3 Aug
2021
3 Aug
'21
7:04 a.m.
Recompiling Forth was always such a trivial process, there was no reason to not recompile
itself using itself. It was also a good check of the output. One could compare the output
and check any differences to ensure that they were intended. One could run it twice again
as a check as well.
It wouldn't always ensure that it had no errors but would validate that only the
intended changes were there. Some of the early Forths had bugs in some of the math
operations.
I recall reading about such errors in the groups and recompiling the version I had to fix
such errors.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Stefan Skoglund via
cctalk <cctalk at classiccmp.org>
Sent: Tuesday, August 3, 2021 1:33 AM
To: Gavin Scott <gavin at learn.bio>; General Discussion: On-Topic and Off-Topic
Posts <cctalk at classiccmp.org>; Fred Cisin <cisin at xenosoft.com>
Subject: Re: Compilers and languages (Was: Help reading a 9 track tape
m?n 2021-08-02 klockan 20:00 -0500 skrev Gavin Scott via cctalk:
Another interesting question is whether the currently shipping
version
of a language written in itself was compiled using the same version
of
itself or the previous version. I recall HP compilers generally being
built with the previous version (at least the last time I looked
which
was probably in another century).
GNAT itself was written in Ada from the beginning, though the backend
is part of gcc so partly rewritten to support some Ada constructs
(which also benefitted C++).
From the beginning I believe they used the Alsys
compiler until
GNAT was able to compile itself.