Re: c/7860: few new suggested warnings

Re: c/7860: few new suggested warnings

[Andrew Pinski]

The following reply was made to PR c/7860; it has been noted by GNATS.

From: Andrew Pinski <pinskia@physics.uc.edu>
To: jhi@iki.fi
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: c/7860: few new suggested warnings
Date: Sun, 8 Sep 2002 18:57:44 -0400

 Here is a copy of the file since the file was in macbinary format that 
 some people cannot decode:
 -Wcppcomment
 
          Warn about C++ style comments // like this.
 
 -Wgnuextensions
 
          Warn about the use of any GNU extensions.
 
 -Wpointer-implicit-sign
 
          Warn if a pointer is implicitly cast between signed
          and unsigned, for example:
 
              int foo(unsigned char *s) {
                  ...
              }
                  ...
                  char *s;
                  ...
                  foo(s);
 
          (enabled by -ansi)
 
 -Wenum-implicit-int
 
          Warn if enums are implicitly used as integers, for example
 
          enum e { E1, E2, E3 };
          ...
          enum e e1 = 0;  /* Warn. */
          enum e e2 = E2;
          enum e e3, e4;
          e3 = e1 + 1;    /* Warn. */
          e2++;           /* Warn. */
          e4 = e3 & ~E2;  /* Warn. */
 
 -Wenum-trailing-comma
 
          Warn if enum declaration has a trailing comma.
 
          (enabled by -pedantic)
 
 -Wcpp-spurious-tokens
 
          Warn if there are any unnecessary tokens after preprocessor 
 commands,
          for example
 
              #endif STUFF
 
          (enabled by -pedantic)
 

Re: c/7860: few new suggested warnings

[Jarkko Hietaniemi]

The following reply was made to PR c/7860; it has been noted by GNATS.

From: Jarkko Hietaniemi <jhi@iki.fi>
To: jsm28@gcc.gnu.org, gcc-bugs@gcc.gnu.org, gcc-prs@gcc.gnu.org,
   jsm28@cam.ac.uk, nobody@gcc.gnu.org, gcc-gnats@gcc.gnu.org
Cc:  
Subject: Re: c/7860: few new suggested warnings
Date: Mon, 16 Sep 2002 17:08:55 +0300

 Also, since most of the suggested new warnings are about rather simple
 code portability glitches (like the // and the lvalue casts), adding
 as many of them as possible to be under the -Wall would be nice.
 Of course, this has to be balanced against people not liking their
 previously -Wall-happy code starting to whine...
 
 -- 
 Jarkko Hietaniemi <jhi@iki.fi> http://www.iki.fi/jhi/ "There is this special
 biologist word we use for 'stable'.  It is 'dead'." -- Jack Cohen

Re: c/7860: few new suggested warnings

[jsm28]

Synopsis: few new suggested warnings

State-Changed-From-To: open->analyzed
State-Changed-By: jsm28
State-Changed-When: Sun Sep 15 13:35:12 2002
State-Changed-Why:
    Of those mentioned, -Wgnuextensions already exists as
    -pedantic and -Wcpp-spurious-tokens already exists as
    -Wendif-labels (on by default).  The others may be useful
    to add.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7860

Re: c/7860: few new suggested warnings

[Jarkko Hietaniemi]

The following reply was made to PR c/7860; it has been noted by GNATS.

From: Jarkko Hietaniemi <jhi@iki.fi>
To: gcc-gnats@gcc.gnu.org
Cc:  
Subject: Re: c/7860: few new suggested warnings
Date: Sun, 15 Sep 2002 18:22:53 +0300

 I just remembered one more warning that would be useful to have
 available on its own, outside of -pedantic:
 
 -Wcast-lvalue
 
 	Warn if a cast expression is used as an lvalue.
 
 -- 
 Jarkko Hietaniemi <jhi@iki.fi> http://www.iki.fi/jhi/ "There is this special
 biologist word we use for 'stable'.  It is 'dead'." -- Jack Cohen

Re: c/7860: few new suggested warnings

[Jarkko Hietaniemi]

The following reply was made to PR c/7860; it has been noted by GNATS.

From: Jarkko Hietaniemi <jhi@iki.fi>
To: Andrew Pinski <pinskia@physics.uc.edu>
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: c/7860: few new suggested warnings
Date: Mon, 9 Sep 2002 01:59:57 +0300

 > Here is a copy of the file since the file was in macbinary format that 
 > some people cannot decode:
 
 Oops, sorry about that.  I blame the browser (yes, I'm a on Mac).
 
 -- 
 Jarkko Hietaniemi <jhi@iki.fi> http://www.iki.fi/jhi/ "There is this special
 biologist word we use for 'stable'.  It is 'dead'." -- Jack Cohen

c/7860: few new suggested warnings

[jhi]

>Number:         7860
>Category:       c
>Synopsis:       few new suggested warnings
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Sun Sep 08 15:06:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Jarkko hietaniemi
>Release:        any
>Organization:
>Environment:
any
>Description:
I was the release manager of the Perl 5.8.0 project.  As a part of that, we did a lot of test building on many platforms to clean up the C source code of Perl, and saw a lot of warnings about dubious practices that gcc didn't catch.

Therefore, I would like to suggest adding these warnings to some upcoming gcc release. 

Some of the suggested warnings are already there but one needs either -ansi or -pedantic to enable them, and in some projects (including Perl) this is not an option, therefore having the warnings still available separately would be a good thing.  (In general, maybe "disassembling" -ansi and -pedantic into separate options would be beneficial?)

Some of the suggested warnings do not seem to be there and therefore they would be completely new.

The suggested warnings are in the file attachment.
>How-To-Repeat:

>Fix:
Implement the new warnings :-)
>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Type: application/x-macbinary; name="gccneedwarn"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="gccneedwarn"

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