[llvm-dev] Need help with code generation

James Molloy via llvm-dev llvm-dev at lists.llvm.org
Tue Mar 22 05:03:08 PDT 2016


Rafael,

I appreciate that your goals are to create a performant linker, quickly. I
understand that and wouldn't want to slow you down unnecessarily,
especially as I appreciate that I'm on the sidelines and not producing
patches for LLD at the moment.

I also appreciate that LLD/ELF development has certainly picked up pace
recently and we might actually have a functioning linker sometime soon.
That is very exciting, and thankyou for all your work.

My worry is that the technical debt accrued will have to be paid off by
someone at some point. At some point, someone will have to come along and
make LLD robust ("enough", for some definition), and the current decision
will make that person's job much harder.

I'm not asking for horrendously defensive programming - hell, a simple
"FIXME" on every place where you deliberately dereference a
non-bounds-checked pointer would be sufficient! Re-discovering this sort of
thing is exponentially more difficult than taking a small amount of time
when originally writing the code.

Just an opinion.

Cheers,

James

On Tue, 22 Mar 2016 at 11:27 Rafael EspĂ­ndola <llvm-dev at lists.llvm.org>
wrote:

> > Maybe not, but it's not impossible either - browsers manage to harden
> themselves against malicious input and they operate in a far hostile
> environment with many more input formats than we do.
>
> It is important to note how different they are. Both Firefox and
> Chromium have people working just to try to make them more secure.
> Compare that with LLVM: One week ago I pointed out that your patch
> (r263521) introduces a crash. It still hasn't been reverted or even
> acknowledge yet.
>
>
> > I'm not trying to shift your personal goal, or to direct the features
> that you choose to put your time into, but I am interested in project
> policy.
>
> Why do you care about policy that is not followed? A policy saying
> llvm should not crash on any input is as relevant as one that says
> that clang should keep bootstrapping in under one second.
>
> So, if we stick to reality, what we have is that lld (ELF and COFF)
> are already the most reliable parts of the toolchain. If not for Rui
> and I being upfront about it most people would not even know that you
> could crash it. So please, just let us keep working on the most
> reliable part of the toolchain.
>
> Cheers,
> Rafael
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160322/d6f08ed3/attachment.html>


More information about the llvm-dev mailing list