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From: "jakub at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug debug/43516] [4.5 Regression] "-fcompare-debug failure" at -O2
Date: Fri, 26 Mar 2010 10:42:00 -0000	[thread overview]
Message-ID: <20100326104202.21231.qmail@sourceware.org> (raw)
In-Reply-To: <bug-43516-14164@http.gcc.gnu.org/bugzilla/>



------- Comment #10 from jakub at gcc dot gnu dot org  2010-03-26 10:42 -------
In particular, for -g0 the alias set of that unsigned 1 bit type actually
changes.
This is on the #c1 testcase, with
-g -fcompare-debug=-gtoggle pr43516.c -O2 -fdump-final-insns=/tmp/1
resp.
-g0 -fcompare-debug=-gtoggle pr43516.c -O2 -fdump-final-insns=/tmp/2
Putting a breakpoint on new_alias_set when it returns 41 or more, when it
returns 41 in the backtrace is first get_alias_set for the signed 1 bit type
that c_common_signed_type returned, then 2 frames up get_alias_set for the
problematic unsigned 1 bit type.  In -g0 case a few get_alias_set calls on this
unsigned 1 bit type suddenly c_common_signed_type returns a different type,
which doesn't have alias set computed, while for -g it doesn't.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43516


  parent reply	other threads:[~2010-03-26 10:42 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-25 11:27 [Bug debug/43516] New: " zsojka at seznam dot cz
2010-03-25 11:31 ` [Bug debug/43516] " zsojka at seznam dot cz
2010-03-25 11:32 ` zsojka at seznam dot cz
2010-03-25 16:03 ` jakub at gcc dot gnu dot org
2010-03-25 16:04 ` [Bug debug/43516] [4.5 Regression] " pinskia at gcc dot gnu dot org
2010-03-25 16:49 ` [Bug debug/43516] " jakub at gcc dot gnu dot org
2010-03-25 16:51 ` [Bug debug/43516] [4.5 Regression] " jakub at gcc dot gnu dot org
2010-03-25 17:14 ` zsojka at seznam dot cz
2010-03-25 18:34 ` pinskia at gcc dot gnu dot org
2010-03-25 21:06 ` jakub at gcc dot gnu dot org
2010-03-26 10:28 ` jakub at gcc dot gnu dot org
2010-03-26 10:42 ` jakub at gcc dot gnu dot org [this message]
2010-03-26 11:03 ` jakub at gcc dot gnu dot org
2010-03-26 11:51 ` rguenth at gcc dot gnu dot org
2010-03-26 13:14 ` jakub at gcc dot gnu dot org
2010-03-26 13:15 ` jakub at gcc dot gnu dot org
2010-03-26 13:33 ` rguenth at gcc dot gnu dot org
2010-03-26 13:36 ` rguenth at gcc dot gnu dot org
2010-03-26 16:19 ` jakub at gcc dot gnu dot org
2010-03-27 21:39 ` jakub at gcc dot gnu dot org
2010-04-07 14:24 ` jakub at gcc dot gnu dot org

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