also various improvements to the ptr casting fns:
- rename assimilate() to to_unsafe_ptr() (fixes#3110)
- introduce `unsafe::copy_lifetime()` to copy the lifetime from one ptr to another
Region pointers were considered a scalar type, so compare_scalar_type would
get called to compare region pointers in trans. This would fail, since
compare_scalar_type has no case for region pointers.
Changed type_is_scalar to return false for region pointers. This had the side
effect of breaking casts to types of the form &T. To ameliorate that, I added
library functions ptr::assimilate (taking a &T to a *T) and ptr::to_uint
(taking a &T to a uint), both of which use reinterpret_cast.
While I was at it, I removed ty::type_has_resources, which is dead code.
.. there are some additional FIXME nags in net_tcp (L 1012) about blocking
because libuv is holding unsafe ptrs to task local data. the proposed
fix going is not really feasible w/ the current design, IMO, but i'll
leave it there in case someone really wants to make the case without
creating more hassle than it's worth.
.. but the test is kind of broken.. it appears that rust pads structs for
alignment purposes? I can't get the struct to == 28.. that appears to
be the native size of sockaddr_in6.. so we have a size 32 struct, for now.
This comes with a terminology change. All linkage-symbols are 'extern'
now, including rust syms in other crates. Some extern ABIs are
merely "foreign". The term "native" is retired, not clear/useful.
What was "crust" is now "extern" applied to a _definition_. This
is a bit of an overloading, but should be unambiguous: it means
that the definition should be made available to some non-rust ABI.
- change port of tcp server test in uv_ll to avoid conflict w/ test in
net::tcp
- a few places the tcp::read fn is used in test w/ a timeout.. suspend
use of the timeout from here on out.
