diff --git a/lib/clixon/clixon_xpath.h b/lib/clixon/clixon_xpath.h
index 3ccf4b9a4..53a655b6f 100644
--- a/lib/clixon/clixon_xpath.h
+++ b/lib/clixon/clixon_xpath.h
@@ -118,10 +118,10 @@ struct xpath_tree{
     struct xpath_tree *xs_c0;     /* child 0 */
     struct xpath_tree *xs_c1;     /* child 1 */
     int                xs_match;  /* meta: match this node */
-#ifdef XPATH_CURRENT_OPTIMIZE
+    /* Unconditional (not only XPATH_CURRENT_OPTIMIZE): struct layout must not depend on
+     * compile options, see https://github.com/clicon/clixon/issues/698 */
     void              *xs_cached_result;   /* xp_ctx *: cached evaluation result */
     void              *xs_cached_initial;  /* cxobj *: xc_initial for which cache is valid */
-#endif
 };
 typedef struct xpath_tree xpath_tree;
 
diff --git a/lib/clixon/clixon_xpath_ctx.h b/lib/clixon/clixon_xpath_ctx.h
index 4f4ba58fb..002734d9f 100644
--- a/lib/clixon/clixon_xpath_ctx.h
+++ b/lib/clixon/clixon_xpath_ctx.h
@@ -88,9 +88,9 @@ struct xp_ctx{
     cxobj          *xc_initial; /* RFC 7960 10.1.1 extension: for current() */
     int             xc_descendant;  /* // */
     /* NYI: a set of variable bindings, set of namespace declarations */
-#ifdef XPATH_CURRENT_OPTIMIZE
+    /* Unconditional (not only XPATH_CURRENT_OPTIMIZE): struct layout must not depend on
+     * compile options, see https://github.com/clicon/clixon/issues/698 */
     int             xc_invariant;   /* result depends only on xc_initial (current()) */
-#endif
 };
 typedef struct xp_ctx xp_ctx;
 
diff --git a/lib/src/clixon_xpath_ctx.c b/lib/src/clixon_xpath_ctx.c
index f1022e67b..d8e7f256c 100644
--- a/lib/src/clixon_xpath_ctx.c
+++ b/lib/src/clixon_xpath_ctx.c
@@ -36,6 +36,10 @@
  * Clixon XML XPath 1.0 according to https://www.w3.org/TR/xpath-10
  * This file defines XPath contexts used in traversing the XPath parse tree.
  */
+#ifdef HAVE_CONFIG_H
+#include "clixon_config.h" /* generated by config & autoconf */
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>