diff --git a/src/interpreter.c b/src/interpreter.c
index d006b5496e250..7d3a4504ecc5a 100644
--- a/src/interpreter.c
+++ b/src/interpreter.c
@@ -102,6 +102,23 @@ static void check_can_assign_type(jl_binding_t *b)
                   jl_symbol_name(b->name));
 }
 
+void jl_reinstantiate_inner_types(jl_datatype_t *t);
+
+void jl_set_datatype_super(jl_datatype_t *tt, jl_value_t *super)
+{
+    if (!jl_is_datatype(super) || !jl_is_abstracttype(super) ||
+        tt->name == ((jl_datatype_t*)super)->name ||
+        jl_subtype(super,(jl_value_t*)jl_vararg_type,0) ||
+        jl_is_tuple_type(super) ||
+        jl_subtype(super,(jl_value_t*)jl_type_type,0) ||
+        super == (jl_value_t*)jl_builtin_type) {
+        jl_errorf("invalid subtyping in definition of %s",
+                  jl_symbol_name(tt->name->name));
+    }
+    tt->super = (jl_datatype_t*)super;
+    jl_gc_wb(tt, tt->super);
+}
+
 static jl_value_t *eval(jl_value_t *e, jl_value_t **locals, size_t nl, size_t ngensym)
 {
     if (jl_is_symbol(e)) {
@@ -295,6 +312,7 @@ static jl_value_t *eval(jl_value_t *e, jl_value_t **locals, size_t nl, size_t ng
         jl_gc_wb_binding(b, dt);
         super = eval(args[2], locals, nl, ngensym);
         jl_set_datatype_super(dt, super);
+        jl_reinstantiate_inner_types(dt);
         b->value = temp;
         if (temp==NULL || !equiv_type(dt, (jl_datatype_t*)temp)) {
             jl_checked_assignment(b, (jl_value_t*)dt);
@@ -326,6 +344,7 @@ static jl_value_t *eval(jl_value_t *e, jl_value_t **locals, size_t nl, size_t ng
         jl_gc_wb_binding(b, dt);
         super = eval(args[3], locals, nl, ngensym);
         jl_set_datatype_super(dt, super);
+        jl_reinstantiate_inner_types(dt);
         b->value = temp;
         if (temp==NULL || !equiv_type(dt, (jl_datatype_t*)temp)) {
             jl_checked_assignment(b, (jl_value_t*)dt);
@@ -355,6 +374,8 @@ static jl_value_t *eval(jl_value_t *e, jl_value_t **locals, size_t nl, size_t ng
         jl_gc_wb_binding(b,dt);
 
         JL_TRY {
+            super = eval(args[3], locals, nl, ngensym);
+            jl_set_datatype_super(dt, super);
             // operations that can fail
             inside_typedef = 1;
             dt->types = (jl_svec_t*)eval(args[4], locals, nl, ngensym);
@@ -367,8 +388,7 @@ static jl_value_t *eval(jl_value_t *e, jl_value_t **locals, size_t nl, size_t ng
                                      "type definition",
                                      (jl_value_t*)jl_type_type, elt);
             }
-            super = eval(args[3], locals, nl, ngensym);
-            jl_set_datatype_super(dt, super);
+            jl_reinstantiate_inner_types(dt);
         }
         JL_CATCH {
             b->value = temp;
diff --git a/src/jltypes.c b/src/jltypes.c
index c2390c960d0cc..af772996729ac 100644
--- a/src/jltypes.c
+++ b/src/jltypes.c
@@ -2372,6 +2372,9 @@ void jl_reinstantiate_inner_types(jl_datatype_t *t)
     top.tt = t;
     top.prev = NULL;
     size_t n = jl_svec_len(t->parameters);
+    if (n == 0) return;
+    t->name->cache = jl_emptysvec;
+    t->name->linearcache = jl_emptysvec;
     jl_value_t **env = (jl_value_t**)alloca(n*2*sizeof(void*));
     for(int i=0; i < n; i++) {
         env[i*2] = jl_svecref(t->parameters,i);
diff --git a/src/julia_internal.h b/src/julia_internal.h
index 6318cf7cfac2d..919654a4dd931 100644
--- a/src/julia_internal.h
+++ b/src/julia_internal.h
@@ -210,9 +210,6 @@ jl_value_t *jl_first_argument_datatype(jl_value_t *argtypes);
 jl_value_t *jl_preresolve_globals(jl_value_t *expr, jl_lambda_info_t *lam);
 int jl_has_intrinsics(jl_lambda_info_t *li, jl_expr_t *e, jl_module_t *m);
 
-void jl_set_datatype_super(jl_datatype_t *tt, jl_value_t *super);
-void jl_add_constructors(jl_datatype_t *t);
-
 jl_value_t *jl_nth_slot_type(jl_tupletype_t *sig, size_t i);
 void jl_compute_field_offsets(jl_datatype_t *st);
 jl_array_t *jl_new_array_for_deserialization(jl_value_t *atype, uint32_t ndims, size_t *dims,
diff --git a/src/toplevel.c b/src/toplevel.c
index 24592a6d17766..5a4d977b5ecf8 100644
--- a/src/toplevel.c
+++ b/src/toplevel.c
@@ -582,30 +582,6 @@ JL_DLLEXPORT jl_value_t *jl_load_(jl_value_t *str)
     return jl_load(jl_string_data(str), jl_string_len(str));
 }
 
-// type definition ------------------------------------------------------------
-
-void jl_reinstantiate_inner_types(jl_datatype_t *t);
-
-void jl_set_datatype_super(jl_datatype_t *tt, jl_value_t *super)
-{
-    if (!jl_is_datatype(super) || !jl_is_abstracttype(super) ||
-        tt->name == ((jl_datatype_t*)super)->name ||
-        jl_subtype(super,(jl_value_t*)jl_vararg_type,0) ||
-        jl_is_tuple_type(super) ||
-        jl_subtype(super,(jl_value_t*)jl_type_type,0) ||
-        super == (jl_value_t*)jl_builtin_type) {
-        jl_errorf("invalid subtyping in definition of %s",
-                  jl_symbol_name(tt->name->name));
-    }
-    tt->super = (jl_datatype_t*)super;
-    jl_gc_wb(tt, tt->super);
-    if (jl_svec_len(tt->parameters) > 0) {
-        tt->name->cache = jl_emptysvec;
-        tt->name->linearcache = jl_emptysvec;
-        jl_reinstantiate_inner_types(tt);
-    }
-}
-
 // method definition ----------------------------------------------------------
 
 extern int jl_boot_file_loaded;
diff --git a/test/core.jl b/test/core.jl
index 283c74cb520b7..51acdb9aeb0f7 100644
--- a/test/core.jl
+++ b/test/core.jl
@@ -3696,3 +3696,18 @@ let
     c=1
     @test b() == 1
 end
+
+# issue #14825
+abstract abstest_14825
+
+type t1_14825{A <: abstest_14825, B}
+  x::A
+  y::B
+end
+
+type t2_14825{C, B} <: abstest_14825
+  x::C
+  y::t1_14825{t2_14825{C, B}, B}
+end
+
+@test t2_14825{Int,Int}.types[2] <: t1_14825