bug#30626: 26.0.91; Crash when traversing a `stream-of-directory-files'

[Michael Heerdegen <michael_heerdegen@web.de>]

Hello,

Traversing a `stream-of-directory-files' over a huge directory hierarchy
crashes my Emacs.

Here is a recipe: I have a file
"/home/micha/Treasure/today/stream-crash.el" with these contents:

#+begin_src emacs-lisp
;; -*- lexical-binding: t -*-

(require 'stream)

(seq-doseq (_file (stream-of-directory-files
                   "/home/micha" t nil t nil
                   (lambda (file) (and (file-readable-p file) (file-regular-p file)))))
  nil)
#+end_src

Then I

micha> emacs -Q -L /home/micha/software/elpa/packages/stream\
                -l /home/micha/Treasure/today/stream-crash.el

and I get a segfault after ~ 1 minute.

This kind of crash only seems to occur when the traversed directory is
sufficiently large.


Thanks in advance,

Michael.


In GNU Emacs 26.0.91 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.22.28)
 of 2018-02-26 built on drachen
Repository revision: ea8f9fd7be138708a52aad418d09d5d4ca6b2a7e
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
System Description:	Debian GNU/Linux testing (buster)