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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/102608] [12 regression] Recent change to VN causes bogus Wuninitialized warnings & kernel build failures
Date: Wed, 06 Oct 2021 08:39:21 +0000	[thread overview]
Message-ID: <bug-102608-4-fLRTVOroDc@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-102608-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102608

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|11.0                        |12.0
   Last reconfirmed|                            |2021-10-06
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
>    old32_34 = .DEFERRED_INIT (4, 2, 0);
> 
> ...
> 
> -  _24 = .DEFERRED_INIT (4, 2, 0);
> -  __res ={v} _24;
> +  __res ={v} old32_34;
> 
> 
> # 68 "../arch/mips/include/asm/cmpxchg.h"
> This is due to __typeof(*((volatile u32 *)ptr)) __ret
> 
> 
> 
> The warning is kinda of correct but wrong as it uses the wrong decl :).
> 
> Fre maybe should be disabled for DEFERRED_INIT ....

Hmm, I did consider that but then I thought it wouldn't matter (there were no
testsuite FAILs).

But sure, I can easily make .DEFERRED_INIT always produce a VARYING value.

  parent reply	other threads:[~2021-10-06  8:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-05 14:51 [Bug tree-optimization/102608] New: " law at gcc dot gnu.org
2021-10-05 15:37 ` [Bug tree-optimization/102608] " pinskia at gcc dot gnu.org
2021-10-05 15:38 ` pinskia at gcc dot gnu.org
2021-10-06  8:39 ` rguenth at gcc dot gnu.org [this message]
2021-10-07 12:28 ` cvs-commit at gcc dot gnu.org
2021-10-07 12:29 ` rguenth at gcc dot gnu.org

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