[Info-vax] Userland programming languages on VMS.

[George Cornelius]

Bill Gunshannon <bill.gunshannon at gmail.com> wrote:
> On 1/28/22 14:46, Arne Vajh?j wrote:
>> On 1/28/2022 12:37 PM, John Reagan wrote:
>>> On Friday, January 28, 2022 at 8:51:57 AM UTC-5, Arne Vajh?j wrote:
>>>> On 1/28/2022 4:06 AM, cao... at pitbulluk.org wrote:
>>>>> On Friday, January 28, 2022 at 6:29:10 AM UTC, Steven Schweda wrote:
>>>>>>> Which I do not consider exotic.
>>>>>> Sure, fine, but look at the results from the current blend of (what
>>>>>> are, I assume) defaults. Whether or not better results are so "easy",
>>>>>> the existing situation (mess) is the existing situation (mess).
>>>>>>
>>>>>> As I said, "unrealistic". That was an inference, not a postulate.
>>>>>
>>>>> Aren't C/C++ the only VMS languages capable of using the full 64 bit 
>>>>> address space?
>>>>> Perhaps some others are (partially) capable but it doesn't look at 
>>>>> all convenient.
>>>>> Pascal has IADDRESS64 in addition to IADDRESS but why bother to call 
>>>>> a _64 system service when you can't really do much else with it?
>>>> I believe Fortran supports usage of P2 space.
>>>>
>>> Fortran lets you allocate COMMON in P2 and it has the CDEC$ POINTER64 
>>> (or however it is spelled)
>>> attribute.?? You can have "top level" 64-bit pointers but you can't 
>>> get 64-bit pointers as fields in a structure.
>> 
>> Real Fortran programmer does not use pointers.
>> 
>> :-)
>> 
>> Example with common:
>> 
>> $ type f64.for
>>  ????? program f64
>>  ????? implicit none
>>  ????? real*8 x(10),y(10)
>>  ????? common /cx/x
>>  ????? !DEC$ATTRIBUTES ADDRESS64::cy
>>  ????? common /cy/y
>>  ????? write(*,'(1x,z16.16)') %loc(x)
>>  ????? write(*,'(1x,z16.16)') %loc(y)
>>  ????? end
>> $ for f64
>> $ link f64
>> $ run f64
>> 0000000000040000
>> 0000000080000000
>> 
> 
> I ran that thru every FORTRAN compiler I had.  Sorry, it's not
> FORTRAN.

Works on Eisner.

$ show sys/noproc
OpenVMS V8.4-2L2  on node EISNER   29-JAN-2022 [...]

Here's the memory layout synopsis from a linker map:

Virtual memory allocated:                         00010000 0005FFFF 00050000 (327680. bytes, 640. pages)
64-Bit Virtual memory allocated:                  00000000 00000000 00000000
                                                  80000000 80010000 00010000 (65536. bytes, 128. pages)

The example, though, shows too small an allocation to escape 32 bit address space.

George