[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[gdr at gcc dot gnu dot org]

------- Comment #6 from gdr at gcc dot gnu dot org  2005-11-26 09:08 -------
(In reply to comment #0)
> Some warning options trigger warnings in standard C++ headers, rendering
> -Werror 
> unusable. This can be seen with a simple example:
> 
> #include <list>
> int main()
> {
>    std::list<int> foo;
> }
> 
> 
> When compiling with g++ -Weffc++ -Werror foo.cpp a lot of warnings about STL 
> classes are emitted. 
> While the gcc manual already mentions that -Weffc++ could produce spurious 
> warnings, the same problems occurs with -Winline (I can try to produce a
> minimal 
> test case if required). I think the compiler should ignore warnings in these 
> files, as the user cannot fix them.
> 

The real problem, as I understand it, is that we used to forget to copy
the in_system_header marker from templates when doing instantiations.
I think Mark Mitchell fixed that behaviour recently.
At any case, mainline GCC (4.2.x) issues no warning with your testcase.

-- Gaby


-- 

gdr at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.2.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14172

[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
   Last reconfirmed|2004-11-14 07:13:14         |2005-02-22 01:44:32
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14172

[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[matthew at linuxfromscratch dot org]

------- Additional Comments From matthew at linuxfromscratch dot org  2004-11-23 10:18 -------
Would someone mind commenting on what needs to happen with this bug please?  My
testing has shown that the behaviour of -Weffc++ is correct with regard to
system headers.  The problem is that some of the headers in
/usr/include/c++/$gcc-version/bits aren't treated as system headers.  This
doesn't just affect -Weffc++, it actually affects *all* warning options (e.g.
-Wunreachable-code is often triggered by such headers IIRC).  Does the bug
summary need changing?  What about the component?  (I suspect this is now in the
realm of libstdc++).  It seems closely related to bug 12854.

Thanks,

Matt

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14172

[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[matthew at linuxfromscratch dot org]

------- Additional Comments From matthew at linuxfromscratch dot org  2004-11-19 07:51 -------
Putting trivial test cases together, both with and without #pragma GCC
system_header in them, the compiler behaves correctly.  Compiling the test case
in comment 1 shows results in 24 lines of warnings, none of which the user can
do anything about, as they all relate to the _internal_ headers in
/usr/include/c++/${gcc-version}/bits.  So, system headers appear to be treated
correctly (e.g. <list> has the #pragma GCC system_header), but why are the
headers in bits/ not treated as system headers?  Neither adding the pragma to
those headers, nor adding "-isystem /usr/include/c++/${gcc-version}/bits" to the
command line appeared to have any effect.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14172

[Bug c++/14172] g++ should not emit effc++ warnings in system headers

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2004-02-17 16:29 -------
Useful? For the user? I don't see how. I'm inclined to accept this as an 
enhancement request. It's a one liner for each -Weffc++ entry.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-02-17 16:29:20
               date|                            |
            Summary|g++ should ignore warnings  |g++ should not emit effc++
                   |in STL headers              |warnings in system headers


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14172