RE: 3rd problem: Bug cross-compiling bash (with buildroot): mkbuiltins uses config.h

[kus Kusche Klaus]

> kus Kusche Klaus wrote:
> >>>The same problem occurs when compiling psize.c:
> >>>
> >>>It is compiled for the host with the defines in "config.h",
> >>>which are valid for the target environment only.
> >>>
> >>>Moreover, running "psize.c" on the host is irrelevant anyway:
> >>>The size of a pipe on the host is not the same as the size of
> >>>a pipe on the target...
> >>
> >>Luckily, this provides only a last-ditch default.  Just about every
> >>system should have the posix defines that provide the correct value.
> >>
> >>Chet
> > 
> > Well, if it is a last-ditch default only, than it is even worse that
> > its compilation causes the whole bash build to fail:
> > psize.c does not compile at all with the wrong config.h included
> > on my system, and make stops.
> 
> The problem is that these auxiliary C programs (mkbuiltins, 
> psize, etc.)
> are non-trivial enough to have the same sort of portability 
> problems as
> any other program.  Arguably the inclusion of config.h is 
> imperfect, but
> there's not really a good solution, and including config.h solves the
> problem in the vast majority of cases.

In the end, two different configure runs would be needed, 
generating two different config.h:

One for the host compiler and the host include files,
one for the cross compiler and the target include files.

I believe I've seen some packages doing that, but I can't remember
which packages and how they did it.

-- 
Klaus Kusche                 (Software Development - Control Systems)
KEBA AG             Gewerbepark Urfahr, A-4041 Linz, Austria (Europe)
Tel: +43 / 732 / 7090-3120                 Fax: +43 / 732 / 7090-6301
E-Mail: kus@keba.com                                WWW: www.keba.com