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* [Bug c/50154] New: attribute printf and scanf should imply attribute nonnull
@ 2011-08-22 16:29 bruno at clisp dot org
2011-08-22 16:35 ` [Bug c/50154] " bruno at clisp dot org
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: bruno at clisp dot org @ 2011-08-22 16:29 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50154
Bug #: 50154
Summary: attribute printf and scanf should imply attribute
nonnull
Classification: Unclassified
Product: gcc
Version: 4.6.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: bruno@clisp.org
Created attachment 25076
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25076
test case
When a function is declared as taking a printf or scanf format string, gcc
gives a warning when a format string with invalid syntax is passed. It should
also give a warning when a NULL format string is passed.
How to reproduce:
Save the test case file as foo.c.
$ gcc -Wformat=2 -c foo.c
[no warning]
$ gcc -Wformat=2 -c foo.c -DDECLARE_NONNULL
foo.c: In function 'foo':
foo.c:10:3: warning: null argument where non-null required (argument 3)
[-Wnonnull]
Rationale:
1) ISO C 99 specifies that the printf and scanf format strings must be
"multibyte
character sequences"; that excludes NULL.
See ISO C 99 sections 7.19.6.1 paragraph 3 and 7.19.6.2 paragraph 3.
2) Passing NULL as first argument to printf crashes the program on FreeBSD,
Solaris, and other platforms.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/50154] attribute printf and scanf should imply attribute nonnull
2011-08-22 16:29 [Bug c/50154] New: attribute printf and scanf should imply attribute nonnull bruno at clisp dot org
@ 2011-08-22 16:35 ` bruno at clisp dot org
2011-08-24 21:17 ` pinskia at gcc dot gnu.org
2011-08-25 11:54 ` jakub at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: bruno at clisp dot org @ 2011-08-22 16:35 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50154
bruno at clisp dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #25076|0 |1
is obsolete| |
--- Comment #1 from bruno at clisp dot org 2011-08-22 16:29:26 UTC ---
Created attachment 25077
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25077
test case (corrected)
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/50154] attribute printf and scanf should imply attribute nonnull
2011-08-22 16:29 [Bug c/50154] New: attribute printf and scanf should imply attribute nonnull bruno at clisp dot org
2011-08-22 16:35 ` [Bug c/50154] " bruno at clisp dot org
@ 2011-08-24 21:17 ` pinskia at gcc dot gnu.org
2011-08-25 11:54 ` jakub at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2011-08-24 21:17 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50154
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |diagnostic
Severity|normal |enhancement
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-08-24 21:15:37 UTC ---
I think it is better if the person adds nonnull attribute themselves rather
than GCC adding it with the printf format.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/50154] attribute printf and scanf should imply attribute nonnull
2011-08-22 16:29 [Bug c/50154] New: attribute printf and scanf should imply attribute nonnull bruno at clisp dot org
2011-08-22 16:35 ` [Bug c/50154] " bruno at clisp dot org
2011-08-24 21:17 ` pinskia at gcc dot gnu.org
@ 2011-08-25 11:54 ` jakub at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: jakub at gcc dot gnu.org @ 2011-08-25 11:54 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50154
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
CC| |jakub at gcc dot gnu.org
Resolution| |INVALID
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-08-25 11:13:59 UTC ---
Yeah, I agree with that.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-08-25 11:14 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2011-08-22 16:29 [Bug c/50154] New: attribute printf and scanf should imply attribute nonnull bruno at clisp dot org
2011-08-22 16:35 ` [Bug c/50154] " bruno at clisp dot org
2011-08-24 21:17 ` pinskia at gcc dot gnu.org
2011-08-25 11:54 ` jakub at gcc dot gnu.org
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