Fixes: debbugs:11917

Fix crash when creating indirect buffer
* buffer.c (buffer_lisp_local_variables): Add argument CLONE.
Don't handle unbound variables specially if non-zero.
(Fbuffer_local_variables): Pass zero.
(clone_per_buffer_values): Pass non-zero.

diff --git a/src/ChangeLog b/src/ChangeLog
index ea44367e2bd7a9a5c4ed5cc251621ca0e2ac18f1..7274fc4e4d8a82212b6d801840cd797745aeeb21 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,11 @@
+2012-07-12  Andreas Schwab  <schwab@linux-m68k.org>
+
+       Fix crash when creating indirect buffer (Bug#11917)
+       * buffer.c (buffer_lisp_local_variables): Add argument CLONE.
+       Don't handle unbound variables specially if non-zero.
+       (Fbuffer_local_variables): Pass zero.
+       (clone_per_buffer_values): Pass non-zero.
+
 2012-06-28  Andreas Schwab  <schwab@linux-m68k.org>
 
        * gnutls.c (emacs_gnutls_handshake): Revert last change.  Add QUIT

diff --git a/src/buffer.c b/src/buffer.c
index ac14ec9c37cb6363df088b2dab2bc913ee5b79df..88ef34070ea659628e0a8ec2fd1aadb3ef0b1be7 100644 (file)
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -156,7 +156,7 @@ static void alloc_buffer_text (struct buffer *, ptrdiff_t);
 static void free_buffer_text (struct buffer *b);
 static struct Lisp_Overlay * copy_overlays (struct buffer *, struct Lisp_Overlay *);
 static void modify_overlay (struct buffer *, EMACS_INT, EMACS_INT);
-static Lisp_Object buffer_lisp_local_variables (struct buffer *);
+static Lisp_Object buffer_lisp_local_variables (struct buffer *, int);
 
 /* For debugging; temporary.  See set_buffer_internal.  */
 /* Lisp_Object Qlisp_mode, Vcheck_symbol; */
@@ -505,7 +505,7 @@ clone_per_buffer_values (struct buffer *from, struct buffer *to)
 
   /* Get (a copy of) the alist of Lisp-level local variables of FROM
      and install that in TO.  */
-  BVAR (to, local_var_alist) = buffer_lisp_local_variables (from);
+  BVAR (to, local_var_alist) = buffer_lisp_local_variables (from, 1);
 }
 
 
@@ -1003,10 +1003,12 @@ is the default binding of the variable. */)
 
 /* Return an alist of the Lisp-level buffer-local bindings of
    buffer BUF.  That is, don't include the variables maintained
-   in special slots in the buffer object.  */
+   in special slots in the buffer object.
+   If CLONE is zero elements of the form (VAR . unbound) are replaced
+   by VAR.  */
 
 static Lisp_Object
-buffer_lisp_local_variables (struct buffer *buf)
+buffer_lisp_local_variables (struct buffer *buf, int clone)
 {
   Lisp_Object result = Qnil;
   register Lisp_Object tail;
@@ -1026,7 +1028,7 @@ buffer_lisp_local_variables (struct buffer *buf)
       if (buf != current_buffer)
        val = XCDR (elt);
 
-      result = Fcons (EQ (val, Qunbound)
+      result = Fcons (!clone && EQ (val, Qunbound)
                      ? XCAR (elt)
                      : Fcons (XCAR (elt), val),
                      result);
@@ -1055,7 +1057,7 @@ No argument or nil as argument means use current buffer as BUFFER.  */)
       buf = XBUFFER (buffer);
     }
 
-  result = buffer_lisp_local_variables (buf);
+  result = buffer_lisp_local_variables (buf, 0);
 
   /* Add on all the variables stored in special slots.  */
   {