Inline defaulted functions

[Thomas1664]

In the case of out of line defaulted move constructors this prevented some types from being nothrow movable.
Please also note that associative containers aren't nothrow movable on MSVC. One has to explicitly mark default move constructors as noexcept for types containing associative containers to make them nothrow movable.

[BillyONeal]

This is reverting an explicit design choice to favor build throughput by not needing the definition of these functions spammed out into every object file in places where performance does not matter.

Do you have data showing this is meaningful for customers?

[Thomas1664]

This is reverting an explicit design choice to favor build throughput by not needing the definition of these functions spammed out into every object file in places where performance does not matter.

Do you have data showing this is meaningful for customers?

The main goal of this PR is to avoid not marking move constructors as noexcept in the case of out of line defaulted move constructors. I highly doupt that inlining vs not inlining makes a difference at compile time or run time.

Edit:

Furthermore, implicitly declared move constructors are always inlined: https://en.cppreference.com/w/cpp/language/move_constructor Following your design, you'd have to manually default all (move) constructors out of line.

[BillyONeal]

@ras0219-msft @data-queue @vicroms @JavierMatosD and I discussed this today and we are happy with this so long as defaulting in the header does not require exposing additional dependencies in headers (e.g. in pimpl patterns like this:

// header.hpp

#include <memory>

struct impl;

struct ptr {
    std::unique_ptr<impl> instance;
    // ~ptr() = default; // error: impl is incomplete, how do I ~impl?
    ~ptr();
};

)

[BillyONeal]

Thanks :)