Relax assertion of hb_n_marks in reclaim_block if more than two markers

(fix of commit c9be25027)

Issue #412 (bdwgc).

* reclaim.c [PARALLEL_MARK] (GC_reclaim_block): Use
min(3,GC_markers_m1+1) (instead of hard-coded 2) multiplier in the
assertion about hb_n_marks maximum value; update the relevant comment.

1 files changed, 3 insertions, 2 deletions

diff --git a/reclaim.c b/reclaim.c
index cca47310..d3b54a68 100644
--- a/reclaim.c
+++ b/reclaim.c
@@ -435,10 +435,11 @@ STATIC void GC_reclaim_block(struct hblk *hbp, word report_if_found)
           /* Count can be low or one too high because we sometimes      */
           /* have to ignore decrements.  Objects can also potentially   */
           /* be repeatedly marked by each marker.                       */
-          /* Here we assume two markers, but this is extremely          */
+          /* Here we assume 3 markers at most, but this is extremely    */
           /* unlikely to fail spuriously with more.  And if it does, it */
           /* should be looked at.                                       */
-          GC_ASSERT(sz != 0 && hhdr->hb_n_marks <= 2 * (HBLKSIZE/sz + 1) + 16);
+          GC_ASSERT(sz != 0 && (GC_markers_m1 > 1 ? 3 : GC_markers_m1 + 1)
+                                * (HBLKSIZE/sz + 1) + 16 >= hhdr->hb_n_marks);
 #       else
           GC_ASSERT(sz * hhdr -> hb_n_marks <= HBLKSIZE);
 #       endif