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* optimization/8632: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
@ 2002-11-25 8:48 glen
0 siblings, 0 replies; 3+ messages in thread
From: glen @ 2002-11-25 8:48 UTC (permalink / raw)
To: gcc-gnats
>Number: 8632
>Category: optimization
>Synopsis: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: wrong-code
>Submitter-Id: net
>Arrival-Date: Mon Nov 18 19:26:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator: Glen Nakamura
>Release: gcc version 3.3 20021118 (experimental)
>Organization:
>Environment:
i686-pc-linux-gnu
>Description:
GCC generates the following code for function main:
main:
pushl %ebp
movl %esp, %ebp
pushl %edi
pushl %esi
xorl %esi, %esi
pushl %ebx
subl $12, %esp
andl $-16, %esp
.p2align 4,,15
.L8:
movl %esi, 4(%esp)
movl a, %eax
movl %eax, (%esp)
call foo
testl %eax, %eax
je .L14
decl %eax
leal 1(%esi), %ebx
je .L15
.L11:
movl %ebx, %esi
jmp .L8
.p2align 4,,7
.L15:
movl %ebx, 4(%esp)
movl %edi, (%esp) <<< %edi is uninitialized
call foo
...
The problem goes away if foo calls another function,
or if foo writes to a global variable. The testcase also
works if we compile with any of the following:
gcc -O0 -mcpu=i686 testcase.c
gcc -O1 -mcpu=i686 testcase.c
gcc -O2 -mcpu=i586 testcase.c
>How-To-Repeat:
gcc -O2 -mcpu=i686 testcase.c
./a.out
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
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Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="testcase.c"
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: optimization/8632: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
@ 2003-02-18 14:07 ebotcazou
0 siblings, 0 replies; 3+ messages in thread
From: ebotcazou @ 2003-02-18 14:07 UTC (permalink / raw)
To: gcc-bugs, gcc-prs, glen, nobody
Synopsis: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
State-Changed-From-To: open->closed
State-Changed-By: ebotcazou
State-Changed-When: Tue Feb 18 14:07:01 2003
State-Changed-Why:
Fixed, very likely by Jan's patch.
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8632
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: optimization/8632: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
@ 2002-12-02 18:06 Glen Nakamura
0 siblings, 0 replies; 3+ messages in thread
From: Glen Nakamura @ 2002-12-02 18:06 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR optimization/8632; it has been noted by GNATS.
From: Glen Nakamura <glen@imodulo.com>
To: gcc-gnats@gcc.gnu.org, gcc-bugs@gcc.gnu.org
Cc:
Subject: Re: optimization/8632: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects
Date: Mon, 2 Dec 2002 16:01:25 -1000
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8632
This patch by Jan Hubicka fixes the problem on i686-pc-linux-gnu:
http://gcc.gnu.org/ml/gcc-patches/2002-12/msg00136.html
- glen
^ permalink raw reply [flat|nested] 3+ messages in thread
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2002-11-25 8:48 optimization/8632: [3.3 regression] uninitialized argument passed to leaf function w/o side-effects glen
2002-12-02 18:06 Glen Nakamura
2003-02-18 14:07 ebotcazou
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