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Re: pbulk bootstrap: `awk` running into FP overflow during bison build (Grater picture: How to bootstrap pkgsrc / pbulk?)




> On Aug 7, 2023, at 12:49 PM, Johnny Billquist <bqt%softjar.se@localhost> wrote:
> 
> On 2023-08-07 13:34, Anders Magnusson wrote:
>> Den 2023-08-07 kl. 13:31, skrev Maciej W. Rozycki:
>>>   Overall I think we ought to support both, but it might be a bit tricky on
>>> the toolchain side, as it's an ABI issue to sort out.  Did any machine
>>> actually implement H_floating in hardware, or was it only ever emulated?
>> The 780 had H-float in hardware.  Actually, it had all instructions in hardware (microcode).
> 
> The 780 had H-float as an option, I think. The 730 might always have had it, but otherwise the default answer for me for any of these questions is always the 86x0. It had everything in hardware (well, ok, microcode), except things like vector instructions, which hadn't been defined when the machine was sold. Fairly sure it was the machine with the most of all VAX stuff done in hardware.
> 
>  Johnny

DEC Std 032, the VAX standard, says (appendix B) that the 730 has G and H standard, while the 750 and 780 have an option to provide G and H float.  I assume that option was a later addition since G/H float don't appear in the original VAX handbooks.

	paul



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