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* [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS
@ 2007-07-23 17:28 ian at airs dot com
2007-07-26 21:33 ` [Bug preprocessor/32868] " tromey at gcc dot gnu dot org
` (5 more replies)
0 siblings, 6 replies; 7+ messages in thread
From: ian at airs dot com @ 2007-07-23 17:28 UTC (permalink / raw)
To: gcc-bugs
Compiling this C or C++ file:
#define __STDC_FORMAT_MACROS 1
#define __STDC_FORMAT_MACROS 1
produces these warnings:
foo.c:2:1: warning: "__STDC_FORMAT_MACROS" redefined
foo.c:1:1: warning: this is the location of the previous definition
This is because of these lines in libcpp/macro.c:
if (! ustrncmp (NODE_NAME (node), DSC ("__STDC_")))
node->flags |= NODE_WARN;
The idea behind these lines is sound: the compiler defines macros whose name
begins with "__STDC_". The user should not redefine them.
However, __STDC_FORMAT_MACROS is an exception here. This macro is not defined
by the compiler. It is intended to be defined by the user when compiling a C++
file to direct the <stdint.h> header file to define macros PRId32 and friends.
See footnote 182 in section 7.8.1 in C99.
If the user defines the macro in a .h file, as is permitted, then including
that some .h file twice, if it does not have an include guard, will give an
inappropriate warning. In particular this can happen with an autoconf-style
config.h file, as autoconf does not generate include guards for such files.
I expect that the right fix is to specifically exclude __STDC_FORMAT_MACROS
from this warning. Or perhaps another approach would be to specially mark the
macros defined in cpp_init_builtins.
--
Summary: Don't warn about redefinitions of __STDC_FORMAT_MACROS
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: preprocessor
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: ian at airs dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
@ 2007-07-26 21:33 ` tromey at gcc dot gnu dot org
2007-11-27 20:53 ` tromey at gcc dot gnu dot org
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2007-07-26 21:33 UTC (permalink / raw)
To: gcc-bugs
--
tromey at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at gcc dot gnu dot
| |org
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2007-07-26 21:33:20
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
2007-07-26 21:33 ` [Bug preprocessor/32868] " tromey at gcc dot gnu dot org
@ 2007-11-27 20:53 ` tromey at gcc dot gnu dot org
2007-11-28 14:29 ` ian at airs dot com
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2007-11-27 20:53 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from tromey at gcc dot gnu dot org 2007-11-27 20:53 -------
I think your proposed fix sounds ok.
I don't have a copy of the C++ standard handy.
Does this bug apply to both C and C++, or only C?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
2007-07-26 21:33 ` [Bug preprocessor/32868] " tromey at gcc dot gnu dot org
2007-11-27 20:53 ` tromey at gcc dot gnu dot org
@ 2007-11-28 14:29 ` ian at airs dot com
2007-11-28 16:26 ` tromey at gcc dot gnu dot org
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: ian at airs dot com @ 2007-11-28 14:29 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from ian at airs dot com 2007-11-28 14:29 -------
The C99 standard specifically calls out __STDC_FORMAT_MACROS as a macro which
may be defined before including <inttypes.h>. Therefore, I believe that
warning about this definition is a bug for both C and C++.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
` (2 preceding siblings ...)
2007-11-28 14:29 ` ian at airs dot com
@ 2007-11-28 16:26 ` tromey at gcc dot gnu dot org
2007-11-30 18:24 ` tromey at gcc dot gnu dot org
2007-11-30 18:25 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2007-11-28 16:26 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from tromey at gcc dot gnu dot org 2007-11-28 16:26 -------
Testing a patch.
--
tromey at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |tromey at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
Last reconfirmed|2007-07-26 21:33:20 |2007-11-28 16:26:34
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
` (3 preceding siblings ...)
2007-11-28 16:26 ` tromey at gcc dot gnu dot org
@ 2007-11-30 18:24 ` tromey at gcc dot gnu dot org
2007-11-30 18:25 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2007-11-30 18:24 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from tromey at gcc dot gnu dot org 2007-11-30 18:24 -------
Subject: Bug 32868
Author: tromey
Date: Fri Nov 30 18:24:01 2007
New Revision: 130544
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=130544
Log:
libcpp
PR preprocessor/32868:
* macro.c (_cpp_create_definition): Special case
__STDC_FORMAT_MACROS.
gcc/testsuite
PR preprocessor/32868:
* gcc.dg/cpp/pr32868.c: New file.
Added:
trunk/gcc/testsuite/gcc.dg/cpp/pr32868.c
Modified:
trunk/gcc/testsuite/ChangeLog
trunk/libcpp/ChangeLog
trunk/libcpp/macro.c
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/32868] Don't warn about redefinitions of __STDC_FORMAT_MACROS
2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
` (4 preceding siblings ...)
2007-11-30 18:24 ` tromey at gcc dot gnu dot org
@ 2007-11-30 18:25 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2007-11-30 18:25 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from tromey at gcc dot gnu dot org 2007-11-30 18:24 -------
Fix checked in.
--
tromey at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |FIXED
Target Milestone|--- |4.3.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32868
^ permalink raw reply [flat|nested] 7+ messages in thread
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2007-07-23 17:28 [Bug preprocessor/32868] New: Don't warn about redefinitions of __STDC_FORMAT_MACROS ian at airs dot com
2007-07-26 21:33 ` [Bug preprocessor/32868] " tromey at gcc dot gnu dot org
2007-11-27 20:53 ` tromey at gcc dot gnu dot org
2007-11-28 14:29 ` ian at airs dot com
2007-11-28 16:26 ` tromey at gcc dot gnu dot org
2007-11-30 18:24 ` tromey at gcc dot gnu dot org
2007-11-30 18:25 ` tromey at gcc dot gnu dot org
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