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* [Bug c++/40111] New: "for" loop wrong code generation
@ 2009-05-12 9:36 face dot mitev at gmail dot com
2009-05-12 9:51 ` [Bug c++/40111] " rguenth at gcc dot gnu dot org
2009-05-12 9:54 ` face dot mitev at gmail dot com
0 siblings, 2 replies; 3+ messages in thread
From: face dot mitev at gmail dot com @ 2009-05-12 9:36 UTC (permalink / raw)
To: gcc-bugs
This for loop
for(unsigned i=object::min(_digits, (int)NATIVE_DIGITS);i<NATIVE_DIGITS;++i)
inside_digit[i]=0;
generates the following incorrect code.
.L182:
.loc 12 59 0
movl -8(%rbp), %eax
movq -24(%rbp), %rdx
mov %eax, %eax
movq $0, (%rdx,%rax,8)
.loc 12 58 0
addl $1, -8(%rbp)
.L181:
cmpl $3, -8(%rbp)
jbe .L182
jmp .L183
This code always runs the body at least once, which, I think is incorrect.
I'm sorry I cannot include a simple test case to reproduce it, but it is very
hard to trigger and trying to isolate it just makes it go away.
--
Summary: "for" loop wrong code generation
Product: gcc
Version: 4.3.2
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: face dot mitev at gmail dot com
GCC build triplet: x86_64 linux gnu
GCC host triplet: x86_64 linux gnu
GCC target triplet: x86_64 linux gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40111
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug c++/40111] "for" loop wrong code generation
2009-05-12 9:36 [Bug c++/40111] New: "for" loop wrong code generation face dot mitev at gmail dot com
@ 2009-05-12 9:51 ` rguenth at gcc dot gnu dot org
2009-05-12 9:54 ` face dot mitev at gmail dot com
1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-05-12 9:51 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from rguenth at gcc dot gnu dot org 2009-05-12 09:51 -------
We need a testcase that is reproducible.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |WAITING
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40111
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug c++/40111] "for" loop wrong code generation
2009-05-12 9:36 [Bug c++/40111] New: "for" loop wrong code generation face dot mitev at gmail dot com
2009-05-12 9:51 ` [Bug c++/40111] " rguenth at gcc dot gnu dot org
@ 2009-05-12 9:54 ` face dot mitev at gmail dot com
1 sibling, 0 replies; 3+ messages in thread
From: face dot mitev at gmail dot com @ 2009-05-12 9:54 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from face dot mitev at gmail dot com 2009-05-12 09:54 -------
Not a gcc bug, sorry for the confusion.
--
face dot mitev at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Resolution| |INVALID
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40111
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2009-05-12 9:54 UTC | newest]
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2009-05-12 9:36 [Bug c++/40111] New: "for" loop wrong code generation face dot mitev at gmail dot com
2009-05-12 9:51 ` [Bug c++/40111] " rguenth at gcc dot gnu dot org
2009-05-12 9:54 ` face dot mitev at gmail dot com
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