PATCH: Make STT_GNU_IFUNC symbol dynamic

Petr Baudis pasky@suse.cz
Sun May 24 21:20:00 GMT 2009


  Hi!

On Sat, May 23, 2009 at 02:44:02PM -0700, Ulrich Drepper wrote:
> The reason we need such a relocation is that we have no symbol at
> runtime.  We cannot use a normal PLT slot relocation since this would
> perform a global name lookup, which is wrong.

  Why did you actually choose IFUNC to return just a pointer instead of
symbol name? That would make it possible to do the resolving step once
during e.g. ldconfig and then cache it system-wide, instead of having
the useless overhead of re-resolving it each time a program is called.
(I have also heard that this overhead can be quite significant on ppc.)

-- 
				Petr "Pasky" Baudis
The lyf so short, the craft so long to lerne. -- Chaucer



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