* fixed bug in handling tcbuckets.

Summary of the bug:  
    if ik_alloc is called during gc, and if it causes a heap
    overflow, then the pages are deallocated before returning to
    scheme.

bin/ikarus-collect.c

@@ -320,6 +320,9 @@ ik_collect(int mem_req, ikpcb* pcb){
       gc.collect_gen, pcb->collection_id-1);
 #endif
 
+  /* cache heap-pages to delete later */
+  ikpages* old_heap_pages = pcb->heap_pages;
+  pcb->heap_pages = 0;
 
   /* the roots are:
    *  0. dirty pages not collected in this run
@@ -327,6 +330,7 @@ ik_collect(int mem_req, ikpcb* pcb){
    *  2. the next continuation
    *  3. the symbol-table
    */
+
   scan_dirty_pages(&gc);
   collect_stack(&gc, pcb->frame_pointer, pcb->frame_base - wordsize);
   pcb->next_k = add_object(&gc, pcb->next_k, "next_k"); 
@@ -400,15 +404,15 @@ ik_collect(int mem_req, ikpcb* pcb){
   }
  
   /* delete all old heap pages */
-  if(pcb->heap_pages){
-    ikpages* p = pcb->heap_pages;
+  if(old_heap_pages){
+    ikpages* p = old_heap_pages;
     do{
       ikpages* next = p->next;
       ik_munmap_from_segment(p->base, p->size, pcb);
       ik_free(p, sizeof(ikpages));
       p=next;
     } while(p);
-    pcb->heap_pages = 0;
+    old_heap_pages = 0;
   }
 
   int free_space = 
@@ -1621,6 +1625,7 @@ fix_new_pages(gc_t* gc){
   }
 } 
 
+
 static void
 add_one_tconc(ikpcb* pcb, ikp tcbucket){
   ikp tc = ref(tcbucket, off_tcbucket_tconc);

src/libcompile.ss

@@ -5109,7 +5109,8 @@
               (newline)
               (for-each (lambda (x) (printf "    ~s\n" x)) ls))
             ls*)))
-      (let ([code* (list*->code* 
+      (let ([code* 
+             (list*->code* 
                (lambda (x)
                  (if (closure? x)
                      (if (null? (closure-free* x))