diff --git a/script/apply.lean b/script/apply.lean
index 7ef01f106d..e072b45e1f 100644
--- a/script/apply.lean
+++ b/script/apply.lean
@@ -60,7 +60,7 @@ if (arity == fixed + {n}) \{
   for j in [n:max + 1] do
     let fs := mkFsArgs (j - n)
     let sep := if j = n then "" else ", "
-    emit s!"    case {j}: \{ obj* r = FN{j}(f)({fs}{sep}{args}); lean_free_small_object(f); return r; }\n"
+    emit s!"    case {j}: \{ obj* r = FN{j}(f)({fs}{sep}{args}); lean_free_object(f); return r; }\n"
   emit "    }
   }
   switch (arity) {\n"
@@ -162,7 +162,7 @@ static obj* fix_args(obj* f, unsigned n, obj*const* as) {
       for (unsigned i = 0; i < fixed; i++, source++, target++) {
           *target = *source;
       }
-      lean_free_small_object(f);
+      lean_free_object(f);
     }
     for (unsigned i = 0; i < n; i++, as++, target++) {
         *target = *as;
diff --git a/src/include/lean/lean.h b/src/include/lean/lean.h
index 644f684e24..5f967b0fdc 100644
--- a/src/include/lean/lean.h
+++ b/src/include/lean/lean.h
@@ -730,6 +730,14 @@ static inline void lean_closure_set(u_lean_obj_arg o, unsigned i, lean_obj_arg a
     assert(i < lean_closure_num_fixed(o));
     lean_to_closure(o)->m_objs[i] = a;
 }
+static inline size_t lean_closure_byte_size(lean_object * o) {
+    return sizeof(lean_closure_object) + sizeof(void*)*lean_closure_num_fixed(o);
+}
+
+static inline size_t lean_closure_data_byte_size(lean_object * o) {
+    // Matches for closures.
+    return lean_closure_byte_size(o);
+}
 
 LEAN_EXPORT lean_object* lean_apply_1(lean_object* f, lean_object* a1);
 LEAN_EXPORT lean_object* lean_apply_2(lean_object* f, lean_object* a1, lean_object* a2);
diff --git a/src/runtime/apply.cpp b/src/runtime/apply.cpp
index 96043510a3..cb24a9b364 100644
--- a/src/runtime/apply.cpp
+++ b/src/runtime/apply.cpp
@@ -29,7 +29,7 @@ static obj* fix_args(obj* f, unsigned n, obj*const* as) {
       for (unsigned i = 0; i < fixed; i++, source++, target++) {
           *target = *source;
       }
-      lean_free_small_object(f);
+      lean_free_object(f);
     }
     for (unsigned i = 0; i < n; i++, as++, target++) {
         *target = *as;
@@ -105,22 +105,22 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 1) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 1: { obj* r = FN1(f)(a1); lean_free_small_object(f); return r; }
-    case 2: { obj* r = FN2(f)(fx(0), a1); lean_free_small_object(f); return r; }
-    case 3: { obj* r = FN3(f)(fx(0), fx(1), a1); lean_free_small_object(f); return r; }
-    case 4: { obj* r = FN4(f)(fx(0), fx(1), fx(2), a1); lean_free_small_object(f); return r; }
-    case 5: { obj* r = FN5(f)(fx(0), fx(1), fx(2), fx(3), a1); lean_free_small_object(f); return r; }
-    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), a1); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), fx(14), a1); lean_free_small_object(f); return r; }
+    case 1: { obj* r = FN1(f)(a1); lean_free_object(f); return r; }
+    case 2: { obj* r = FN2(f)(fx(0), a1); lean_free_object(f); return r; }
+    case 3: { obj* r = FN3(f)(fx(0), fx(1), a1); lean_free_object(f); return r; }
+    case 4: { obj* r = FN4(f)(fx(0), fx(1), fx(2), a1); lean_free_object(f); return r; }
+    case 5: { obj* r = FN5(f)(fx(0), fx(1), fx(2), fx(3), a1); lean_free_object(f); return r; }
+    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), a1); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), fx(14), a1); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -164,21 +164,21 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 2) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 2: { obj* r = FN2(f)(a1, a2); lean_free_small_object(f); return r; }
-    case 3: { obj* r = FN3(f)(fx(0), a1, a2); lean_free_small_object(f); return r; }
-    case 4: { obj* r = FN4(f)(fx(0), fx(1), a1, a2); lean_free_small_object(f); return r; }
-    case 5: { obj* r = FN5(f)(fx(0), fx(1), fx(2), a1, a2); lean_free_small_object(f); return r; }
-    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), fx(3), a1, a2); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1, a2); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), a1, a2); lean_free_small_object(f); return r; }
+    case 2: { obj* r = FN2(f)(a1, a2); lean_free_object(f); return r; }
+    case 3: { obj* r = FN3(f)(fx(0), a1, a2); lean_free_object(f); return r; }
+    case 4: { obj* r = FN4(f)(fx(0), fx(1), a1, a2); lean_free_object(f); return r; }
+    case 5: { obj* r = FN5(f)(fx(0), fx(1), fx(2), a1, a2); lean_free_object(f); return r; }
+    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), fx(3), a1, a2); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1, a2); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), fx(13), a1, a2); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -226,20 +226,20 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 3) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 3: { obj* r = FN3(f)(a1, a2, a3); lean_free_small_object(f); return r; }
-    case 4: { obj* r = FN4(f)(fx(0), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 5: { obj* r = FN5(f)(fx(0), fx(1), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2, a3); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1, a2, a3); lean_free_small_object(f); return r; }
+    case 3: { obj* r = FN3(f)(a1, a2, a3); lean_free_object(f); return r; }
+    case 4: { obj* r = FN4(f)(fx(0), a1, a2, a3); lean_free_object(f); return r; }
+    case 5: { obj* r = FN5(f)(fx(0), fx(1), a1, a2, a3); lean_free_object(f); return r; }
+    case 6: { obj* r = FN6(f)(fx(0), fx(1), fx(2), a1, a2, a3); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2, a3); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), fx(12), a1, a2, a3); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -286,19 +286,19 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 4) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 4: { obj* r = FN4(f)(a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 5: { obj* r = FN5(f)(fx(0), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 6: { obj* r = FN6(f)(fx(0), fx(1), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3, a4); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2, a3, a4); lean_free_small_object(f); return r; }
+    case 4: { obj* r = FN4(f)(a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 5: { obj* r = FN5(f)(fx(0), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 6: { obj* r = FN6(f)(fx(0), fx(1), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3, a4); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), fx(11), a1, a2, a3, a4); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -344,18 +344,18 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 5) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 5: { obj* r = FN5(f)(a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 6: { obj* r = FN6(f)(fx(0), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), fx(1), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3, a4, a5); lean_free_small_object(f); return r; }
+    case 5: { obj* r = FN5(f)(a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 6: { obj* r = FN6(f)(fx(0), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), fx(1), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), fx(10), a1, a2, a3, a4, a5); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -400,17 +400,17 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 6) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 6: { obj* r = FN6(f)(a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 7: { obj* r = FN7(f)(fx(0), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4, a5, a6); lean_free_small_object(f); return r; }
+    case 6: { obj* r = FN6(f)(a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 7: { obj* r = FN7(f)(fx(0), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), fx(9), a1, a2, a3, a4, a5, a6); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -454,16 +454,16 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 7) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 7: { obj* r = FN7(f)(a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 8: { obj* r = FN8(f)(fx(0), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5, a6, a7); lean_free_small_object(f); return r; }
+    case 7: { obj* r = FN7(f)(a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 8: { obj* r = FN8(f)(fx(0), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), fx(8), a1, a2, a3, a4, a5, a6, a7); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -506,15 +506,15 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 8) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 8: { obj* r = FN8(f)(a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 9: { obj* r = FN9(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_small_object(f); return r; }
+    case 8: { obj* r = FN8(f)(a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 9: { obj* r = FN9(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), fx(7), a1, a2, a3, a4, a5, a6, a7, a8); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -556,14 +556,14 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 9) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 9: { obj* r = FN9(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 10: { obj* r = FN10(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_small_object(f); return r; }
+    case 9: { obj* r = FN9(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 10: { obj* r = FN10(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), fx(6), a1, a2, a3, a4, a5, a6, a7, a8, a9); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -604,13 +604,13 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 10) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 10: { obj* r = FN10(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 11: { obj* r = FN11(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_small_object(f); return r; }
+    case 10: { obj* r = FN10(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 11: { obj* r = FN11(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), fx(5), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -650,12 +650,12 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 11) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 11: { obj* r = FN11(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
-    case 12: { obj* r = FN12(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_small_object(f); return r; }
+    case 11: { obj* r = FN11(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
+    case 12: { obj* r = FN12(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), fx(4), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -694,11 +694,11 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 12) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 12: { obj* r = FN12(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_small_object(f); return r; }
-    case 13: { obj* r = FN13(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_small_object(f); return r; }
+    case 12: { obj* r = FN12(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_object(f); return r; }
+    case 13: { obj* r = FN13(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), fx(3), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -736,10 +736,10 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 13) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 13: { obj* r = FN13(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_small_object(f); return r; }
-    case 14: { obj* r = FN14(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_small_object(f); return r; }
+    case 13: { obj* r = FN13(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_object(f); return r; }
+    case 14: { obj* r = FN14(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), fx(2), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -776,9 +776,9 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 14) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 14: { obj* r = FN14(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_small_object(f); return r; }
-    case 15: { obj* r = FN15(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_small_object(f); return r; }
+    case 14: { obj* r = FN14(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_object(f); return r; }
+    case 15: { obj* r = FN15(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), fx(1), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -814,8 +814,8 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 15) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 15: { obj* r = FN15(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15); lean_free_small_object(f); return r; }
-    case 16: { obj* r = FN16(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15); lean_free_small_object(f); return r; }
+    case 15: { obj* r = FN15(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15); lean_free_object(f); return r; }
+    case 16: { obj* r = FN16(f)(fx(0), a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
@@ -850,7 +850,7 @@ unsigned fixed = lean_closure_num_fixed(f);
 if (arity == fixed + 16) {
   if (lean_is_exclusive(f)) {
     switch (arity) {
-    case 16: { obj* r = FN16(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16); lean_free_small_object(f); return r; }
+    case 16: { obj* r = FN16(f)(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16); lean_free_object(f); return r; }
     }
   }
   switch (arity) {
diff --git a/src/runtime/object.cpp b/src/runtime/object.cpp
index f595049f4a..c97ad33bb3 100644
--- a/src/runtime/object.cpp
+++ b/src/runtime/object.cpp
@@ -185,6 +185,7 @@ extern "C" LEAN_EXPORT size_t lean_object_byte_size(lean_object * o) {
         case LeanArray:       return lean_array_byte_size(o);
         case LeanScalarArray: return lean_sarray_byte_size(o);
         case LeanString:      return lean_string_byte_size(o);
+        case LeanClosure:     return lean_closure_byte_size(o);
         default:              return lean_small_object_size(o);
         }
     } else {
@@ -193,6 +194,7 @@ extern "C" LEAN_EXPORT size_t lean_object_byte_size(lean_object * o) {
         case LeanArray:       return lean_array_byte_size(o);
         case LeanScalarArray: return lean_sarray_byte_size(o);
         case LeanString:      return lean_string_byte_size(o);
+        case LeanClosure:     return lean_closure_byte_size(o);
         default:              return o->m_cs_sz;
         }
     }
@@ -207,6 +209,7 @@ extern "C" LEAN_EXPORT size_t lean_object_data_byte_size(lean_object * o) {
         case LeanArray:       return lean_array_data_byte_size(o);
         case LeanScalarArray: return lean_sarray_data_byte_size(o);
         case LeanString:      return lean_string_data_byte_size(o);
+        case LeanClosure:     return lean_closure_data_byte_size(o);
         default:              return lean_small_object_size(o);
         }
     } else {
@@ -215,6 +218,7 @@ extern "C" LEAN_EXPORT size_t lean_object_data_byte_size(lean_object * o) {
         case LeanArray:       return lean_array_data_byte_size(o);
         case LeanScalarArray: return lean_sarray_data_byte_size(o);
         case LeanString:      return lean_string_data_byte_size(o);
+        case LeanClosure:     return lean_closure_data_byte_size(o);
         default:              return o->m_cs_sz;
         }
     }
@@ -235,6 +239,7 @@ extern "C" LEAN_EXPORT void lean_free_object(lean_object * o) {
     case LeanArray:       return lean_dealloc(o, lean_array_byte_size(o));
     case LeanScalarArray: return lean_dealloc(o, lean_sarray_byte_size(o));
     case LeanString:      return lean_dealloc(o, lean_string_byte_size(o));
+    case LeanClosure:     return lean_dealloc(o, lean_closure_byte_size(o));
     case LeanMPZ:         to_mpz(o)->m_value.~mpz(); return lean_free_small_object(o);
     default:              return lean_free_small_object(o);
     }
@@ -335,7 +340,7 @@ static void lean_del_core(object * o, object * & todo) {
             object ** it  = lean_closure_arg_cptr(o);
             object ** end = it + lean_closure_num_fixed(o);
             for (; it != end; ++it) dec(*it, todo);
-            lean_free_small_object(o);
+            lean_dealloc(o, lean_closure_byte_size(o));
             break;
         }
         case LeanArray: {
diff --git a/stage0/src/stdlib_flags.h b/stage0/src/stdlib_flags.h
index 79a0e58edd..79b4b27c6c 100644
--- a/stage0/src/stdlib_flags.h
+++ b/stage0/src/stdlib_flags.h
@@ -1,5 +1,7 @@
 #include "util/options.h"
 
+// perform the update good sir
+
 namespace lean {
 options get_default_options() {
     options opts;