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Re: GC changes
Fergus Henderson wrote:
> > If we have no automated way of testing it, people will break it all
> > the time.
>
> People break GCC all the time. GCC is always broken.
> What really matters is whether the bugs show up in practice.
> If the bugs show up in practice, then they can be tested for and fixed.
Bear in mind that GC bugs due to misoptimisation are _extremely_ rare
to trigger both at compile time and at run time, even compared with
normal optimisation bugs.
A GC must be triggered at exactly the wrong moment.
Therefore merely testing that code works at run time does not give the
same level of confidence as it does with normal optimisations.
You would need to trigger a GC at every possible instruction, and mark
all unreached objects such that later attempts to access them trap.
-- Jamie