[Bug fortran/56226] New: Add support for DEC UNION and MAP extensions

[russelljbrennan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56226



 Bug #: 56226

   Summary: Add support for DEC UNION and MAP extensions

Classification: Unclassified

   Product: gcc

   Version: unknown

Status: UNCONFIRMED

  Severity: enhancement

  Priority: P3

 Component: fortran

AssignedTo: unassig...@gcc.gnu.org

ReportedBy: russelljbren...@gmail.com





Porting old f77 code for use with gfortran is fairly straightforward, even for

most extensions.  The UNION and MAP extensions thusfar prove impossible to port

without modifying the UDT interface.  Existing compilers can candle these

extensions (intel ifort and portland group) but there is no open source

alternative available afaik.  UNIONs and MAPs are widely lamented exclusions of

the later fortran standards.  Addition of support for these extensions would

facilitate automated conversion of much existing code to gfortran-compatible

code.

[Bug fortran/56226] Add support for DEC UNION and MAP extensions

[russelljbrennan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56226



--- Comment #2 from russelljbrennan at gmail dot com 2013-02-07 13:31:16 UTC ---

It seems to me that the UNION/MAP pair is analogous to a basic form of a c/c++

union of structs.  Could the corresponding code not be ganked and fitted to

this application?  I did notice in the IBM link that you provided that unions

are only defined in an enclosing record structure... RECORDs and STRUCTUREs are

easily replace with UDTs.  It would make sense to me to allow UNION/MAP inside

UDTs as well as RECORDs and STRUCTUREs.

[Bug fortran/56226] Add support for DEC UNION and MAP extensions

[russelljbrennan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56226



--- Comment #4 from russelljbrennan at gmail dot com 2013-02-08 01:03:12 UTC ---

>From a memory standpoint yes, union/map can be replaced by equivalence.  From

an API standpoint it cannot afaik.  A suggestion for the former lies here

http://stackoverflow.com/questions/14733238/convert-fortran-dec-union-map-extensions-to-anything-else

[Bug fortran/56226] Add support for DEC UNION and MAP extensions

[russelljbrennan at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56226

--- Comment #10 from russelljbrennan at gmail dot com ---
Thanks for this Fritz!  Should make a lot of people's lives much easier.