bug#23739: Unexpected behavior of 'add-to-load-path'.

[Mathieu Lirzin <mthl@gnu.org>]

<tomas@tuxteam.de> writes:

> On Fri, Jun 10, 2016 at 02:17:23PM +0200, Mathieu Lirzin wrote:
>> Hello,
>> 
>> I have noticed something that doesn't feel right when using
>> ‘add-to-load-path’.
>> 
>> $ cat test.scm
>> --8<---------------cut here---------------start------------->8---
>> (define old %load-path)
>> (add-to-load-path "foo")
>> (pk %load-path)
>> (pk old)
>> --8<---------------cut here---------------end--------------->8---
>> 
>> first run:
>> 
>> $ guile test.scm
>> --8<---------------cut here---------------start------------->8---
>> ;;; [Compilation]
>> ;;; (("foo" "foo" "/usr/share/guile/2.0" "/usr/share/guile/site/2.0" "/usr/share/guile/site" "/usr/share/guile"))
>> 
>> ;;; (("foo" "/usr/share/guile/2.0" "/usr/share/guile/site/2.0" "/usr/share/guile/site" "/usr/share/guile"))
>> --8<---------------cut here---------------end--------------->8---
>> 
>> next runs:
>> 
>> $ guile test.scm
>> --8<---------------cut here---------------start------------->8---
>> ;;; (("foo" "/usr/share/guile/2.0" "/usr/share/guile/site/2.0" "/usr/share/guile/site" "/usr/share/guile"))
>> 
>> ;;; (("/usr/share/guile/2.0" "/usr/share/guile/site/2.0" "/usr/share/guile/site" "/usr/share/guile"))
>> --8<---------------cut here---------------end--------------->8---
>
> I can confirm half of it :-)
>
> I mean: the double entry "foo" for %load-path in your first result
> above doesn't happen for me. Could that be a typo?

My report was partially correct indeed.  There are two added entries in
‘%load-path’ with Guile from Debian testing:

$ guile --version
guile (GNU Guile) 2.0.11
Packaged by Debian (2.0.11-deb+1-10+b1)
Copyright (C) 2014 Free Software Foundation, Inc.

but only one with guile master:

$ meta/guile --version
guile (GNU Guile) 2.1.2.191-6788f
Copyright (C) 2016 Free Software Foundation, Inc

> As for the strangely different behaviour when running pre-compiled
> (old has %load-path's old value) and compiling (old has %load-path's
> value after (add-to-load-path ...) yes, that happens to me too, on
>
>   tomas@rasputin:/tmp$ guile --version
>   guile (GNU Guile) 2.0.11.133-d680
>   Copyright (C) 2014 Free Software Foundation, Inc.
>
> Looks like a bug to me.

Thanks for your answer.

-- 
Mathieu Lirzin