[MLton] self-compiled mlton on redhat 9

[Stephen Weeks]

> > How much memory does your machine have?
> 2.4GHz Pentium with 1GB memory
...
> Ok I let the build run through. It compiles correctly, also all
> the regressions.
> Here are the times of the complete build:
> 994.87s user 138.22s system 15% cpu 2:01:49.77 total
> That's an awful long time, and as you can see, it spent most of
> the time thrashing around, and the computer was quite unresponsive
> during the time.

The user+sys is in the right ballpark for your machine.  I don't
understand why it is thrashing so badly.  By default the runtime
shouldn't use more than 80% of RAM, which is more than enough to do a
self compile on a 1GB machine.  Was anything else running
simultaneously and holding on to memory?

> The first patch replaces the -m flags for the gcc compiler with
> -f flags. Maybe you should do this in the source distribution.

Yeah.  The situation is that older gcc's (e.g. 2.96) reject -f, while
newer ones only warn about -m.  So the decision was made to stay with
-m for now because I build the rpms on a RedHat 7.1 machine for
maximum portability.  Maybe I will soon abandon the 7.x line and start
building on 8.x with gcc 3.2, in which case I will apply the patch.