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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/94444] __attribute__((access(...))) ignored for memcpy when
 compiling with -Os
Date: Wed, 01 Apr 2020 19:46:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94444

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |WONTFIX
           Keywords|                            |diagnostic

--- Comment #5 from Martin Sebor <msebor at gcc dot gnu.org> ---
Attribute access has an effect only on calls present in the IL after all
optimizations have run.  In the test case, because the local variable isn't
used after the copy, the call is removed and there is no warning.  (The war=
ning
comes back if the buffer is used or made extern or static.)  This is by des=
ign,
and expected not just of the attribute but of most late warnings (including,
for example, -Warray-bounds).  Doing otherwise and processing the attribute
much earlier would lead to warnings for unreachable code that most users vi=
ew
as false positives.  We have no plans to change it.=