diff --git a/src/dump.c b/src/dump.c
index ae3e4991b86ef..e19876d0ef285 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -196,7 +196,7 @@ static void jl_serialize_datatype(jl_serializer_state *s, jl_datatype_t *dt) JL_
     if (!internal && jl_unwrap_unionall(dt->name->wrapper) == (jl_value_t*)dt) {
         tag = 6; // external primary type
     }
-    else if (!dt->isconcretetype) {
+    else if (jl_is_tuple_type(dt) ? !dt->isconcretetype : dt->hasfreetypevars) {
         tag = 0; // normal struct
     }
     else if (internal) {
@@ -212,8 +212,8 @@ static void jl_serialize_datatype(jl_serializer_state *s, jl_datatype_t *dt) JL_
         tag = 11; // external, but definitely new (still needs caching, but not full unique-ing)
     }
     else {
-        // this'll need unique-ing later
-        // flag this in the backref table as special
+        // this is eligible for (and possibly requires) unique-ing later,
+        // so flag this in the backref table as special
         uintptr_t *bp = (uintptr_t*)ptrhash_bp(&backref_table, dt);
         assert(*bp != (uintptr_t)HT_NOTFOUND);
         *bp |= 1;
diff --git a/test/precompile.jl b/test/precompile.jl
index a6aa60009ba6e..f69e7a4766f2c 100644
--- a/test/precompile.jl
+++ b/test/precompile.jl
@@ -95,6 +95,7 @@ precompile_test_harness(false) do dir
               const t17809s = Any[
                     Tuple{
                         Type{Ptr{MyType{i}}},
+                        Ptr{Type{MyType{i}}},
                         Array{Ptr{MyType{MyType{:sym}()}}(0), 0},
                         Val{Complex{Int}(1, 2)},
                         Val{3},
@@ -340,6 +341,7 @@ precompile_test_harness(false) do dir
         @test all(i -> Foo.t17809s[i + 1] ===
             Tuple{
                 Type{Ptr{Foo.MyType{i}}},
+                Ptr{Type{Foo.MyType{i}}},
                 Array{Ptr{Foo.MyType{Foo.MyType{:sym}()}}(0), 0},
                 Val{Complex{Int}(1, 2)},
                 Val{3},