diff --git a/src/gc-stock.c b/src/gc-stock.c
index 845ff43909f0d..c53da51b58ecf 100644
--- a/src/gc-stock.c
+++ b/src/gc-stock.c
@@ -636,7 +636,7 @@ void jl_gc_reset_alloc_count(void) JL_NOTSAFEPOINT
 static void jl_gc_free_memory(jl_genericmemory_t *m, int isaligned) JL_NOTSAFEPOINT
 {
     assert(jl_is_genericmemory(m));
-    assert(jl_genericmemory_how(m) == 1 || jl_genericmemory_how(m) == 2);
+    assert(jl_genericmemory_how(m) == 1);
     char *d = (char*)m->ptr;
     size_t freed_bytes = memory_block_usable_size(d, isaligned);
     assert(freed_bytes != 0);
diff --git a/src/genericmemory.c b/src/genericmemory.c
index ae45237433fcc..dc1c687d1d382 100644
--- a/src/genericmemory.c
+++ b/src/genericmemory.c
@@ -199,7 +199,6 @@ JL_DLLEXPORT jl_value_t *jl_genericmemory_to_string(jl_genericmemory_t *m, size_
     size_t mlength = m->length;
     if (how != 0) {
         jl_value_t *o = jl_genericmemory_data_owner_field(m);
-        jl_genericmemory_data_owner_field(m) = NULL;
         if (how == 3 && // implies jl_is_string(o)
              ((mlength + sizeof(void*) + 1 <= GC_MAX_SZCLASS) == (len + sizeof(void*) + 1 <= GC_MAX_SZCLASS))) {
             if (jl_string_data(o)[len] != '\0')