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* [Bug c++/55602] New: Does not generate Error message for redefined macros
@ 2012-12-05 3:44 guojiufu at gmail dot com
2012-12-05 5:00 ` [Bug preprocessor/55602] " pinskia at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: guojiufu at gmail dot com @ 2012-12-05 3:44 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602
Bug #: 55602
Summary: Does not generate Error message for redefined macros
Classification: Unclassified
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: guojiufu@gmail.com
gcc and g++ generate warning message(do not generate any information if there
is '#pragma GCC system_header' is the header) instead an error message for
redefined macros. While in standard it seems require an error.
Second paragraph of section "Macro replacement" in C standard:
--------
An identifier currently defined as an object-like macro shall not be redefined
by another #define preprocessing directive unless the second definition is an
object-like macro definition and the two replacement lists are identical.
Likewise, an identifier currently defined as a function-like macro shall not be
redefined by another #define preprocessing directive unless the second
definition is a function-like macro definition that has the same number and
spelling of parameters, and the two replacement lists are identical.
----------
C++ standard: Second paragraph of section "Macro replacement"
---------
An identifier currently defined as an object-like macro may be redefined by
another #define preprocessing directive provided that the second definition is
an object-like macro definition and the two replacement lists are identical,
otherwise the program is ill-formed. Likewise, an identifier currently defined
as a function-like macro may be redefined by another #define preprocessing
directive provided that the second definition is a function-like macro
definition that has the same number and spelling of parameters, and the two
replacement lists are identical, otherwise the program is ill-formed.
------------------
case:
a.h
----------------
#define A 1
#define A 2
---------------
a.c
---------------
#include "a.h"
int main(){
return A;
}
--------------
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug preprocessor/55602] Does not generate Error message for redefined macros 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com @ 2012-12-05 5:00 ` pinskia at gcc dot gnu.org 2012-12-10 11:58 ` guojiufu at gmail dot com ` (3 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: pinskia at gcc dot gnu.org @ 2012-12-05 5:00 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution| |INVALID --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-12-05 05:00:05 UTC --- Use -pedantic-errors. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug preprocessor/55602] Does not generate Error message for redefined macros 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com 2012-12-05 5:00 ` [Bug preprocessor/55602] " pinskia at gcc dot gnu.org @ 2012-12-10 11:58 ` guojiufu at gmail dot com 2012-12-10 11:59 ` guojiufu at gmail dot com ` (2 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: guojiufu at gmail dot com @ 2012-12-10 11:58 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602 --- Comment #2 from Jeff Guo <guojiufu at gmail dot com> 2012-12-10 11:57:57 UTC --- -pedantic-errors is helpful if the redefined macros not guarded by "#pragma GCC system_header" --a.h -- #pragma GCC system_header #define A 1 #define A 2 -----a.c---- #include "a.h" int main(){ return A; } ---------------- ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug preprocessor/55602] Does not generate Error message for redefined macros 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com 2012-12-05 5:00 ` [Bug preprocessor/55602] " pinskia at gcc dot gnu.org 2012-12-10 11:58 ` guojiufu at gmail dot com @ 2012-12-10 11:59 ` guojiufu at gmail dot com 2012-12-10 12:02 ` guojiufu at gmail dot com 2012-12-26 2:26 ` guojiufu at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: guojiufu at gmail dot com @ 2012-12-10 11:59 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602 --- Comment #3 from Jeff Guo <guojiufu at gmail dot com> 2012-12-10 11:59:07 UTC --- Above case is still no error message reported even with -pedantic-errors ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug preprocessor/55602] Does not generate Error message for redefined macros 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com ` (2 preceding siblings ...) 2012-12-10 11:59 ` guojiufu at gmail dot com @ 2012-12-10 12:02 ` guojiufu at gmail dot com 2012-12-26 2:26 ` guojiufu at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: guojiufu at gmail dot com @ 2012-12-10 12:02 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602 Jeff Guo <guojiufu at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |VERIFIED Resolution|INVALID |WONTFIX --- Comment #4 from Jeff Guo <guojiufu at gmail dot com> 2012-12-10 12:02:29 UTC --- may GCC report error message for redefined macro if -pedantic-errors specified for system headers? ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug preprocessor/55602] Does not generate Error message for redefined macros 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com ` (3 preceding siblings ...) 2012-12-10 12:02 ` guojiufu at gmail dot com @ 2012-12-26 2:26 ` guojiufu at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: guojiufu at gmail dot com @ 2012-12-26 2:26 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55602 Jeff Guo <guojiufu at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|VERIFIED |CLOSED --- Comment #5 from Jeff Guo <guojiufu at gmail dot com> 2012-12-26 02:26:34 UTC --- using -pedantic-errors is helpful ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-12-26 2:26 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2012-12-05 3:44 [Bug c++/55602] New: Does not generate Error message for redefined macros guojiufu at gmail dot com 2012-12-05 5:00 ` [Bug preprocessor/55602] " pinskia at gcc dot gnu.org 2012-12-10 11:58 ` guojiufu at gmail dot com 2012-12-10 11:59 ` guojiufu at gmail dot com 2012-12-10 12:02 ` guojiufu at gmail dot com 2012-12-26 2:26 ` guojiufu at gmail dot com
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