[libgfortran,patch] Add compiler check when configuring libgfortran

[FX Coudert]

>> checking whether the GNU Fortran compiler is working... no
>> configure: error: GNU Fortran is not working; please report a bug in
>> http://gcc.gnu.org/bugzilla, attaching
>> /home/fxcoudert/svn/debug3/ibin/i686-pc-linux-gnu/libgfortran/ 
>> config.log
>
> Perhaps we can tell the user to first look into the failure?  The  
> error
> message could mention a few hints about GMP and MFPR too.

On 4.2, yes. On 4.3, GMP or MPFR mislinking would now show up earlier  
than that, so there's no need for a specific error message.

>> Bootstrapped and tested on i686-linux. OK for mainline? Would it  
>> be OK
>> to backport this to 4.2, a few weeks after it has been commited to
>> mainline? (I think it's an annoying bug for users compiling on  
>> unusual
>> platforms or using unusual configurations).
>
> unusual == non-Linux I presume?  Solaris is definitely not unusual.
> I'd second putting this on the 4.2 branch, rather sooner than later.

That would be "unusual configuration", that is, neither system libs  
nor in-tree (as will soon be possible). Otherwise, no, Solaris is not  
unusual (although it's not used much for scientific calculation  
anymore, in my field anyway).

FX