tags 39884 + patch
quit

"Rainer Gemulla" <rgemulla@gmx.de> writes:

> During step 9, this statement is executed, but afterwards, the tag
> variable is not set to the list mentioned in the statement
> (seriously!). In my case, it had value 'Content-Type:
> multipart/alternative; boundary="====-=-="' right afterwards

Yes, it's due destructive modification of a quoted literal value.  To
catch it, I modified mml.el like this:

--- i/lisp/gnus/mml.el
+++ w/lisp/gnus/mml.el
@@ -216,6 +216,8 @@ mml-parse
     (with-syntax-table mml-syntax-table
       (mml-parse-1))))
 
+(defconst mml-text/plain-tag-literal-constant '(type . "text/plain"))
+
 (defun mml-parse-1 ()
   "Parse the current buffer as an MML document."
   (let (struct tag point contents charsets warn use-ascii no-markup-p raw)
@@ -281,7 +283,7 @@ mml-parse-1
 	    (setq tag (mml-read-tag)
 		  no-markup-p nil
 		  warn nil)
-	  (setq tag (list 'part '(type . "text/plain"))
+	  (setq tag (list 'part mml-text/plain-tag-literal-constant)
 		no-markup-p t
 		warn t))
 	(setq raw (cdr (assq 'raw tag))

And added a debug check around setcdr as in the attached
bug-39884-bad-mml-parsing.el file.