diff --git a/src/mzscheme/gc2/fnls.c b/src/mzscheme/gc2/fnls.c
index e0b95bd8c8..18f0352eaa 100644
--- a/src/mzscheme/gc2/fnls.c
+++ b/src/mzscheme/gc2/fnls.c
@@ -81,16 +81,16 @@ void GC_set_finalizer(void *p, int tagged, int level, void (*f)(void *p, void *d
     return;
 
   /* Allcation might trigger GC, so we use park: */
-  park[0] = p;
-  park[1] = data;
+  GC->park[0] = p;
+  GC->park[1] = data;
 
   fnl = (Fnl *)GC_malloc_atomic(sizeof(Fnl));
   memset(fnl, 0, sizeof(Fnl));
 
-  p = park[0];
-  park[0] = NULL;
-  data = park[1];
-  park[1] = NULL;
+  p = GC->park[0];
+  data = GC->park[1];
+  GC->park[0] = NULL;
+  GC->park[1] = NULL;
 
   fnl->next = finalizers;
   fnl->prev = NULL;
diff --git a/src/mzscheme/gc2/newgc.c b/src/mzscheme/gc2/newgc.c
index 844548c6bc..4f2f440543 100644
--- a/src/mzscheme/gc2/newgc.c
+++ b/src/mzscheme/gc2/newgc.c
@@ -110,9 +110,6 @@ void (*GC_fixup_xtagged)(void *obj);
 
 #include "my_qsort.c"
 
-static void *park[2];
-static void *park_save[2];
-
 /*****************************************************************************/
 /* OS-Level Memory Management Routines                                       */
 /*****************************************************************************/
@@ -1108,8 +1105,8 @@ void GC_finalization_weak_ptr(void **p, int offset)
 {
   struct weak_finalizer *wfnl;
 
-  park[0] = p; wfnl = GC_malloc_atomic(sizeof(struct weak_finalizer));
-  p = park[0]; park[0] = NULL;
+  GC->park[0] = p; wfnl = GC_malloc_atomic(sizeof(struct weak_finalizer));
+  p = GC->park[0]; GC->park[0] = NULL;
   wfnl->p = p; wfnl->offset = offset * sizeof(void*); wfnl->saved = NULL;
   wfnl->next = weak_finalizers; weak_finalizers = wfnl;
 }
@@ -1471,8 +1468,8 @@ void GC_init_type_tags(int count, int pair, int mutable_pair, int weakbox, int e
     GC_register_traversers(GC->ephemeron_tag, size_ephemeron, mark_ephemeron, fixup_ephemeron, 0, 0);
     GC_register_traversers(GC->weak_array_tag, size_weak_array, mark_weak_array, fixup_weak_array, 0, 0);
     initialize_signal_handler();
-    GC_add_roots(&park, (char *)&park + sizeof(park) + 1);
-    GC_add_roots(&park_save, (char *)&park_save + sizeof(park_save) + 1);
+    GC_add_roots(&GC->park, (char *)&GC->park + sizeof(GC->park) + 1);
+    GC_add_roots(&GC->park_save, (char *)&GC->park_save + sizeof(GC->park_save) + 1);
 
     initialize_protect_page_ranges(malloc_dirty_pages(APAGE_SIZE, APAGE_SIZE), APAGE_SIZE);
   }
@@ -2560,10 +2557,10 @@ static void garbage_collect(int force_full)
     running_finalizers = 1;
 
     /* Finalization might allocate, which might need park: */
-    park_save[0] = park[0];
-    park_save[1] = park[1];
-    park[0] = NULL;
-    park[1] = NULL;
+    GC->park_save[0] = GC->park[0];
+    GC->park_save[1] = GC->park[1];
+    GC->park[0] = NULL;
+    GC->park[1] = NULL;
 
     while(run_queue) {
       struct finalizer *f;
@@ -2581,10 +2578,10 @@ static void garbage_collect(int force_full)
     run_account_hooks();
     running_finalizers = 0;
 
-    park[0] = park_save[0];
-    park[1] = park_save[1];
-    park_save[0] = NULL;
-    park_save[1] = NULL;
+    GC->park[0] = GC->park_save[0];
+    GC->park[1] = GC->park_save[1];
+    GC->park_save[0] = NULL;
+    GC->park_save[1] = NULL;
   }
 
   DUMP_HEAP(); CLOSE_DEBUG_FILE();
diff --git a/src/mzscheme/gc2/newgc_internal.h b/src/mzscheme/gc2/newgc_internal.h
index f664506425..f4167136b4 100644
--- a/src/mzscheme/gc2/newgc_internal.h
+++ b/src/mzscheme/gc2/newgc_internal.h
@@ -82,6 +82,19 @@ typedef struct NewGC {
   unsigned long in_unsafe_allocation_mode :1;
   void (*unsafe_allocation_abort)();
 
+  void *park[2];
+  void *park_save[2];
+
+  int generations_available;
+  unsigned char full_needed_for_finalization :1;
+  unsigned char no_further_modifications:1;
+
+  /* These collect information about memory usage, for use in GC_dump. */
+  unsigned long peak_memory_use;
+  unsigned long num_minor_collects;
+  unsigned long num_major_collects;
+
+
   unsigned short weak_array_tag;
   unsigned short weak_box_tag;
   unsigned short ephemeron_tag;
@@ -114,4 +127,5 @@ void NewGC_initialize(NewGC *newgc) {
   newgc->weak_boxes = NULL;
   newgc->ephemerons = NULL;
   newgc->num_last_seen_ephemerons = 0;
+  newgc->generations_available = 1;
 }
diff --git a/src/mzscheme/gc2/newgc_parts/blame_the_child.c b/src/mzscheme/gc2/newgc_parts/blame_the_child.c
index 6132a19045..3d61d97bd4 100644
--- a/src/mzscheme/gc2/newgc_parts/blame_the_child.c
+++ b/src/mzscheme/gc2/newgc_parts/blame_the_child.c
@@ -146,11 +146,11 @@ inline static unsigned long custodian_usage(void *custodian)
   int i;
   
   if(!really_doing_accounting) {
-    park[0] = custodian;
+    GC->park[0] = custodian;
     really_doing_accounting = 1;
     garbage_collect(1);
-    custodian = park[0]; 
-    park[0] = NULL;
+    custodian = GC->park[0]; 
+    GC->park[0] = NULL;
   }
   for(i = 1; i < owner_table_top; i++)
     if(owner_table[i] && custodian_member_owner_set(custodian, i)) 
@@ -359,11 +359,11 @@ inline static void add_account_hook(int type,void *c1,void *c2,unsigned long b)
   struct account_hook *work;
 
   if(!really_doing_accounting) {
-    park[0] = c1; park[1] = c2;
+    GC->park[0] = c1; GC->park[1] = c2;
     really_doing_accounting = 1;
     garbage_collect(1);
-    c1 = park[0]; c2 = park[1];
-    park[0] = park[1] = NULL;
+    c1 = GC->park[0]; c2 = GC->park[1];
+    GC->park[0] = GC->park[1] = NULL;
   }
 
   if (type == MZACCT_LIMIT)
diff --git a/src/mzscheme/gc2/weak.c b/src/mzscheme/gc2/weak.c
index 1397ae8963..8c2299d8aa 100644
--- a/src/mzscheme/gc2/weak.c
+++ b/src/mzscheme/gc2/weak.c
@@ -88,14 +88,14 @@ void *GC_malloc_weak_array(size_t size_in_bytes, void *replace_val)
   GC_Weak_Array *w;
 
   /* Allcation might trigger GC, so we use park: */
-  park[0] = replace_val;
+  GC->park[0] = replace_val;
 
   w = (GC_Weak_Array *)GC_malloc_one_tagged(size_in_bytes 
 					    + sizeof(GC_Weak_Array) 
 					    - sizeof(void *));
 
-  replace_val = park[0];
-  park[0] = NULL;
+  replace_val = GC->park[0];
+  GC->park[0] = NULL;
 
   w->type = GC->weak_array_tag;
   w->replace_val = replace_val;
@@ -168,15 +168,15 @@ void *GC_malloc_weak_box(void *p, void **secondary, int soffset)
   GC_Weak_Box *w;
 
   /* Allcation might trigger GC, so we use park: */
-  park[0] = p;
-  park[1] = secondary;
+  GC->park[0] = p;
+  GC->park[1] = secondary;
 
   w = (GC_Weak_Box *)GC_malloc_one_tagged(sizeof(GC_Weak_Box));
 
-  p = park[0];
-  park[0] = NULL;
-  secondary = (void **)park[1];
-  park[1] = NULL;
+  p = GC->park[0];
+  secondary = (void **)GC->park[1];
+  GC->park[0] = NULL;
+  GC->park[1] = NULL;
   
   w->type = GC->weak_box_tag;
   w->val = p;
@@ -262,15 +262,15 @@ void *GC_malloc_ephemeron(void *k, void *v)
   GC_Ephemeron *eph;
 
   /* Allcation might trigger GC, so we use park: */
-  park[0] = k;
-  park[1] = v;
+  GC->park[0] = k;
+  GC->park[1] = v;
 
   eph = (GC_Ephemeron *)GC_malloc_one_tagged(sizeof(GC_Ephemeron));
 
-  k = park[0];
-  park[0] = NULL;
-  v = park[1];
-  park[1] = NULL;
+  k = GC->park[0];
+  v = GC->park[1];
+  GC->park[0] = NULL;
+  GC->park[1] = NULL;
   
   eph->type = GC->ephemeron_tag;
   eph->key = k;