From: Eli Zaretskii <eliz@gnu.org>
Date: Tue, 28 Aug 2018 07:20:46 +0000 (+0300)
Subject: Avoid crashes in malformed defvar
X-Git-Tag: emacs-26.1.90~186
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=63e59c8ca51ced6c4d5951281cb21288da32ced3;p=emacs.git

Avoid crashes in malformed defvar

* src/eval.c (Fdefvar): Don't call XSYMBOL on something that
might not be a symbol.  This avoids crashes due to malformed
'defvar' forms.  (Bug#32552)
---

diff --git a/src/eval.c b/src/eval.c
index 40cba3bb1ce..f9563a3f80c 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -773,7 +773,7 @@ usage: (defvar SYMBOL &optional INITVALUE DOCSTRING)  */)
       LOADHIST_ATTACH (sym);
     }
   else if (!NILP (Vinternal_interpreter_environment)
-	   && !XSYMBOL (sym)->u.s.declared_special)
+	   && (SYMBOLP (sym) && !XSYMBOL (sym)->u.s.declared_special))
     /* A simple (defvar foo) with lexical scoping does "nothing" except
        declare that var to be dynamically scoped *locally* (i.e. within
        the current file or let-block).  */