diff --git a/proto/ospf/lsalib.c b/proto/ospf/lsalib.c
index d6317125..f4bbe255 100644
--- a/proto/ospf/lsalib.c
+++ b/proto/ospf/lsalib.c
@@ -357,7 +357,7 @@ lsa_comp(struct ospf_lsa_header *l1, struct ospf_lsa_header *l2)
   if(sn1>sn2) return CMP_NEWER;
   if(sn1<sn2) return CMP_OLDER;
 
-  if(l1->checksum=!l2->checksum)
+  if(l1->checksum!=l2->checksum)
     return l1->checksum<l2->checksum ? CMP_OLDER : CMP_NEWER;
 
   if((l1->age==LSA_MAXAGE)&&(l2->age!=LSA_MAXAGE)) return CMP_NEWER;