Re: Do we still need ggc-simple

[Nick Burrett <nick at dsvr dot net>]

Steven Bosscher wrote:
> On Wednesday 10 December 2003 11:41, Nick Burrett wrote:
>
> > Steven Bosscher wrote:
> >
> > > Why do we still have ggc-simple?  Are there any targets for which
> > > ggc-page doesn't work?
> >
> > Yes (arm-riscos-aof), though it is maintained outside of the GCC tree.
>
>
> OK.  So I like bitching.
>
> Why is arm-riscos-aof not using ggc-page with malloc?

Sorry.  The last time I looked to make the decision on using ggc-page or 
ggc-simple, I figured that ggc-page was a solely mmap implementation. 
Upon reading the code further, I notice it isn't and therefore I will 
drop my requirement for ggc-simple.

> I know for sure since building GCC with ggc-simple.c has been impossible since 
> at least 26 Oct 2003.  On that day the zone collector was commited, and 
> anyone who has tried to build gcc with ggc-simple as the collector should 
> have seen a link failure because tree_zone is not declared anywhere.  I've 
> heard no complaint, and my conclusion has to be that in almost two months 
> time, nobody has noticed that ggc-simple.c is currently broken.

You are making the assumption that all port maintainers keep their ports 
right up-to-date.  Due to limited resources and the work required, it 
has taken me and a small team of developers over a year to move from 
2.95 to a 3.3 port.  Part of this is due to having to write/maintain a C 
library, an assembler, a linker, a library maker and the ports of 
several other applications.  The other part of the problem is not having 
that much time out of office-hours to work on such stuff.

I would have come across the breakage to ggc-simple.c in about 12 months 
from now, at which point I'd do the necessary work to swap to ggc-page.c 
(if there was any to be done).

> Having three collectors like we do now is very unpleasant.  Every time someone 
> tries to add a feature to the GC system, it has to be added to _three_ 
> collectors.  Bah.  Especially since ggc-simple is almost unused.  I would 
> very much like to see it go away.

I don't disagree.  If you're committing a patch that breaks an interface 
(in this case ggc-simple.c), then either you should have fixed your 
patch to fix the interface, or simply removed ggc-simple.c.

Breaking the ggc-simple.c or removing the file entirely has the same net 
effect -- it isn't going to work in either case.  Then if somebody 
complains, you could either revert it's removal and fix the breakages, 
or help the maintainer to understand why ggc-page.c should be used instead.

Regards,


Nick.