x_38, x_12, x_13, x_14, x_15, x_39);
+if (lean_obj_tag(x_40) == 0)
+{
+lean_object* x_41; lean_object* x_42; lean_object* x_43; 
+x_41 = lean_ctor_get(x_40, 0);
+lean_inc(x_41);
+x_42 = lean_ctor_get(x_40, 1);
+lean_inc(x_42);
+lean_dec(x_40);
+lean_inc(x_15);
+lean_inc(x_14);
+lean_inc(x_13);
+lean_inc(x_12);
+lean_inc(x_11);
+lean_inc(x_10);
+x_43 = l_Lean_Elab_Term_logUnassignedUsingErrorInfos(x_41, x_10, x_11, x_12, x_13, x_14, x_15, x_42);
+if (lean_obj_tag(x_43) == 0)
+{
+lean_object* x_44; lean_object* x_45; 
+x_44 = lean_ctor_get(x_43, 1);
+lean_inc(x_44);
+lean_dec(x_43);
+x_45 = l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(x_1, x_23, x_2, x_3, x_4, x_5, x_31, x_6, x_7, x_38, x_34, x_10, x_11, x_12, x_13, x_14, x_15, x_44);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
+lean_dec(x_23);
+return x_45;
 }
 else
 {
-uint8_t x_40; 
-lean_dec(x_20);
+uint8_t x_46; 
+lean_dec(x_38);
+lean_dec(x_31);
+lean_dec(x_23);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
 lean_dec(x_12);
+lean_dec(x_11);
 lean_dec(x_10);
 lean_dec(x_6);
 lean_dec(x_5);
 lean_dec(x_4);
 lean_dec(x_3);
 lean_dec(x_2);
-x_40 = !lean_is_exclusive(x_22);
-if (x_40 == 0)
+x_46 = !lean_is_exclusive(x_43);
+if (x_46 == 0)
+{
+return x_43;
+}
+else
+{
+lean_object* x_47; lean_object* x_48; lean_object* x_49; 
+x_47 = lean_ctor_get(x_43, 0);
+x_48 = lean_ctor_get(x_43, 1);
+lean_inc(x_48);
+lean_inc(x_47);
+lean_dec(x_43);
+x_49 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_49, 0, x_47);
+lean_ctor_set(x_49, 1, x_48);
+return x_49;
+}
+}
+}
+else
+{
+uint8_t x_50; 
+lean_dec(x_38);
+lean_dec(x_31);
+lean_dec(x_23);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
+lean_dec(x_10);
+lean_dec(x_6);
+lean_dec(x_5);
+lean_dec(x_4);
+lean_dec(x_3);
+lean_dec(x_2);
+x_50 = !lean_is_exclusive(x_40);
+if (x_50 == 0)
+{
+return x_40;
+}
+else
+{
+lean_object* x_51; lean_object* x_52; lean_object* x_53; 
+x_51 = lean_ctor_get(x_40, 0);
+x_52 = lean_ctor_get(x_40, 1);
+lean_inc(x_52);
+lean_inc(x_51);
+lean_dec(x_40);
+x_53 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_53, 0, x_51);
+lean_ctor_set(x_53, 1, x_52);
+return x_53;
+}
+}
+}
+else
+{
+uint8_t x_54; 
+lean_dec(x_31);
+lean_dec(x_23);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
+lean_dec(x_10);
+lean_dec(x_6);
+lean_dec(x_5);
+lean_dec(x_4);
+lean_dec(x_3);
+lean_dec(x_2);
+x_54 = !lean_is_exclusive(x_37);
+if (x_54 == 0)
+{
+return x_37;
+}
+else
+{
+lean_object* x_55; lean_object* x_56; lean_object* x_57; 
+x_55 = lean_ctor_get(x_37, 0);
+x_56 = lean_ctor_get(x_37, 1);
+lean_inc(x_56);
+lean_inc(x_55);
+lean_dec(x_37);
+x_57 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_57, 0, x_55);
+lean_ctor_set(x_57, 1, x_56);
+return x_57;
+}
+}
+}
+else
+{
+uint8_t x_58; 
+lean_dec(x_31);
+lean_dec(x_23);
+lean_dec(x_20);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
+lean_dec(x_10);
+lean_dec(x_6);
+lean_dec(x_5);
+lean_dec(x_4);
+lean_dec(x_3);
+lean_dec(x_2);
+x_58 = !lean_is_exclusive(x_35);
+if (x_58 == 0)
+{
+return x_35;
+}
+else
+{
+lean_object* x_59; lean_object* x_60; lean_object* x_61; 
+x_59 = lean_ctor_get(x_35, 0);
+x_60 = lean_ctor_get(x_35, 1);
+lean_inc(x_60);
+lean_inc(x_59);
+lean_dec(x_35);
+x_61 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_61, 0, x_59);
+lean_ctor_set(x_61, 1, x_60);
+return x_61;
+}
+}
+}
+}
+else
+{
+uint8_t x_62; 
+lean_dec(x_20);
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
+lean_dec(x_12);
+lean_dec(x_11);
+lean_dec(x_10);
+lean_dec(x_6);
+lean_dec(x_5);
+lean_dec(x_4);
+lean_dec(x_3);
+lean_dec(x_2);
+x_62 = !lean_is_exclusive(x_22);
+if (x_62 == 0)
 {
 return x_22;
 }
 else
 {
-lean_object* x_41; lean_object* x_42; lean_object* x_43; 
-x_41 = lean_ctor_get(x_22, 0);
-x_42 = lean_ctor_get(x_22, 1);
-lean_inc(x_42);
-lean_inc(x_41);
+lean_object* x_63; lean_object* x_64; lean_object* x_65; 
+x_63 = lean_ctor_get(x_22, 0);
+x_64 = lean_ctor_get(x_22, 1);
+lean_inc(x_64);
+lean_inc(x_63);
 lean_dec(x_22);
-x_43 = lean_alloc_ctor(1, 2, 0);
-lean_ctor_set(x_43, 0, x_41);
-lean_ctor_set(x_43, 1, x_42);
-return x_43;
+x_65 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_65, 0, x_63);
+lean_ctor_set(x_65, 1, x_64);
+return x_65;
 }
 }
 }
 else
 {
-uint8_t x_44; 
+uint8_t x_66; 
+lean_dec(x_15);
+lean_dec(x_14);
+lean_dec(x_13);
 lean_dec(x_12);
+lean_dec(x_11);
 lean_dec(x_10);
 lean_dec(x_6);
 lean_dec(x_5);
 lean_dec(x_4);
 lean_dec(x_3);
 lean_dec(x_2);
-x_44 = !lean_is_exclusive(x_19);
-if (x_44 == 0)
+x_66 = !lean_is_exclusive(x_19);
+if (x_66 == 0)
 {
 return x_19;
 }
 else
 {
-lean_object* x_45; lean_object* x_46; lean_object* x_47; 
-x_45 = lean_ctor_get(x_19, 0);
-x_46 = lean_ctor_get(x_19, 1);
-lean_inc(x_46);
-lean_inc(x_45);
+lean_object* x_67; lean_object* x_68; lean_object* x_69; 
+x_67 = lean_ctor_get(x_19, 0);
+x_68 = lean_ctor_get(x_19, 1);
+lean_inc(x_68);
+lean_inc(x_67);
 lean_dec(x_19);
-x_47 = lean_alloc_ctor(1, 2, 0);
-lean_ctor_set(x_47, 0, x_45);
-lean_ctor_set(x_47, 1, x_46);
-return x_47;
+x_69 = lean_alloc_ctor(1, 2, 0);
+lean_ctor_set(x_69, 0, x_67);
+lean_ctor_set(x_69, 1, x_68);
+return x_69;
 }
 }
 }
 }
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14) {
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__3(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14) {
 _start:
 {
 lean_object* x_15; lean_object* x_16; lean_object* x_17; 
@@ -4572,7 +4821,7 @@ x_15 = lean_ctor_get(x_1, 5);
 lean_inc(x_15);
 lean_inc(x_15);
 lean_inc(x_1);
-x_16 = lean_alloc_closure((void*)(l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1___boxed), 16, 7);
+x_16 = lean_alloc_closure((void*)(l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2___boxed), 16, 7);
 lean_closure_set(x_16, 0, x_1);
 lean_closure_set(x_16, 1, x_2);
 lean_closure_set(x_16, 2, x_3);
@@ -4688,7 +4937,7 @@ x_42 = l_Lean_Syntax_getArgs(x_41);
 lean_dec(x_41);
 lean_inc(x_4);
 lean_inc(x_33);
-x_43 = lean_alloc_closure((void*)(l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2), 14, 6);
+x_43 = lean_alloc_closure((void*)(l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__3), 14, 6);
 lean_closure_set(x_43, 0, x_14);
 lean_closure_set(x_43, 1, x_15);
 lean_closure_set(x_43, 2, x_28);
@@ -5157,15 +5406,46 @@ lean_dec(x_3);
 return x_10;
 }
 }
-lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1___boxed(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14, lean_object* x_15, lean_object* x_16) {
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1___boxed(lean_object** _args) {
+lean_object* x_1 = _args[0];
+lean_object* x_2 = _args[1];
+lean_object* x_3 = _args[2];
+lean_object* x_4 = _args[3];
+lean_object* x_5 = _args[4];
+lean_object* x_6 = _args[5];
+lean_object* x_7 = _args[6];
+lean_object* x_8 = _args[7];
+lean_object* x_9 = _args[8];
+lean_object* x_10 = _args[9];
+lean_object* x_11 = _args[10];
+lean_object* x_12 = _args[11];
+lean_object* x_13 = _args[12];
+lean_object* x_14 = _args[13];
+lean_object* x_15 = _args[14];
+lean_object* x_16 = _args[15];
+lean_object* x_17 = _args[16];
+lean_object* x_18 = _args[17];
 _start:
 {
-lean_object* x_17; 
-x_17 = l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(x_1, x_2, x_3, x_4, x_5, x_6, x_7, x_8, x_9, x_10, x_11, x_12, x_13, x_14, x_15, x_16);
+lean_object* x_19; 
+x_19 = l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__1(x_1, x_2, x_3, x_4, x_5, x_6, x_7, x_8, x_9, x_10, x_11, x_12, x_13, x_14, x_15, x_16, x_17, x_18);
+lean_dec(x_17);
+lean_dec(x_16);
 lean_dec(x_15);
 lean_dec(x_14);
 lean_dec(x_13);
 lean_dec(x_11);
+lean_dec(x_9);
+lean_dec(x_2);
+lean_dec(x_1);
+return x_19;
+}
+}
+lean_object* l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2___boxed(lean_object* x_1, lean_object* x_2, lean_object* x_3, lean_object* x_4, lean_object* x_5, lean_object* x_6, lean_object* x_7, lean_object* x_8, lean_object* x_9, lean_object* x_10, lean_object* x_11, lean_object* x_12, lean_object* x_13, lean_object* x_14, lean_object* x_15, lean_object* x_16) {
+_start:
+{
+lean_object* x_17; 
+x_17 = l_Array_forInUnsafe_loop___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_elabHeaders___spec__15___lambda__2(x_1, x_2, x_3, x_4, x_5, x_6, x_7, x_8, x_9, x_10, x_11, x_12, x_13, x_14, x_15, x_16);
 lean_dec(x_8);
 lean_dec(x_7);
 lean_dec(x_1);
@@ -5389,7 +5669,7 @@ _start:
 lean_object* x_1; lean_object* x_2; lean_object* x_3; lean_object* x_4; lean_object* x_5; lean_object* x_6; 
 x_1 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__1;
 x_2 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__2;
-x_3 = lean_unsigned_to_nat(139u);
+x_3 = lean_unsigned_to_nat(144u);
 x_4 = lean_unsigned_to_nat(43u);
 x_5 = l_Lean_Syntax_strLitToAtom___closed__3;
 x_6 = l___private_Init_Util_0__mkPanicMessageWithDecl(x_1, x_2, x_3, x_4, x_5);
@@ -6075,7 +6355,7 @@ _start:
 lean_object* x_1; lean_object* x_2; lean_object* x_3; lean_object* x_4; lean_object* x_5; lean_object* x_6; 
 x_1 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__1;
 x_2 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__2;
-x_3 = lean_unsigned_to_nat(147u);
+x_3 = lean_unsigned_to_nat(152u);
 x_4 = lean_unsigned_to_nat(13u);
 x_5 = l_Lean_Syntax_strLitToAtom___closed__3;
 x_6 = l___private_Init_Util_0__mkPanicMessageWithDecl(x_1, x_2, x_3, x_4, x_5);
@@ -6512,7 +6792,7 @@ _start:
 lean_object* x_1; lean_object* x_2; lean_object* x_3; lean_object* x_4; lean_object* x_5; lean_object* x_6; 
 x_1 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__1;
 x_2 = l_Array_mapMUnsafe_map___at___private_Lean_Elab_MutualDef_0__Lean_Elab_Term_expandWhereDeclsAsStructInst___spec__1___lambda__1___closed__2;
-x_3 = lean_unsigned_to_nat(149u);
+x_3 = lean_unsigned_to_nat(154u);
 x_4 = lean_unsigned_to_nat(9u);
 x_5 = l_Lean_Syntax_strLitToAtom___closed__3;
 x_6 = l___private_Init_Util_0__mkPanicMessageWithDecl(x_1, x_2, x_3, x_4, x_5);