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

[Julien Fischer]

On Mon, 18 Apr 2016, Zoltan Somogyi wrote:

>
>
> On Tue, 05 Apr 2016 00:37:24 +1000 (AEST), "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
>> > I've been checking some compilation model combinations.  I found that it was
>> > okay with:
>> > 
>> >     $ ./choose_grade thread_safe=thread_safe debug=debug
>> >     $ ./choose_grade thread_safe=thread_safe deep_prof=deep_prof
>> > 
>> > AFAIK these don't work with multiple threads.  Is there a missing
>> > constraint?
>>
>> I think you are right: neither the debugger nor the deep profiler
>> will work correctly in the presence of multiple threads, so neither
>> the current compiler nor the grade library should accept either grade.
>> I will add the missing constraints, though I will wait until we think
>> we have identified all the other missing constraints as well, since
>> that reduces redundant work. Thanks.
>
> To reflect these constraints in the grade structure, I also need to know
> whether we support the combination of thread safety with either
> (a) mprof-style profiling, using either the llds or the mlds backend, and

No, you cannot mix multithreaded code and mprof-style profiling.

> (b) the source-to-source debugger for hlc grades.

Ditto for this.

> I don't know the answers to those questions. Does anyone else?

Yes ;-)

In general, all of the above combinations might do "something", but they
certainly don't work intentionally.

Julien.