[rescue] compiling old software re: emacs on SunOS 4.1.4

[Stefan Skoglund]

tis 2018-05-29 klockan 19:49 +0200 skrev Romain Dolbeau:
> 2018-05-29 16:25 GMT+02:00 Doug McIntyre <merlyn at geeks.org>:
> > I would say that 90% of the code out there could still compile on
> > SunOS
> 
> Having tried to get a half-decent web browser in S7/S8 on v7 & v8
> hardware, I strongly disagree.
> Most OSS nowadays is heavily reliant on a multitude of libraries,
> many
> of which are rife with linuxisms, or assume a much, much newer libc
> with new functions.
> They are also assuming that dereferencing a pointer is always OK,
> without caring for data alignment - which is causing a lot of grief
> to
> the Debian/sparc64 people among others.
> 
> Also - anything even indirectly reliant on recent C++ is pretty much
> a
> no-go on v7/v8 HW, you need v8+/v9 - UltraSPARC, so no SunOS.
> C++ requires some atomic updates, and the GCC interface (not sure
> about the language itself) assumes an atomic fetch-and-add is
> available.
> Which doesn't exist in SPARC prior to v8+/v9. You can fake it with a
> global lock (or a hashed lock, if you need ultimate speed on those
> hot
> SM512 ;-) ) for intra-process locking (been there, done that), but
> for
> inter-process it's a nightmare to emulate properly.
> 
> I love SPARC, but no matter how awesome the work of those who did
> make
> parallel SPARC machine (yeah Solbourne!), the designer of SPARC
> didn't
> properly specify the atomic instructions in v7/v8. You really, really
> want atomic fetch-and-add in real life. Not that it was obvious at
> the
> time - for a lock, SPARC has enough support.
> 
> Cordially,
> 

ldstub (the atomic take-from-memory-deposit-in-register-store-a-value-
in-memory which doing bus-snooping) exists in supersparc (basically a
requirement for multiprocessor supersparc machines.)

C++ - a lot happened with regards to how to implement a lot of c++
semantics in the compilers around 1995-2000.

That web browsers from early 2000 is unworkable on sparcv8 and impotent
as a current web browser - well it says a lot of the changes in web
technologies between 1995 and 2008 or so