[m-rev.] for review: Add a `pregen' grade component.

[Julien Fischer]

On Wed, Mar 20, 2013 at 11:31 AM, Paul Bone <paul at bone.id.au> wrote:
> On Wed, Mar 20, 2013 at 11:19:42AM +1100, Julien Fischer wrote:
>> On Tue, Mar 19, 2013 at 3:16 PM, Peter Wang <novalazy at gmail.com> wrote:
>>
>> >> > During installation, if required, the pre-generated C source files are
>> >> > used to build and install a Mercury compiler _in a .pregen grade_.
>> >> > Then it is used to install the libraries _in non-.pregen grades_,
>> >> > so that configured settings have their usual effect.
>> >>
>> >> That of course presupposes that the pregen version of the compiler is
>> >> statically linked against the Mercury libraries (i.e.
>> >> --mercury-linkage=static).  It's probably not worth supporting a pregen version
>> >> of the Mercury compiler that is linked against the shared version of the Mercury
>> >> libraries.
>> >
>> > This change doesn't yet block installation of the .pregen grade,
>> > so that should actually work for now.
>>
>> Could we install just the pregen version of the library with
>> --enable-minimal-install?
>> It's not as though you actually use a --enable-minimal-install version
>> of the compiler
>> for anything other than bootstrapping a new Mercury anyway.
>>
>
> Not true.  Our users are interested in 'just trying Mercury'.  If they can
> get installed quickly via --enable-minimal-install then they'll do this just
> so they can try Mercury.

Installing just the pregen grade is not going to prevent anyone from just
trying Mercury either.  Mind you, my intention when I added it was that
it was intended for bootstrapping.  And that's exactly what the documentation
for it says:

#          The option --enable-minimal-install will install only the minimal
#          system that is required in order to bootstrap the Mercury compiler.

...

> As an asside, the best way to reduce TTH would be to provide binaries and
> include Mercury in OS distributions.  (Yes. I'll do this some-day).

Indeed.

Cheers,
Julien.