diff --git a/include/runtime/header.h b/include/runtime/header.h
index d82cae004..3846e4ef3 100644
--- a/include/runtime/header.h
+++ b/include/runtime/header.h
@@ -91,7 +91,10 @@ struct kore_alloc_heap {
   template <typename... Tags>
   static void *allocate(size_t size, Tags...) {
     if (during_gc()) {
-      return ::operator new(size);
+      auto *result = (string *)::operator new(size + sizeof(blockheader));
+      init_with_len(result, size);
+      result->h.hdr |= NOT_YOUNG_OBJECT_BIT;
+      return result->data;
     }
     bool enabled = gc_enabled;
     gc_enabled = false;
@@ -103,7 +106,7 @@ struct kore_alloc_heap {
 
   static void deallocate(size_t size, void *data) {
     if (during_gc()) {
-      ::operator delete(data);
+      ::operator delete((char *)data - sizeof(blockheader));
     }
   }
 };
diff --git a/runtime/collect/collect.cpp b/runtime/collect/collect.cpp
index c439fdd0e..fd3e59eeb 100644
--- a/runtime/collect/collect.cpp
+++ b/runtime/collect/collect.cpp
@@ -274,9 +274,11 @@ static bool should_collect_old_gen() {
 }
 
 void init_static_objects(void) {
+  is_gc = true;
   map m = map();
   list l = list();
   set s = set();
+  is_gc = false;
   set_kore_memory_functions_for_gmp();
 }
 
diff --git a/runtime/collect/migrate_static_roots.cpp b/runtime/collect/migrate_static_roots.cpp
index 3474e83ee..4a47f8e0d 100644
--- a/runtime/collect/migrate_static_roots.cpp
+++ b/runtime/collect/migrate_static_roots.cpp
@@ -10,14 +10,6 @@ extern thread_local bool kllvm_rand_state_initialized;
 extern "C" {
 
 void migrate_static_roots() {
-  auto &l1 = list_impl::empty_root();
-  migrate_collection_node((void **)&l1);
-  auto &l2 = list_impl::empty_tail();
-  migrate_collection_node((void **)&l2);
-  auto &s = set_impl::empty();
-  migrate_collection_node((void **)&s);
-  auto &m = map_impl::empty();
-  migrate_collection_node((void **)&m);
   if (kllvm_rand_state_initialized) {
     auto &rand = kllvm_rand_state->_mp_seed->_mp_d;
     string *limbs = STRUCT_BASE(string, data, rand);