From: Ian Lance Taylor <iant@google.com>
To: "Paulo J. Matos" <paulo@matos-sorge.com>
Cc: gcc@gcc.gnu.org
Subject: Re: Volatile qualification on pointer and data
Date: Tue, 20 Sep 2011 16:36:00 -0000 [thread overview]
Message-ID: <mcrr53bcgte.fsf@coign.corp.google.com> (raw)
In-Reply-To: <j5adnq$bb4$1@dough.gmane.org> (Paulo J. Matos's message of "Tue, 20 Sep 2011 17:07:21 +0100")
"Paulo J. Matos" <paulo@matos-sorge.com> writes:
> The following code:
> static const unsigned int foo = 1;
> unsigned int test( void )
> {
> const volatile unsigned int *bar = &foo;
> return ( *bar );
> }
>
> in GCC45 works as expected:
> $test:
> ld AL,#foo ;; AL is return register
> bra 0,X ;; end function
>
> in GCC46:
> $test:
> ld AL,0
> bra 0,X
>
> This is worrying because qualifying the data as volatile should be
> enough to prevent these sort of optimizations. It did until GCC46.
I agree that this looks like a bug. Please file a bug report marked as
a regression.
Ian
next prev parent reply other threads:[~2011-09-20 16:36 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-20 16:08 Paulo J. Matos
2011-09-20 16:36 ` Ian Lance Taylor [this message]
2011-09-21 7:07 ` David Brown
2011-09-21 8:22 ` Paulo J. Matos
2011-09-21 10:20 ` David Brown
2011-09-21 13:57 ` Ian Lance Taylor
2011-09-21 14:25 ` David Brown
2011-09-21 14:57 ` Paulo J. Matos
2011-09-22 8:39 ` David Brown
2011-09-22 21:15 ` Richard Guenther
2011-09-23 11:33 ` Paulo J. Matos
2011-09-23 11:51 ` Paulo J. Matos
2011-09-23 13:17 ` Paulo J. Matos
2011-09-21 18:51 ` Georg-Johann Lay
2011-09-22 8:53 ` David Brown
2011-09-24 15:10 ` John Regehr
2011-09-24 15:49 ` David Brown
2011-09-24 16:26 ` David Brown
2011-09-24 19:38 ` John Regehr
2011-09-25 13:03 ` David Brown
2011-09-25 15:15 ` Andreas Schwab
2011-09-25 16:33 ` David Brown
2011-09-25 16:36 ` David Brown
2011-09-25 16:06 ` Dave Korn
2011-09-25 22:05 ` David Brown
2011-09-25 22:05 ` David Brown
2011-09-26 7:14 ` Miles Bader
2011-09-26 8:53 ` David Brown
2011-09-26 8:58 ` David Brown
2011-09-21 8:14 ` Paulo J. Matos
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