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From: "rth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/65913] Linking failure without -latomic
Date: Tue, 28 Apr 2015 16:01:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65913

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |rth at gcc dot gnu.org

--- Comment #2 from Richard Henderson <rth at gcc dot gnu.org> ---
Created attachment 35416
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35416&action=edit
proposed patch

jwakely suggested on irc reverting the -alignment fake pointer
for the integral type template.  

Note that there are weird targets that have non-power-of-two
integral types:

config/avr/avr-modes.def:FRACTIONAL_INT_MODE (PSI, 24, 3);

Thankfully, avr doesn't also have atomic operations on this type,
so the second part of fold_builtin_atomic_always_lock_free would fail.

But I think we can also do better for non-integral types, so it's
probably better to attack this inside the compiler.