[m-rev.] the grade library is ready for review

[Julien Fischer]

On Tue, 19 Apr 2016, Zoltan Somogyi wrote:

> On Tue, 19 Apr 2016 11:59:06 +1000 (AEST), Julien Fischer <jfischer at opturion.com> wrote:
>> There's no such thing as non-threaded C#, Java (or indeed Erlang) grade.
>
> Actually, as long as thread.m does not implement spawn for Erlang,
> Mercury-generated Erlang code is effectively non-threaded, or at least
> that is what I understood from Peter's last mail on this topic.

What Peter said.  I don't use the Erlang backend aside from ensuring it
still compiles as part of the ROTD builds.

>>> (2) Is trailing compatible with trailing, on either the llds or mlds backend?
>>> My guess is no and no.
>>
>> Is trailing compatible with trailing?  (I bloody well hope so!)
>> You presumably meant something else there.
>
> Yes. I meant: is trailing compatible with thread safety, in llds or mlds?

Thread-local trailing in the was implemented back in 2007 (commit
1d50d41).  However, trailing is not currently supported in the presence
of parallel conjunction.  I don't recall what the compiler currently
does in an .par.trseg grade if it encounters a parallel conjunction.

Julien.