[mpi-21] Ballot 4 proposal: fix attribute example 4.13

[Jeff Squyres]

Per http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/ 
, the errata item entitled "Error in Example 4.13 in MPI-2 (Use of  
Attributes in C and Fortran)".  I believe that this errata item  
supersedes the errata item "Interlanguage use of Attributes".

See the mail discussing:

http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/discuss/attrcandf/

Proposal:

Change MPI-2:4.12, p58:36 from:
   IF (val.NE.5) THEN CALL ERROR
to
   IF (val.NE.address_of_i) THEN CALL ERROR

Rationale:

MPI-2:4.12 p58:12-13 and 16-18 clearly state that if an attribute is  
set by C, retrieving it in Fortran will obtain the address of the  
attribute.

See the mails for more discussion, including an exhaustive list of  
what happens for each of the 9 possibilities of setting and getting  
attribute values between the different languages.


-- 
Jeff Squyres
Cisco Systems