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From: "fweimer at redhat dot com" <sourceware-bugzilla@sourceware.org>
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Subject: [Bug dynamic-link/28745] _dl_find_object miscompilation on powerpc64le
Date: Tue, 04 Jan 2022 12:11:14 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D28745

--- Comment #2 from Florian Weimer <fweimer at redhat dot com> ---
The acquire load doesn't have a memory clobber:

static inline uint64_t
__atomic_wide_counter_load_acquire (__atomic_wide_counter *c)
{
  return ({ __typeof (*(&c->__value64)) __atg101_val =3D ({ __typeof ((__ty=
peof
(*(&c->__value64))) *(&c->__value64)) __atg100_val; __asm ("" : "=3Dr"
(__atg100_val) : "0" (*(&c->__value64))); __atg100_val; }); __asm ("lwsync"=
 :::
"memory"); __atg101_val; });
}

So it's unordered with regards to the defensive copy. No GCC bug.

--=20
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