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Re: What do IFUNC resolvers need to be useful?
- From: Szabolcs Nagy <szabolcs dot nagy at arm dot com>
- To: "Jose E. Marchesi" <jose dot marchesi at oracle dot com>, Carlos O'Donell <carlos at redhat dot com>
- Cc: GNU C Library <libc-alpha at sourceware dot org>, <nd at arm dot com>
- Date: Tue, 22 Mar 2016 16:09:46 +0000
- Subject: Re: What do IFUNC resolvers need to be useful?
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On 22/03/16 15:13, Jose E. Marchesi wrote:
>
> > Should IFUNC resolver get passed in a pointer to the
> > environment?
>
> I think that it would be a great improvement.
>
> One can imagine to use that on the libc for example to temporarily
> disable the optimized functions. That can be useful for debugging,
> but also in our testsuite to test the various versions of a
> function.
>
> +1
>
> Sometimes old code breaks with new optimized routines, such as
> multithread issues in routines using block-initialize instructions in
> sparc. In these situations it would be very useful to disable certain
> versions of the routines.
>
> Also, it would allow users to easily benchmark the performance of the
> routines applications/platforms and choose the best implementation for
> them.
>
so what should happen if a signal interrupts setenv
and the signal handler calls a function through plt
that needs ifunc resolution..