Avoid unmap of memory allocated during GC init regardless of threshold

* alloc.c [USE_MUNMAP] (GC_finish_collection): Do not call
GC_unmap_old() at the first GC; add comment.

1 files changed, 2 insertions, 1 deletions

diff --git a/alloc.c b/alloc.c
index a72db17e..bb2071cf 100644
--- a/alloc.c
+++ b/alloc.c
@@ -1193,7 +1193,8 @@ STATIC void GC_finish_collection(void)
     GC_start_reclaim(FALSE);
 
 #   ifdef USE_MUNMAP
-      GC_unmap_old();
+      if (EXPECT(GC_gc_no != 1, TRUE)) /* do not unmap during GC init */
+        GC_unmap_old();
 
       GC_ASSERT(GC_heapsize >= GC_unmapped_bytes);
 #   endif