From e35e3e3b33d5bd4e1163b81e2e581899a5713cda Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Wed, 1 Sep 2021 10:57:27 +0200
Subject: [PATCH] prevent a crash, e.g. when incompatible 'option interp' is
 set and 'stop' is called.

---
 src/frontend/breakp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/frontend/breakp.c b/src/frontend/breakp.c
index 86acbfd4b..a7b1bc398 100644
--- a/src/frontend/breakp.c
+++ b/src/frontend/breakp.c
@@ -475,10 +475,14 @@ satisfied(struct dbcomm *d, struct plot *plot)
             fprintf(cp_err, "Error: %s: no such node\n", d->db_nodename1);
             return (FALSE);
         }
+        if (v1->v_length == 0)
+            return (FALSE);
+
         if (isreal(v1))
             d1 = v1->v_realdata[v1->v_length - 1];
         else
             d1 = realpart((v1->v_compdata[v1->v_length - 1]));
+
     } else {
         d1 = d->db_value1;
     }