svn commit: r452962 - head/math/libRmath

[Tijl Coosemans]

On Sat, 28 Oct 2017 20:56:38 -0300 Joseph Mingrone <jrm at FreeBSD.org> wrote:
> Tijl Coosemans <tijl at FreeBSD.org> writes:
>> It's not a gfortran problem.  It's a kernel or libthr problem.  You
>> can work around it by avoiding the combination of recycled thread
>> stacks and exception handling done by ports libgcc_s.  When you
>> switched from curl to wget you avoided threads and that fixed the
>> problem.  Switching to flang avoids ports libgcc_s and that also
>> fixes the problem, but it's not necessary to go this way.  You could
>> probably go back to curl if you build it with the CARES option instead
>> of THREADED_RESOLVER.
> 
> I missed this paragraph last time around.
> 
> It's not really a switch to wget.  We just pull it in as RUN_DEPENDS
> when gfortran is on.  R still defaults to downloading packages with
> curl.  Users can create/edit configuration to switch to wget, which
> is not a big deal, but not ideal.  I've copied sunpoet@, the
> maintainer of ftp/curl.  sunpoet@, what do you think about switching
> ftp/curl's default to c-ares instead of THREADED_RESOLVER to work
> around this problem (until there are fixes for the threading problem
> that is triggered with ports libgcc_s)?

The fix for this was committed to FreeBSD head and stable/11 and a
workaround has been added to the lang/gcc ports now, so it should be
possible for math/R to use curl again, with THREADED_RESOLVER option.

So I'd like to propose the following compromise:
We keep USES=fortran:gcc and fortran:flang but also introduce
DEFAULT_VERSIONS=fortran and let plain USES=fortran choose the Fortran
compiler based on that.  Then math/R can provide a flang option that
sets USES=fortran:flang when on, and USES=fortran when off.  So the
description of the option would be something like "Use flang instead
of the default Fortran compiler".  The default for this option would
be off, also on amd64.