Re: [FYI] {maint} testsuite: be more cross-compile friendly

[Stefano Lattarini]

On Sunday 15 May 2011, Stefano Lattarini wrote:
> On Sunday 15 May 2011, Ralf Wildenhues wrote:
> > * Stefano Lattarini wrote on Sun, May 15, 2011 at 03:48:43PM CEST:
> > > I've applied the attached patch to 'maint', rather than to 
> > > 'testsuite-work',
> > > only to make it easier to (potentially) backport tests for future 
> > > bugfixing.
> > > I plan to check in fixes tests that don't currently work in cross-compile
> > > mode only in the 'testsuite-work' branch, to avoid excessive churn on
> > > 'maint' and 'master'.
> > 
> > > Subject: [PATCH] testsuite: be more cross-compile friendly
> > > 
> > > * tests/defs.in (cross_compiling): New subroutine.
> > > (am__tool_prefix): New internal variable.
> > > (gcc, g++, gcj): Force the use of the correct "tool prefix"
> > > when cross compiling.
> > > (gfortran, g77, non-cross): New requirements.
> > 
> > > --- a/tests/defs.in
> > > +++ b/tests/defs.in
> > > @@ -148,6 +148,23 @@ fail_ () { warn_ "$me: failed test: $@"; Exit 1; }
> > >  skip_ () { warn_ "$me: skipped test: $@"; Exit 77; }
> > >  framework_failure_ () { warn_ "$me: set-up failure: $@"; Exit 99; }
> > >  
> > > +# cross_compiling
> > > +# ---------------
> > > +# Tell whether we are cross-compiling.  This is especially useful to skip
> > > +# tests (or portions of them) that requires a native compiler.
> > > +cross_compiling ()
> > > +{
> > > +  test x"$host_alias" != x
> > > +}
> > 
> > FWIW, this condition isn't the same as the one configure uses in order
> > to determine whether cross compilation is enabled or not.  Is that an
> > oversight or on purpose?
> >
> Oversight, sorry (it's basically the first time I'm doing cross-compilation,
> if that's any excuse).  What condition should I use instead?
>
OK, we could use the `$cross_compiling' variable inside configure.ac, but
obviously not inside `tests/defs'.

My idea is that a simple:
 $ make check host_alias='...'
should suffice to run the testsuite in cross-compile mode -- and this is
what I'm succesfully doing right now.

But maybe it should be safer and more correct to follow the configure logic
more closely when determining whether cross-compilation is in effect; i.e.,
our definition of `cross_compiling' should become something like:

  host_alias=${host_alias-'@host_alias@'}
  build_alias=${build_alias-'@build_alias@'}
  cross_compiling ()
  {
    test x"$host_alias" != x && test x"$build_alias" != x"$host_alias"
  }

WDYT?

Regards,
  Stefano