[Info-vax] VMS x86-64 compilers

[Craig A. Berry]

On 11/16/23 2:27 PM, Dan Cross wrote:
> In article <tDu5N.98763$YBDd.93660 at fx09.ams4>,
> Mark Daniel  <mark.daniel at wasd.vsm.com.au> wrote:
>> On 17/11/2023 06:20, Dan Cross wrote:
>> [snip]
>>> Why is it doing that?  I'd imagine inline assembler would be the
>>> most likely culprit, but I'm guessing there.  I wonder if you
>>> can get the compiler to emit an assembler listing?
>>
>> Excellent suggestion but unfortunately no.  The compile must quit very
>> early.  The object file has zero content precluding
>> ANA/OBJECT/DISASSEMBLE and while CC/LIST/MACHINE seems to be working
>> with this release the .LIS is similarly empty.
> 
> I'm mildly surprised by this: I'd imagine a compiler invocation
> equivalent to `clang -S` on a Unix-y system would quite before
> object generation; here, you just want to see what instructions
> the compiler would generate without it actually trying to create
> object code.  I wonder if `CC/LIST/MACHINE/NOOBJECT` will do it?
> 
> You definitely ought to be able to get it to generate LLVM byte
> code (which happens well before target instruction selection,
> let alone object code generation) which may give some clues as
> to what's going on.

According to the known restrictions section in the release notes for the
field test compiler:

"The /MACHINE_CODE qualifier currently is ignored. As a
temporary workaround, you can use the
ANALYZE/OBJECT/DISASSEMBLE command."

Of course if you can't get an object file, that workaround ain't gonna work.