diff --git a/gc.c b/gc.c
index d5062a56..7716ea8c 100644
--- a/gc.c
+++ b/gc.c
@@ -262,6 +262,19 @@ size_t gc_sweep(gc_heap *h, size_t *sum_freed_ptr)
   return max_freed;
 }
 
+void gc_thr_grow_move_buffer(gc_thread_data *d){
+  if (!d) return;
+
+  if (d->moveBufLen == 0) { // Special case
+    d->moveBufLen = 128;
+    d->moveBuf = NULL;
+  } else {
+    d->moveBufLen *= 2;
+  }
+
+  d->moveBuf = realloc(d->moveBuf, d->moveBufLen);
+}
+
 // void gc_init()
 // {
 // }
diff --git a/include/cyclone/runtime-main.h b/include/cyclone/runtime-main.h
index a07e1535..012ece81 100644
--- a/include/cyclone/runtime-main.h
+++ b/include/cyclone/runtime-main.h
@@ -13,7 +13,6 @@
 
 long global_stack_size = 0;
 long global_heap_size = 0;
-gc_heap *Cyc_heap;
 
 static void c_entry_pt(int,closure,closure);
 static void Cyc_main(long stack_size,long heap_size,char *stack_base);
@@ -59,6 +58,10 @@ static void Cyc_main (stack_size,heap_size,stack_base)
 #endif
 
   Cyc_heap = gc_heap_create(heap_size, 0);
+  Cyc_thread = (gc_thread_data *)malloc(sizeof(gc_thread_data));
+  Cyc_thread->moveBufLen = 0;
+  gc_thr_grow_move_buffer(Cyc_thread); // Initialize the buffer
+  
 
   // JAE TODO: clean up below (and all of this old code, really)
   bottom = calloc(1,heap_size);
diff --git a/include/cyclone/types.h b/include/cyclone/types.h
index 92ff5ae7..29352735 100644
--- a/include/cyclone/types.h
+++ b/include/cyclone/types.h
@@ -20,6 +20,13 @@
 /* Define general object type. */
 typedef void *object;
 
+/* Thread data structures */
+typedef struct gc_thread_data_t gc_thread_data;
+struct gc_thread_data_t {
+  char *moveBuf; /* list of objects moved to heap during GC */
+  int moveBufLen;
+};
+
 /* GC data structures */
 
 typedef struct gc_free_list_t gc_free_list;
@@ -69,6 +76,7 @@ size_t gc_heap_total_size(gc_heap *h);
 void gc_mark(gc_heap *h, object obj);
 size_t gc_sweep(gc_heap *h, size_t *sum_freed_ptr);
 void gc_collect(gc_heap *h, size_t *sum_freed);
+void gc_thr_grow_move_buffer(gc_thread_data *d);
 
 /* GC debugging flags */
 //#define DEBUG_GC 0
diff --git a/runtime.c b/runtime.c
index 65afe17d..88ed51a0 100644
--- a/runtime.c
+++ b/runtime.c
@@ -9,6 +9,9 @@
 #include "cyclone/types.h"
 #include "cyclone/runtime.h"
 
+gc_heap *Cyc_heap;
+gc_thread_data *Cyc_thread;
+
 /* Error checking section - type mismatch, num args, etc */
 /* Type names to use for error messages */
 const char *tag_names[21] = { \
@@ -2405,7 +2408,7 @@ char *gc_move(char *obj) {
   } \
 }
 
-void GC(cont,ans,num_ans) closure cont; object *args; int num_args;
+void GC(cont, args, num_args) closure cont; object *args; int num_args;
 { 
   char tmp;
   object temp;