[M3devel] Downsides of Modula-3 ?

[Mika Nystrom]

I'm almost certain the problem is somewhere in the pthreads implementation
of M3 threads, which consists of a couple of files of C and M3 within
m3core.

    Mika

"Daniel Alejandro Benavides D." writes:
>Hi all:
>I'm more suspicious about the back needs over this programs, since Win32 pr=
>ograms have worked OK, have they? So I agree with you it's a matter of targ=
>et implementation (not UNSAFE world), but that's in m3gcc backend, isn't it=
>?
>Similarly your code could be fixed to uniprocessor semantics, so if this te=
>sts are OK either pthreads or embedded M3 threads this is a clear symptom o=
>f that UP semantics issue.
>In any case don't expect too many threads to do that correctly, since any e=
>xception in them can't be managed by Modula-3 RT (by language definition) b=
>ut at most in m3gcc semantics I believe so. DECthreads had a nice mechanism=
> to wrap it to Modula-3 style semantics so it could be easier to offer that=
> in a internal CM3 API.
>Thanks in advance
>
>
>--- El s=E1b, 21/4/12, Mika Nystrom <mika at async.caltech.edu> escribi=F3:
>
>> De: Mika Nystrom <mika at async.caltech.edu>
>> Asunto: Re: [M3devel] Downsides of Modula-3 ?
>> Para: "Jay K" <jay.krell at cornell.edu>
>> CC: m3devel at elegosoft.com
>> Fecha: s=E1bado, 21 de abril, 2012 18:36
>> Jay K writes:
>> >1) please elaborate=20
>>=20
>> >2) We don't use longjmp as much any more=3D2C but
>> get/set=3D
>> >/make/swapcontext on platforms that support them.And
>> where we do use longjm=3D
>> >p=3D2C we have a more portable use than before -- we no
>> longer hack on the jm=3D
>> >pbuf.There is a "trick" where you use sigsetstack or
>> some such to get the s=3D
>> >tack pointer into the jmpbuf.Look at the code and read
>> the paper referenced=3D
>> >. It is possible it didn't work on all platforms.=20
>> But anyway=3D2C see #1.We'=3D
>> >d really prefer to just use pthreads.Hm. I'd like to
>> look again at what pth=3D
>> >reads features we use -- I suspect pthreads/Win32 can
>> beabstracted more thi=3D
>> >nly and the Modula-3 code less-forked/more-shared. But
>> later..  - Jay > Fro=3D
>>=20
>> Sorry for the bad quote.  My mailer still lives in the
>> 7-bit world.
>>=20
>> In any case I was just mentioning as a problem with the
>> current Modula-3
>> implementation that the pthreads bindings are buggy.  I
>> would not (and
>> do not) use them for serious work.  And user threads
>> are, as we all know,
>> not ideal...
>>=20
>> Anybody who wants to investigate the matter can start by
>> running the thread
>> testing program in m3core/tests/thread ...  Main.m3 is
>> fairly well documented.
>>=20
>>      Mika
>>