[v3] complex functions with expression template reals

[Paolo Carlini]

On 02/23/2014 11:32 AM, Marc Glisse wrote:
> Hello,
>
> looking at this question:
> http://stackoverflow.com/q/21737186/1918193
> I was surprised to see that libstdc++'s std::complex basically just 
> works with user-defined types, even weird expression template ones, 
> although that's not a supported use afaik.
>
> The only functions that fail seem to be exp and pow, both because they 
> call polar with two arguments that have different (expression) types.
>
> I am not proposing to make this a supported use, but the cost of this 
> small patch seems very low, and if it makes a couple users happy...
>
> Regtested with no problem on x86_64-linux-gnu, ok for stage 1?
I would even be in favor of applying it now. Can we figure out simple 
(ie, not relying on boost...) testcases too?

Paolo.