diff --git a/include/heimqueue.h b/include/heimqueue.h
index f54f7d7a2..5e922cfcb 100644
--- a/include/heimqueue.h
+++ b/include/heimqueue.h
@@ -100,16 +100,25 @@ struct {								\
  */
 #include "heimbase.h"
 
+#define	HEIM_SLIST_ATOMIC_HEAD(name, type)				\
+struct name {								\
+	heim_base_atomic(struct type *) slh_first; /* first element */	\
+}
+
+#define	HEIM_SLIST_ATOMIC_ENTRY(type)					\
+struct {								\
+	heim_base_atomic(struct type *) sle_next; /* next element */	\
+}
+
 #define HEIM_SLIST_ATOMIC_INSERT_HEAD(head, elm, field) do {		\
 	(elm)->field.sle_next =						\
 	    heim_base_exchange_pointer(&(head)->slh_first, (elm));	\
 } while (/*CONSTCOND*/0)
 
-#define HEIM_SLIST_ATOMIC_FOREACH(var, head, field)			        \
-	for ((void)heim_base_exchange_pointer(&(var), (head)->slh_first);	\
-	     (var) != NULL;						        \
-	     (void)heim_base_exchange_pointer(&(var), (var)->field.sle_next))
-
+#define HEIM_SLIST_ATOMIC_FOREACH(var, head, field)			\
+	for ((var) = heim_base_atomic_load(&(head)->slh_first);		\
+	     (var) != NULL;						\
+	     (var) = heim_base_atomic_load(&(var)->field.sle_next))
 /*
  * Tail queue definitions.
  */
diff --git a/lib/gssapi/mech/gss_utils.c b/lib/gssapi/mech/gss_utils.c
index e622d8ff8..e12b3bd2f 100644
--- a/lib/gssapi/mech/gss_utils.c
+++ b/lib/gssapi/mech/gss_utils.c
@@ -60,11 +60,11 @@ _gss_free_oid(OM_uint32 *minor_status, gss_OID oid)
 }
 
 struct _gss_interned_oid {
-    HEIM_SLIST_ENTRY(_gss_interned_oid) gio_link;
+    HEIM_SLIST_ATOMIC_ENTRY(_gss_interned_oid) gio_link;
     gss_OID_desc gio_oid;
 };
 
-static HEIM_SLIST_HEAD(_gss_interned_oid_list, _gss_interned_oid) interned_oids =
+static HEIM_SLIST_ATOMIC_HEAD(_gss_interned_oid_list, _gss_interned_oid) interned_oids =
 HEIM_SLIST_HEAD_INITIALIZER(interned_oids);
 
 extern gss_OID _gss_ot_internal[];