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Re: second thoughts on using dl_iterate_phdr() for cache-validation


>>>>> On Thu, 4 Nov 2004 15:53:55 -0800, Roland McGrath <roland@redhat.com> said:

  Roland> No new ABI is going to go in very soon.  We have frozen the
  Roland> GLIBC_2.3.4 ABI already.

That's unfortunate.
Is there a mechanism to queue this patch so it doesn't get lost again
when 2.3.5 is opened up?

  Roland> unsigned long long int is not an atomic type on all
  Roland> platforms, so your code as written is not acceptable without
  Roland> adding locking for machines where it's not.

The incrementing is always done under protection of a lock.  The reading
is not, but on those machines where reading an "unsigned long long int"
isn't atomic, the effect is no worse than when using "unsigned int".
And on those machines where it is atomic, "unsigned long long int" pretty
much guarantees that the counter will never overflow.

Do you still think the patch is unacceptable in this regard?

  Roland> An interface to return the address of such variables is
  Roland> highly dubious, since it constrains the implementation and
  Roland> does so permanently for the future.

OK, I see your point.

Thanks,

	--david


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