Fix result computation in n_set_marks

* reclaim.c [!USE_MARK_BYTES] (GC_n_set_marks): Do not decrement the
result variable on return; add comment.

1 files changed, 1 insertions, 1 deletions

diff --git a/reclaim.c b/reclaim.c
index 90bf29a7..d50369e4 100644
--- a/reclaim.c
+++ b/reclaim.c
@@ -538,7 +538,7 @@ unsigned GC_n_set_marks(hdr *hhdr)
 #   else
       result += set_bits(hhdr -> hb_marks[n_mark_words - 1]);
 #   endif
-    return(result - 1);
+    return result; /* the number of set bits excluding the one past the end */
 }
 
 #endif /* !USE_MARK_BYTES  */