[patch] No allocation for empty unordered containers

[François Dumont]

On 12/08/2014 21:39, Marc Glisse wrote:
> On Tue, 12 Aug 2014, François Dumont wrote:
>
>>    Based on your feedbacks I think we should stay with just targeting 
>> good QoI by not allocating on default construction. As I said the 
>> noexcept qualification would need to not conform strictly to the 
>> Standard.
>
> The standard explicitly says that you may add noexcept wherever you 
> like. It is constexpr that we can only add in GNU mode.
>
     That's not what I meant. For unordered containers there is no real 
default constructor. it is in fact a constructor with parameters which 
have all default values. This is why you can only say that it won't 
throw at runtime and so you can't qualify it noexcept.

François