Re: C/C++ PATCH to implement -Wpointer-compare warning (PR c++/64767)

[Marek Polacek <polacek at redhat dot com>]

On Fri, Sep 30, 2016 at 01:08:19PM -0600, Martin Sebor wrote:
> On 09/30/2016 11:05 AM, Martin Sebor wrote:
> > > +        permerror (input_location, "ISO C++11 only allows pointer "
> > > +               "conversions for integer literals");
> > 
> > FWIW, I think it would be clearer to either mention the currently
> > selected language version or leave it out completely rather than
> > hardcoding C++11.  When the user specifies -std=c++14 (or later),
> > or when that's the current version used by the compiler, a warning
> > that tells them what C++ 11 allows isn't really relevant (or
> > meaningful), and becomes less so as time goes on.
> 
> Btw., I realize there are other instances where the C++ version
> has been hardcoded and so I should have made it clear that I meant
> my comment as a general suggestion, not as an objection to the patch.
> Sorry if that wasn't apparent.
> 
> I've quickly surveyed some of the existing messages that mention
> a C++ version and found instances where it applies only to the
> referenced version of the standard and prior but not later versions. For
> example:
> 
>   msgid "in C++98 %q+D may not be static because it is a member of a union"
>   msgid "in C++03 a class-key must be used when declaring a friend"
> 
> But I also came across another form that may resolve the concern
> I raised: mentioning the version along with whether it's the first
> or last that supports (or doesn't support) the construct, such as
> "C++11 and above."  Here's one example of it:
> 
>   msgid "in C++11 and above a default constructor can be explicit"
> 
> It might be worth to come up with a convention to adopt in new
> messages and (gradually) change what's already there to use it.

Maybe, no strong opinions, I'll just go with whatever people prefer here.
Though I guess I like those explicit versions because you know when a
particular thing changed.  And when you're using -std=c++14 and the
compiler says C++11, I think that's ok, because C++14 implies C++11.

	Marek