historical question

[jayb]

I was recently explaining to a colleague why I chose Intel Fortran for a legacy application that will (assuming we receive the expected funding) undergo a modernization process.  I was missing one historical piece of information.  I know that Intel Fortran is descended from DEC Fortran.  But there is also an HP Fortran, which supports HP's proprietary operating systems, including (Open)VMS.  Was there a point at which a single compiler diverged into the two products we see today?  Is there still sharing of effort/code among the two companies?

JayB

[Steven_L_Intel1]

Here's the progression of the code base:

• DEC Fortran 90 for RISC ULTRIX (MIPS processors) This was not derived from VAX Fortran 77.
• DEC Fortran 90 for DEC OSF/1, Tru64 UNIX, OpenVMS Alpha, Windows NT Alpha and DIGITAL Visual Fortran
• DEC Fortran 90 renamed Compaq Fortran (and Compaq Visual Fortran) in 1999
• In August 2001, Intel acquires the Compaq Fortran development team
• In September 2001, HP buys Compaq
• 2001-2003, the Fortran team (now with Intel) continues maintenance on the Compaq compilers while developing a new version of Intel Fortran.
• 2001-2006 (or thereabouts), Intel provides HP with consultation and fixes for the OpenVMS and Tru64 compilers (since renamed HP Fortran), but not new language features
• 2004 - Intel [Visual] Fortran 8.0 released, combining the DEC/Compaq Fortran "front-end" (language syntax and semantics) with the Intel optimizer and code generator

There is no longer any sharing between the two companies, and HP did not pick up new language feature development. To the best of my knowledge, the HP Fortran for OpenVMS today is pretty much a snapshot of where Compaq Fortran was in 2001 as far as features are concerned. Note that HP Fortran for HPUX is an entirely different thing.

[TimP]

As Steve said, intel worked with HP on their Fortran for itanium (including hpux). I'm not aware of any remaining direct descendants of Hpux Fortran.

[Steven_L_Intel1]

To clarify Tim's comment - The HPUX Itanium compiler has nothing shared with the DEC Fortran codebase, using HP's (non-DEC heritage) front-end and the Intel code generator.  HP Fortran for OpenVMS Itanium uses the DEC-heritage Fortran front-end and the DEC/Compaq "GEM" optimizer/code generator.

[mecej4]

I remember that some early versions of Intel Fortran (versions 4 to 7?) had components from EPC (Edinburgh Portable Compiler). There was also a debugger called EDB, and I don't know if that came from EPC, too.

What happened to those components?

[Steven_L_Intel1]

I don't know about EDB but indeed the earlier Intel Fortran compilers were based on a front end from EPC. Those components are gone.