Re: [boost] [review] Review of Outcome (starts Fri-19-May)

Subject: Re: [boost] [review] Review of Outcome (starts Fri-19-May)
From: Peter Dimov (lists_at_[hidden])
Date: 2017-05-19 14:39:37

Niall Douglas wrote:
> > https://github.com/ned14/boost.outcome/blob/master/include/boost/outcome/v1.0/error_code_extended.hpp#L47

> The hack is the above. We cache the address of the canonical singleton, 
> ...

Hm. I must be missing something.

    BOOSTLITE_NOINLINE inline const std::error_category &_generic_category()
    {
        const std::error_category &c = stl11::generic_category();
        return c;
    }

This doesn't cache anything. It just calls stl11::generic_category() and 
returns the result.

> The resulting assembler generated is greatly improved on MSVC, a single 
> result<T> shrinks from ~260 opcodes to less than 5.

Would be nice if we could see that demonstrated on godbolt.org.