BUG: bash 3.0-7 breaks rebaseall

BUG: bash 3.0-7 breaks rebaseall

[John Whitley]

Bash 3.0-7 dynamically links against several libraries (e.g.  
cygiconv-2).  This makes it impossible to run the rebaseall script,  
which must be run from a statically linked bash shell (from cmd.exe,  
not rxvt, etc.) so that no DLLs are in use when the underlying rebase  
tool runs.

This, in turn, affects Apache, Perl, and Python, three cygwin apps  
that are known to be affected by the rebase problem (per /usr/share/ 
doc/Cygwin/rebase-2.3.README).

The workaround is to revert bash to 2.05b-17, at least to do the  
rebaseall.

-- John Whitley



--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

Re: BUG: bash 3.0-7 breaks rebaseall

[Brian Dessent]

John Whitley wrote:

> Bash 3.0-7 dynamically links against several libraries (e.g.

Thanks for the report, but this has already been noted and discussed
recently in other threads.  Several solutions have been proposed but I
think the jury is still out on how to handle it.

The main issue is that no matter how you implement the 'rebaseall'
concept, you still won't be able to run it from a standard bash command
prompt and have it modify the in-use DLLs.  I think statically linking
bash or providing a second version of bash that is statically linked
have both been vetoed.

It seems that the concensus now is that we need to get
--enable-auto-image-base working properly (or, at least enable it for
those packages that are prone to ImageBase issues) so that the need to
manually rebase anything is removed.

Brian

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

Re: BUG: bash 3.0-7 breaks rebaseall

[Eric Blake]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

According to Brian Dessent on 7/13/2005 7:21 PM:
> Thanks for the report, but this has already been noted and discussed
> recently in other threads.  Several solutions have been proposed but I
> think the jury is still out on how to handle it.
> 
> The main issue is that no matter how you implement the 'rebaseall'
> concept, you still won't be able to run it from a standard bash command
> prompt and have it modify the in-use DLLs.  I think statically linking
> bash or providing a second version of bash that is statically linked
> have both been vetoed.

Actually, I am against a statically linked /bin/sh as bash, because
/bin/sh should not be any less full-featured than /bin/bash, or we are no
better off than having ash again with regards to the sh != bash complaints
on the list.  But I am not entirely opposed to a statically linked
/usr/sbin/sh, a statically-linked version of bash with all interactive
features stripped (ie. no aliases, no history, no syntax extensions, ...).
 Normal PATHs do not put sbin at the front (or maybe I could name it
/usr/sbin/bash-lite to be explicit and unique).  But rebaseall would then
have a known good static shell, and still break the dependence on ash.  By
the way, since sbin is not mounted by default, would such a reduced shell
belong better as /sbin/sh or /usr/sbin/sh?

- --
Life is short - so eat dessert first!

Eric Blake             ebb9@byu.net
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (Cygwin)
Comment: Public key at home.comcast.net/~ericblake/eblake.gpg
Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org

iD8DBQFC1d/N84KuGfSFAYARAoiMAKCDOW6G5KHGWWchk8sGxD0c7TVgtACgiIJ2
q7Y/h3LxJmuwtwGahORs+iI=
=bibZ
-----END PGP SIGNATURE-----

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

Re: BUG: bash 3.0-7 breaks rebaseall

[Igor Pechtchanski]

On Wed, 13 Jul 2005, Eric Blake wrote:

> According to Brian Dessent on 7/13/2005 7:21 PM:
> > Thanks for the report, but this has already been noted and discussed
> > recently in other threads.  Several solutions have been proposed but I
> > think the jury is still out on how to handle it.
> >
> > The main issue is that no matter how you implement the 'rebaseall'
> > concept, you still won't be able to run it from a standard bash command
> > prompt and have it modify the in-use DLLs.  I think statically linking
> > bash or providing a second version of bash that is statically linked
> > have both been vetoed.
>
> Actually, I am against a statically linked /bin/sh as bash, because
> /bin/sh should not be any less full-featured than /bin/bash, or we are no
> better off than having ash again with regards to the sh != bash complaints
> on the list.  But I am not entirely opposed to a statically linked
> /usr/sbin/sh, a statically-linked version of bash with all interactive
> features stripped (ie. no aliases, no history, no syntax extensions, ...).
>  Normal PATHs do not put sbin at the front (or maybe I could name it
> /usr/sbin/bash-lite to be explicit and unique).  But rebaseall would then
> have a known good static shell, and still break the dependence on ash.  By
> the way, since sbin is not mounted by default, would such a reduced shell
> belong better as /sbin/sh or /usr/sbin/sh?

This must be by now approximately the third iteration of the discussion.
A separate statically-linked shell as the interpreter shell for rebaseall
will not work, simply because that will need to be invoked from another
shell (which would most likely be bash).  So nothing's gained, since the
bash process will still be running.

Let's face it, rebaseall as it's written now relies on there being no DLLs
loaded (read: locked) besides cygwin1.dll.  If there are, it fails.
Running rebaseall from bash (as it currently stands) will cause other DLLs
to be in memory -- thus, rebaseall cannot be run from bash.  If rebaseall
is invoked from a DOS shell as 'someshell rebaseall', then 'someshell'
needs to be statically linked to every library except cygwin1.dll.

If we go to the trouble of compiling a special shell for rebaseall, we
might as well rewrite it in C, with about as much investment of time and
effort.  Since, as was mentioned before, automatic selection of image
bases won't work, so maybe it's time to bite the bullet and write it now.
	Igor
P.S. We don't have anything in /sbin now, and I don't think this is the
time to start.
-- 
				http://cs.nyu.edu/~pechtcha/
      |\      _,,,---,,_		pechtcha@cs.nyu.edu
ZZZzz /,`.-'`'    -.  ;-;;,_		igor@watson.ibm.com
     |,4-  ) )-,_. ,\ (  `'-'		Igor Pechtchanski, Ph.D.
    '---''(_/--'  `-'\_) fL	a.k.a JaguaR-R-R-r-r-r-.-.-.  Meow!

If there's any real truth it's that the entire multidimensional infinity
of the Universe is almost certainly being run by a bunch of maniacs. /DA

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/