diff --git a/src/frontend/numparam/xpressn.c b/src/frontend/numparam/xpressn.c
index b88179775..0dc2bc7d3 100644
--- a/src/frontend/numparam/xpressn.c
+++ b/src/frontend/numparam/xpressn.c
@@ -1379,9 +1379,9 @@ getexpress(const char * const s, SPICE_DSTRINGPTR tstr_p, const char **pi)
             p++;
 
             if (p >= ls_ptr)
-                c = ';';
-            else
-                c = *p;
+                break;
+
+            c = *p;
 
             if (c == '(') {
                 /* sub-formula */