*ping* [Patch, fortran, RFC] Add warning for missing location information

[Thomas Koenig]

 > If something is found, a warning is issued.  I chose not to issue an
 > error because missing location information does not make a program
 > invalid.  The patch would cause testsuite regressions for changes
 > which cause missing location information, which is a good thing because
 > we want to catch missing locations as soon as they are (potentially)
 > introduced.

 > The checking is turned off if CHECKING_P is not defined, so it should
 > not slow down release compilers.

 > I used DK_NOTE here, but that is open to discussion.  Maybe it would be
 > better to define another warning class for this?

Ping?  Any comments?

> What do you think?  OK for trunk, or should something be done
> differently?
>
> Regards
>
>     Thomas
>