Re: [commit 7.8] [patch+7.8] Fix 7.8 regression: resolve_dynamic_struct: Assertion `TYPE_NFIELDS (type) > 0' (PR 17642)

["H.J. Lu" <hjl.tools@gmail.com>]

On Mon, Dec 15, 2014 at 12:41 PM, Joel Brobecker <brobecker@adacore.com> wrote:
>> > This is a fairly big patch...
>> >   1. How bad is performance without it?
>>
>> It was very bad, like > 100x slower.
>
> OK, but 100x slower than 1usec is still unnoticeable. When did you start
> noticing it, for what kind of program (size?), and what type of delay
> were you seeing? Also, is that a regression compared to 7.7?  The idea
> is that, if it's just a second or two, or even ten, that's still quite
> bearable, and unless you are absolutely sure that your patch is safe,
> perhaps we should pass...
>
>> >   2. Can you find a binutils maintainer that will vouch that
>> >      this patch is 100% safe?
>>
>> As the x86 binutils maintainer, do I count?
>
> Absolutely. I just need someone who knows the code well enough to
> be trusted with its maintainance to stand behind the code and
> confirm that it is considered safe. In this case, I need extra safe,
> considering the fact that this is a .2 release.
>
> I hope I've described my concerns well enough for you to make
> the decision. Now that I have explained my thought process, I feel
> you're more qualified to make an informed decision now. Your call.
>
> Please remember that, if you do push it to 7.8, you'll need a PR
> associated to is so you can document the fix in the release wiki
> page (see fixes in GDB 7.8.2):
> https://sourceware.org/gdb/wiki/GDB_7.8_Release

The bug was filed against bintuils:

https://sourceware.org/bugzilla/show_bug.cgi?id=17677

since the code in question is in bfd.  But the actual bug is for GDB:

https://bugs.launchpad.net/ubuntu/+source/gdb/+bug/1388999

where the issues was observed.  I will retest by my patch and
backport it to 7.8 branch.

Thanks.


-- 
H.J.