[cfe-commits] [PATCH] Re: [cfe-dev] Interest in a -Wusing-namespace-in-headers?

[Nico Weber]

Hi Elliot,

thanks for this feature! It looks like it warns about the following:

$ cat test.h
namespace foo {}
#define USE_NAMESPACE using namespace foo;
$ cat test.cc
#include "test.h"

USE_NAMESPACE
$ clang -c test.cc -Wheader-hygiene
test.cc:3:1: warning: using namespace directive in global context in
header [-Wheader-hygiene]
USE_NAMESPACE
^
In file included from test.cc:1:
./test.h:2:39: note: instantiated from:
#define USE_NAMESPACE using namespace foo;
                                      ^
1 warning generated.

That seems wrong. This pattern is used by ICU.

Nico

On Sat, Mar 26, 2011 at 3:29 PM, Douglas Gregor <dgregor at apple.com> wrote:
>
> On Mar 25, 2011, at 7:30 PM, Elliot Glaysher (Chromium) wrote:
>
>> On Fri, Mar 25, 2011 at 9:40 AM, Peter Collingbourne <peter at pcc.me.uk> wrote:
>>> I believe the correct thing to do is to iterate through
>>> declaration context parents until you reach something that is not a
>>> LinkageSpecDecl, and warn if it is a TranslationUnitDecl.
>>
>> Is something like the attached closer to what you want? This new
>> version recursively walks up the DeclContext chain, and I've
>> integrated all the examples I've seen in this thread into the tests.
>
> Committed in r128352, thanks!
>
>        - Doug
> _______________________________________________
> cfe-commits mailing list
> cfe-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>