public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct
@ 2006-05-21 9:20 fischer at td dot mw dot tum dot de
2006-05-21 9:31 ` [Bug c/27697] " fischer at td dot mw dot tum dot de
` (11 more replies)
0 siblings, 12 replies; 13+ messages in thread
From: fischer at td dot mw dot tum dot de @ 2006-05-21 9:20 UTC (permalink / raw)
To: gcc-bugs
In this snippet of code:
struct foo {
int x[2][10];
};
void f(void)
{
const struct foo bar;
const int (*baz)[10] = bar.x; /* should be ok */
int (*qoox)[10] = bar.x; /* should warn */
bar.x[0][1] = 23; /* error: asignment to const */
(*qoox)[1] = 23;
}
bar is const, so bar.x is (const int *), so an assignment to (const int *)
should be ok, while an assignment to (int *) violates the type constraints (all
according to 6.7.3 in the Standard).
in gcc 4.1.0, the behaviour is reversed: assignment to (int *) goes unnoticed
while assignment to (const int *) issues an "incompatible pointer" warning.
--
Summary: incorrect warning about constness of pointer to an array
in a const struct
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: fischer at td dot mw dot tum dot de
GCC build triplet: i586-suse-linux
GCC host triplet: i586-suse-linux
GCC target triplet: i586-suse-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
@ 2006-05-21 9:31 ` fischer at td dot mw dot tum dot de
2006-05-21 16:15 ` [Bug c/27697] [4.0/4.1/4.2 Regression] " pinskia at gcc dot gnu dot org
` (10 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: fischer at td dot mw dot tum dot de @ 2006-05-21 9:31 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from fischer at td dot mw dot tum dot de 2006-05-21 09:31 -------
In the function above:
bar.x[0][0] = 23; // gcc 4.1 gives error
*bar.x[0] = 23; // gcc 4.1 gives NO error
both lines do the same ....
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
2006-05-21 9:31 ` [Bug c/27697] " fischer at td dot mw dot tum dot de
@ 2006-05-21 16:15 ` pinskia at gcc dot gnu dot org
2006-05-21 23:17 ` neil at daikokuya dot co dot uk
` (9 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-05-21 16:15 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from pinskia at gcc dot gnu dot org 2006-05-21 16:15 -------
This is also rejects valid with -pedantic-errors.
I don't understand what is correct here so I am not going to confirm it.
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |diagnostic, rejects-valid
Known to fail| |4.0.3 4.1.0 4.2.0
Known to work| |4.0.2
Summary|incorrect warning about |[4.0/4.1/4.2 Regression]
|constness of pointer to an |incorrect warning about
|array in a const struct |constness of pointer to an
| |array in a const struct
Target Milestone|--- |4.0.4
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
2006-05-21 9:31 ` [Bug c/27697] " fischer at td dot mw dot tum dot de
2006-05-21 16:15 ` [Bug c/27697] [4.0/4.1/4.2 Regression] " pinskia at gcc dot gnu dot org
@ 2006-05-21 23:17 ` neil at daikokuya dot co dot uk
2006-05-21 23:53 ` jsm28 at gcc dot gnu dot org
` (8 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: neil at daikokuya dot co dot uk @ 2006-05-21 23:17 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from neil at daikokuya dot co dot uk 2006-05-21 23:17 -------
Subject: Re: [4.0/4.1/4.2 Regression] incorrect warning about constness of
pointer to an array in a const struct
pinskia at gcc dot gnu dot org wrote:-
>
>
> ------- Comment #2 from pinskia at gcc dot gnu dot org 2006-05-21 16:15 -------
> This is also rejects valid with -pedantic-errors.
> I don't understand what is correct here so I am not going to confirm it.
If I understand correctly I think the report is correct about
validity for both C90 and C99; another front end gives
"/tmp/bar.c", line 10: error: cannot convert initializer of type "const
int (*)[10]" to type "int (*)[10]"
int (*qoox)[10] = bar.x; /* should warn */
^
"/tmp/bar.c", line 11: error: expression must be a modifiable lvalue
bar.x[0][1] = 23; /* error: asignment to const */
^
"/tmp/bar.c", line 9: warning: variable "baz" declared but not used
const int (*baz)[10] = bar.x; /* should be ok */
^
2 errors found compiling "/tmp/bar.c".
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (2 preceding siblings ...)
2006-05-21 23:17 ` neil at daikokuya dot co dot uk
@ 2006-05-21 23:53 ` jsm28 at gcc dot gnu dot org
2006-06-04 19:20 ` mmitchel at gcc dot gnu dot org
` (7 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2006-05-21 23:53 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from jsm28 at gcc dot gnu dot org 2006-05-21 23:53 -------
Confirmed, my first guess as to a fix would be to make build_component_ref
arrange for the type of the COMPONENT_REF to have the necessary qualifiers via
c_build_qualified_type.
--
jsm28 at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
OtherBugsDependingO| |16620, 16989
nThis| |
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2006-05-21 23:53:40
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (3 preceding siblings ...)
2006-05-21 23:53 ` jsm28 at gcc dot gnu dot org
@ 2006-06-04 19:20 ` mmitchel at gcc dot gnu dot org
2006-07-17 3:42 ` mmitchel at gcc dot gnu dot org
` (6 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: mmitchel at gcc dot gnu dot org @ 2006-06-04 19:20 UTC (permalink / raw)
To: gcc-bugs
--
mmitchel at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Priority|P3 |P1
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (4 preceding siblings ...)
2006-06-04 19:20 ` mmitchel at gcc dot gnu dot org
@ 2006-07-17 3:42 ` mmitchel at gcc dot gnu dot org
2006-08-16 17:18 ` jsm28 at gcc dot gnu dot org
` (5 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: mmitchel at gcc dot gnu dot org @ 2006-07-17 3:42 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from mmitchel at gcc dot gnu dot org 2006-07-17 03:42 -------
The trick of using -pedantic-errors to turn every invalid warning into
rejects-valid is not useful. Downgrading to P2.
--
mmitchel at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords|rejects-valid |
Priority|P1 |P2
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (5 preceding siblings ...)
2006-07-17 3:42 ` mmitchel at gcc dot gnu dot org
@ 2006-08-16 17:18 ` jsm28 at gcc dot gnu dot org
2006-08-16 23:11 ` jsm28 at gcc dot gnu dot org
` (4 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2006-08-16 17:18 UTC (permalink / raw)
To: gcc-bugs
------- Comment #6 from jsm28 at gcc dot gnu dot org 2006-08-16 17:17 -------
Testing a patch.
--
jsm28 at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |jsm28 at gcc dot gnu dot org
|dot org |
Status|NEW |ASSIGNED
Last reconfirmed|2006-05-21 23:53:40 |2006-08-16 17:17:52
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (6 preceding siblings ...)
2006-08-16 17:18 ` jsm28 at gcc dot gnu dot org
@ 2006-08-16 23:11 ` jsm28 at gcc dot gnu dot org
2006-08-16 23:12 ` jsm28 at gcc dot gnu dot org
` (3 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2006-08-16 23:11 UTC (permalink / raw)
To: gcc-bugs
------- Comment #7 from jsm28 at gcc dot gnu dot org 2006-08-16 23:10 -------
Subject: Bug 27697
Author: jsm28
Date: Wed Aug 16 23:10:46 2006
New Revision: 116194
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=116194
Log:
PR c/27697
* c-typeck.c (build_component_ref): Combine qualifiers of
structure or union and field.
testsuite:
* gcc.dg/qual-component-1.c: New test.
Added:
trunk/gcc/testsuite/gcc.dg/qual-component-1.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/c-typeck.c
trunk/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0/4.1/4.2 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (7 preceding siblings ...)
2006-08-16 23:11 ` jsm28 at gcc dot gnu dot org
@ 2006-08-16 23:12 ` jsm28 at gcc dot gnu dot org
2006-08-17 13:02 ` [Bug c/27697] [4.0 " brett dot albertson at stratech dot com
` (2 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2006-08-16 23:12 UTC (permalink / raw)
To: gcc-bugs
------- Comment #8 from jsm28 at gcc dot gnu dot org 2006-08-16 23:12 -------
Subject: Bug 27697
Author: jsm28
Date: Wed Aug 16 23:12:37 2006
New Revision: 116195
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=116195
Log:
PR c/27697
* c-typeck.c (build_component_ref): Combine qualifiers of
structure or union and field.
testsuite:
* gcc.dg/qual-component-1.c: New test.
Added:
branches/gcc-4_1-branch/gcc/testsuite/gcc.dg/qual-component-1.c
- copied unchanged from r116194,
trunk/gcc/testsuite/gcc.dg/qual-component-1.c
Modified:
branches/gcc-4_1-branch/gcc/ChangeLog
branches/gcc-4_1-branch/gcc/c-typeck.c
branches/gcc-4_1-branch/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (8 preceding siblings ...)
2006-08-16 23:12 ` jsm28 at gcc dot gnu dot org
@ 2006-08-17 13:02 ` brett dot albertson at stratech dot com
2006-08-26 0:11 ` jsm28 at gcc dot gnu dot org
2007-02-03 17:18 ` gdr at gcc dot gnu dot org
11 siblings, 0 replies; 13+ messages in thread
From: brett dot albertson at stratech dot com @ 2006-08-17 13:02 UTC (permalink / raw)
To: gcc-bugs
------- Comment #9 from brett dot albertson at stratech dot com 2006-08-17 13:02 -------
(In reply to comment #7)
> Subject: Bug 27697
This fails on i386-pc-solaris2.10 on trunk with:
Executing on host: /u01/var/tmp/gcc_trunk_svn/gcc_20060817/gcc/xgcc
-B/u01/var/tmp/gcc_trunk_svn/gcc_20060817/gcc/
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c
-fno-show-column -S -o qual-component-1.s (timeout = 300)
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c: In
function 'f':^M
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c:45:
error: assignment of read-only member 'd'^M
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c:46:
error: assignment of read-only location^M
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c:47:
error: assignment of read-only location^M
etc.
and
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c: In
function 'g':^M
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c:113:
warning: initialization from in compatible pointer type^M
/u01/var/tmp/gcc_trunk_svn/gcc/gcc/testsuite/gcc.dg/qual-component-1.c:118:
warning: assignment from incompatible pointer type^M
etc.
Brett
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (9 preceding siblings ...)
2006-08-17 13:02 ` [Bug c/27697] [4.0 " brett dot albertson at stratech dot com
@ 2006-08-26 0:11 ` jsm28 at gcc dot gnu dot org
2007-02-03 17:18 ` gdr at gcc dot gnu dot org
11 siblings, 0 replies; 13+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2006-08-26 0:11 UTC (permalink / raw)
To: gcc-bugs
------- Comment #10 from jsm28 at gcc dot gnu dot org 2006-08-26 00:11 -------
Not working on 4.0 fix, as noted at
http://gcc.gnu.org/ml/gcc-patches/2006-08/msg00566.html one test fails there
with the patch applied.
--
jsm28 at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|jsm28 at gcc dot gnu dot org|unassigned at gcc dot gnu
| |dot org
Status|ASSIGNED |NEW
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
* [Bug c/27697] [4.0 Regression] incorrect warning about constness of pointer to an array in a const struct
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
` (10 preceding siblings ...)
2006-08-26 0:11 ` jsm28 at gcc dot gnu dot org
@ 2007-02-03 17:18 ` gdr at gcc dot gnu dot org
11 siblings, 0 replies; 13+ messages in thread
From: gdr at gcc dot gnu dot org @ 2007-02-03 17:18 UTC (permalink / raw)
To: gcc-bugs
------- Comment #11 from gdr at gcc dot gnu dot org 2007-02-03 17:18 -------
Fixed in GCC-4.1.2.
--
gdr at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution| |FIXED
Target Milestone|4.0.4 |4.1.2
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27697
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2007-02-03 17:18 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2006-05-21 9:20 [Bug c/27697] New: incorrect warning about constness of pointer to an array in a const struct fischer at td dot mw dot tum dot de
2006-05-21 9:31 ` [Bug c/27697] " fischer at td dot mw dot tum dot de
2006-05-21 16:15 ` [Bug c/27697] [4.0/4.1/4.2 Regression] " pinskia at gcc dot gnu dot org
2006-05-21 23:17 ` neil at daikokuya dot co dot uk
2006-05-21 23:53 ` jsm28 at gcc dot gnu dot org
2006-06-04 19:20 ` mmitchel at gcc dot gnu dot org
2006-07-17 3:42 ` mmitchel at gcc dot gnu dot org
2006-08-16 17:18 ` jsm28 at gcc dot gnu dot org
2006-08-16 23:11 ` jsm28 at gcc dot gnu dot org
2006-08-16 23:12 ` jsm28 at gcc dot gnu dot org
2006-08-17 13:02 ` [Bug c/27697] [4.0 " brett dot albertson at stratech dot com
2006-08-26 0:11 ` jsm28 at gcc dot gnu dot org
2007-02-03 17:18 ` gdr at gcc dot gnu dot org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).