[Patch, Fortran] PR57141 - fix using use-associated NULL() intrinsic

[Tobias Burnus]

The problem is that the procedure attributed is tried to be set to 
NULL() - but that's rejected because null() is use associated. I am not 
sure whether this is the cleanest patch, but I think it should be fine.

Build and regtested on x86-64-gnu-linux.
OK for the turnk?

PENDING PATCHES:
- http://gcc.gnu.org/ml/gcc-patches/2013-04/msg01817.html
- http://gcc.gnu.org/ml/gcc-patches/2013-04/msg01787.html

Tobias
-------------- next part --------------
A non-text attachment was scrubbed...
Name: use-null.diff
Type: text/x-patch
Size: 1098 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/fortran/attachments/20130503/0bd72f75/attachment.bin>