diff --git a/xpath.c b/xpath.c
index c4794ea8..30ba4871 100644
--- a/xpath.c
+++ b/xpath.c
@@ -1467,6 +1467,10 @@ xmlXPathDebugDumpStepOp(FILE *output, xmlXPathCompExprPtr comp,
     }
     fprintf(output, "\n");
 finish:
+    /* OP_VALUE has invalid ch1. */
+    if (op->op == XPATH_OP_VALUE)
+        return;
+
     if (op->ch1 >= 0)
 	xmlXPathDebugDumpStepOp(output, comp, &comp->steps[op->ch1], depth + 1);
     if (op->ch2 >= 0)