Improve GCBits invariant

diff --git a/rt/gc/cdgc/bits.d b/rt/gc/cdgc/bits.d
index 3dd8f34f9d50966e578bc21a0e29bd6ad4c43d8c..17b71f31d5849d5eb6bb9a46c0a270c97ca018d7 100644 (file)
--- a/rt/gc/cdgc/bits.d
+++ b/rt/gc/cdgc/bits.d
@@ -83,9 +83,8 @@ struct GCBits
     invariant
     {
         if (data)
-        {
-            assert(nwords * data[0].sizeof * 8 >= nbits);
-        }
+            assert (nwords ==
+                    ((nbits + (BITS_PER_WORD - 1)) >> BITS_SHIFT));
     }
 
     void alloc(size_t nbits, os.Vis vis = os.Vis.PRIV)