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* [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments
@ 2007-08-22 0:34 mec at google dot com
2007-08-22 0:36 ` [Bug preprocessor/33143] " mec at google dot com
` (5 more replies)
0 siblings, 6 replies; 7+ messages in thread
From: mec at google dot com @ 2007-08-22 0:34 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Warning-Options.html#Warning-Options-Wtrigraphs
-Wtrigraphs
Warn if any trigraphs are encountered that might change the meaning of the
program (trigraphs within comments are not warned about). This warning is
enabled by -Wall.
Right now, trigraphs in // comments are not warned about. Trigraphs in /* */
comments are warned about, but should not be. Trigraphs in #if 0 ... #endif
are also warned about, but it would probably be too sticky to change that
behavior.
Example:
mec@hollerith:~/exp-trigraph$ cat z1.cc
#if 0
??-??-
#endif
/*
??-??-
*/
// ??-??-
mec@hollerith:~/exp-trigraph$ /home/mec/gcc-4.2.1/install/bin/g++ -E z1.cc
# 1 "z1.cc"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "z1.cc"
z1.cc:2:1: warning: trigraph ??- ignored, use -trigraphs to enable
z1.cc:2:4: warning: trigraph ??- ignored, use -trigraphs to enable
mec@hollerith:~/exp-trigraph$ /home/mec/gcc-4.3-20070810/install/bin/g++ -E
z1.cc
# 1 "z1.cc"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "z1.cc"
z1.cc:2:1: warning: trigraph ??- ignored, use -trigraphs to enable
z1.cc:2:4: warning: trigraph ??- ignored, use -trigraphs to enable
--
Summary: preprocess should ignore trigraphs in /* */ comments
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: preprocessor
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: mec at google dot com
GCC build triplet: i686-pc-linux-gnu
GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
@ 2007-08-22 0:36 ` mec at google dot com
2007-08-22 0:37 ` pinskia at gcc dot gnu dot org
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: mec at google dot com @ 2007-08-22 0:36 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from mec at google dot com 2007-08-22 00:35 -------
Created an attachment (id=14093)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=14093&action=view)
C++ source file with trigraphs in comments and #if 0
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
2007-08-22 0:36 ` [Bug preprocessor/33143] " mec at google dot com
@ 2007-08-22 0:37 ` pinskia at gcc dot gnu dot org
2007-08-22 1:13 ` joseph at codesourcery dot com
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2007-08-22 0:37 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from pinskia at gcc dot gnu dot org 2007-08-22 00:37 -------
> Trigraphs in #if 0 ... #endif
No that is correct to warn in that context as text inside #if 0 ... #endif are
supposed to be tokens.
Now in multiple line comments, they should not be warned about.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
2007-08-22 0:36 ` [Bug preprocessor/33143] " mec at google dot com
2007-08-22 0:37 ` pinskia at gcc dot gnu dot org
@ 2007-08-22 1:13 ` joseph at codesourcery dot com
2008-04-04 16:29 ` tromey at gcc dot gnu dot org
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: joseph at codesourcery dot com @ 2007-08-22 1:13 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from joseph at codesourcery dot com 2007-08-22 01:13 -------
Subject: Re: preprocess should ignore trigraphs in
/* */ comments
On Wed, 22 Aug 2007, pinskia at gcc dot gnu dot org wrote:
> Now in multiple line comments, they should not be warned about.
Unless of course they affect whether the comment ends or not. That is,
/* ... *??/
/
where the comment ends only if trigraphs are enabled.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
` (2 preceding siblings ...)
2007-08-22 1:13 ` joseph at codesourcery dot com
@ 2008-04-04 16:29 ` tromey at gcc dot gnu dot org
2008-04-04 16:36 ` mec at google dot com
2008-04-04 16:40 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2008-04-04 16:29 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from tromey at gcc dot gnu dot org 2008-04-04 16:28 -------
I tried this test case and as far as I can tell it works as expected.
Can you say what you think is wrong?
I thought perhaps you were misreading the error output. The errors
from the initial report are:
z1.cc:2:1: warning: trigraph ??- ignored, use -trigraphs to enable
z1.cc:2:4: warning: trigraph ??- ignored, use -trigraphs to enable
These are both on line 2. So, we aren't emitting a warning for
the trigraph in the comment.
--
tromey at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at gcc dot gnu dot
| |org
Status|UNCONFIRMED |WAITING
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
` (3 preceding siblings ...)
2008-04-04 16:29 ` tromey at gcc dot gnu dot org
@ 2008-04-04 16:36 ` mec at google dot com
2008-04-04 16:40 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: mec at google dot com @ 2008-04-04 16:36 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from mec at google dot com 2008-04-04 16:36 -------
Doh! You are right, I was confused when I read "z1.cc:2:4" as an error on line
4. Both errors are in line 2, inside the #if block. Sorry for the noise.
--
mec at google dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Resolution| |INVALID
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug preprocessor/33143] preprocess should ignore trigraphs in /* */ comments
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
` (4 preceding siblings ...)
2008-04-04 16:36 ` mec at google dot com
@ 2008-04-04 16:40 ` tromey at gcc dot gnu dot org
5 siblings, 0 replies; 7+ messages in thread
From: tromey at gcc dot gnu dot org @ 2008-04-04 16:40 UTC (permalink / raw)
To: gcc-bugs
------- Comment #6 from tromey at gcc dot gnu dot org 2008-04-04 16:39 -------
It is no trouble. Thanks.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33143
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2008-04-04 16:40 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-08-22 0:34 [Bug preprocessor/33143] New: preprocess should ignore trigraphs in /* */ comments mec at google dot com
2007-08-22 0:36 ` [Bug preprocessor/33143] " mec at google dot com
2007-08-22 0:37 ` pinskia at gcc dot gnu dot org
2007-08-22 1:13 ` joseph at codesourcery dot com
2008-04-04 16:29 ` tromey at gcc dot gnu dot org
2008-04-04 16:36 ` mec at google dot com
2008-04-04 16:40 ` tromey at gcc dot gnu dot org
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