Re: fortran.m4 _AC_FC_LIBRARY_LDFLAGS

[Ralf Wildenhues]

Hi Jim,

thanks for the report.

On Wed, Jun 08, 2011 at 10:25:13AM -0600, Jim Edwards wrote:
> I think that I've found a bug in this function,  I am using pgf90 10.3-0
> and the -v flag is producing a line which includes a flag -list which is
> then interpreted as a library and causes a failure later when it trys to
> link.
> 
> In the function I found:
> 
>       # Ignore these flags.
>     -lang* | -lcrt*.o | -lc | -lgcc* | -lSystem | -libmil | -little \
>       |-LANG:=* | -LIST:* | -LNO:* | -link )
>       ;;
> 
> 
> And the obvious thing to do is add -list to this list.

And that is IMVHO the correct fix here, too.  Would love to be beaten to
pushing the fix though.

>  I did that and it
> solves the problem.   But this list seems really kludgey to me - wouldn't it
> be better to test link with all of the -lwhatever
> flags and keep the ones that pass that test?

Well, the problem is that some of the above won't cause failures in every
case, for example -lc and -lgcc.  So we might not notice that we should
drop these flags.  Also, trying to drop them one by one, or adding them
one by one is not necessarily sufficient to find a suitable set, as there
may be interdependencies between the libraries.  The last point is mostly
moot on all modern systems, due to working interdependent library linking.

Cheers,
Ralf