[cfe-dev] Interest in a -Wusing-namespace-in-headers?

[Douglas Gregor]

On Mar 16, 2011, at 4:51 PM, Daniel James wrote:

> On 16 March 2011 22:56, Douglas Gregor <dgregor at apple.com> wrote:
>> 
>> IIRC, libstdc++ does it with "strong using" directives (which Clang doesn't support).
> 
> Sorry, I meant libc++. It certainly uses using directives.

I see using directives only at function scope in libc++ (and we certainly don't want to warn about those). But anyway, I agree with your meta-point.

>> Boost, I assume, only does this for using declarations; that's not what the patch is about.
> 
> No, because we don't know if the function is in the std namespace, so
> we can't use a using declaration. They're used for other reasons as
> well.
> 
> But it doesn't really matter where it is or isn't used. What matters
> is that a properly scoped import is usually safe, and warning about
> one would be counter productive.


I agree.

	- Doug