From d111a6bea7db6de71fabba0a5375945dc9530f36 Mon Sep 17 00:00:00 2001
From: Adam David <adam@FreeBSD.org>
Date: Sun, 25 Sep 1994 04:57:44 +0000
Subject: [PATCH] Dumped core when prompt == NULL

---
 gnu/lib/libreadline/readline.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gnu/lib/libreadline/readline.c b/gnu/lib/libreadline/readline.c
index ee624c1e7670..941243ed76f0 100644
--- a/gnu/lib/libreadline/readline.c
+++ b/gnu/lib/libreadline/readline.c
@@ -278,7 +278,8 @@ readline (prompt)
       return ((char *)NULL);
     }
 
-  rl_visible_prompt_length = rl_expand_prompt (rl_prompt);
+  if (rl_prompt != NULL)
+    rl_visible_prompt_length = rl_expand_prompt (rl_prompt);
 
   rl_initialize ();
   rl_prep_terminal (_rl_meta_flag);