r183883 - Implement core issue 903: only integer literals with value 0 and prvalues of

[Richard Smith]

On Mon, Jun 17, 2013 at 12:23 PM, Jordan Rose <jordan_rose at apple.com> wrote:
>
> On Jun 17, 2013, at 12:20 , Nico Weber <thakis at chromium.org> wrote:
>
> On Mon, Jun 17, 2013 at 9:38 AM, Jordan Rose <jordan_rose at apple.com> wrote:
>>
>> *sigh* I can't say this is the wrong thing to do—in fact, it's the kind of
>> restriction I usually like—but for the record this breaks OS X's (ancient)
>> libstdc++ implementation of <tr1/unordered_map> when compiling under
>> -std=c++11. I don't think that's such an important configuration, though.
>
>
> That means it breaks all programs that try to build in C++11 mode but still
> need to ship to 10.6 (like, say, Chromium). Can this be worked around
> somehow?
>
>
> Will that still be true by the next Xcode release? It's not in 4.6.2, and I
> can watch to make sure it stays out of Xcode 5. Do you really need to build
> your 10.6-compatible binary with trunk Clang in C++11 mode?
>
> Richard, I suppose you could make it a warning...

That's actually pretty tricky, due to its effects on SFINAE, overload
resolution, and so on. But we should be able to add a more limited
workaround which suffices for this specific libstdc++ issue.