Re: Problems with handicapped 'bash' from glibc package

[ludo@gnu.org (Ludovic Courtès)]

Mark H Weaver <mhw@netris.org> skribis:

> ludo@gnu.org (Ludovic Courtès) writes:
>
>> Mark H Weaver <mhw@netris.org> skribis:
>>
>>> ludo@gnu.org (Ludovic Courtès) writes:
>>>
>>>> Mark H Weaver <mhw@netris.org> skribis:
>>>>
>>>>> The 'bash' in the glibc package is handicapped in at least two ways:
>>>>>
>>>>> * It can't set the locale, because it looks for locales in
>>>>>   /nix/store/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-glibc-intermediate-2.18-locales
>>>>>
>>>>> * It can't look up anything from NSS, such as passwd data, because it
>>>>>   tries to load the modules from
>>>>>   /nix/store/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-glibc-intermediate-2.18
>>>>>
>>>>> There are two problems that need to be addressed, I think:
>>>>>
>>>>> * Users could easily end up with this handicapped 'bash' as their
>>>>>   primary bash, if they installed (or upgraded?) 'glibc' since the last
>>>>>   time I installed 'bash'.  This happened to me, for example.
>>>>
>>>> I realized that this particular problem is easily solved by moving
>>>> glibc’s bash away from $bindir, for instance to $libexecdir.
>>>>
>>>> I’m trying it out locally, and plan to commit to core-updates if
>>>> everything works as expected (hopefully as the last core-updates
>>>> change.)
>>>>
>>>> Thoughts?
>>>
>>> Hmm.  We need a more intelligent union.scm anyway,
>>
>> Agreed, but that’s a separate issue.
>>
>> Having it in $bindir also means that patch-shebangs can pick it up,
>> which is usually not what we want.
>>
>> So I think it really makes sense to move it out of sight.
>
> Well, that's sweeping it under the rug, when actually this broken bash
> should never be used for anything except perhaps during the bootstrap.
>
> The fact is, we have broken 'system' and 'popen' functions in Guix.
> For example:
>
> mhw:~$ cat foo.c
> #include <stdlib.h>
>
> int
> main (int argc, char *argv[])
> {
>   return system ("echo Hello world");
> }
>
> mhw:~$ gcc -o foo foo.c
> mhw:~$ ./foo
> sh: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
> Hello world

Yes, understood.

> Our glibc should not use a broken bash.  It would also be nice if the
> bash used by glibc was linked with the same glibc, so that we only need
> one copy of glibc in memory.  So there's a circular dependency here.
>
> I think we need a better way of dealing with circular dependencies in
> general, but in the meantime, I think we should build the final glibc
> and bash as two outputs from the same derivation, so that they can refer
> to each other.
>
> What do you think?

Again, I definitely agree.  We discussed ways to do it here:

  https://lists.gnu.org/archive/html/guix-devel/2014-02/msg00145.html

Someone just needs to do it.  :-)  We could schedule it for the next
core-updates round, WDYT?

Note that technically, it cannot be two separate outputs because outputs
currently cannot have circular references (and it wouldn’t buy us much
anyway.)

Ludo’.