This moves the locking/waiting methods to returning an RAII struct instead of
relying on closures. Additionally, this changes the methods to all take
'&mut self' to discourage recursive locking. The new method to block is to call
`wait` on the returned RAII structure instead of calling it on the lock itself
(this enforces that the lock is held).

At the same time, this improves the Mutex interface a bit by allowing
destruction of non-initialized members and by allowing construction of an empty
mutex (nothing initialized inside).

This PR removes almost all `_iter` suffixes in various APIs of the codebase that return Iterators, as discussed in #9440.

As a summarize for the intend behind this PR:

- Iterators are the recommended way to provide a potentially lazy list of values, no need to name them painfully verbose. If anything, functions that return a specific container type should have more verbose names.
- We have a static type system, so no need to encode the return value of a constructor function into its name.

Following is a possibly incomplete list of all renamings I performed in the codebase. For a few of them I'm a bit unsure whether the new name still properly expresses their functionality, so feedback would be welcome:

~~~
&str : word_iter()             -> words()
       line_iter()             -> lines()
       any_line_iter()         -> lines_any()
       iter()                  -> chars()
       char_offset_iter()      -> char_indices()
       byte_iter()             -> bytes()
       split_iter()            -> split()
       splitn_iter()           -> splitn()
       split_str_iter()        -> split_str()
       split_terminator_iter() -> split_terminator()
       matches_index_iter()    -> match_indices()
       nfd_iter()              -> nfd_chars()
       nfkd_iter()             -> nfkd_chars()
      
&[T] : split_iter()        -> split()
       splitn_iter()       -> splitn()
       window_iter()       -> windows()
       chunk_iter()        -> chunks()
       permutations_iter() -> permutations()
      
extra:bitv::Bitv :  rev_liter()    -> rev_iter()
                    common_iter()  -> commons()
                    outlier_iter() -> outliers()

extra::treemap::{...} : lower_bound_iter() -> lower_bound()
                        upper_bound_iter() -> upper_bound()
                       
std::trie::{...} : bound_iter()       -> bound()
                   lower_bound_iter() -> lower_bound()
                   upper_bound_iter() -> upper_bound()

rustpkg::package_id::{...} : prefixes_iter() -> prefixes()

std::hashmap::{...} : difference_iter()           -> difference()
                      symmetric_difference_iter() -> symmetric_difference()
                      intersection_iter()         -> intersection()
                      union_iter()                -> union()
                     
std::path::{posix, windows} : component_iter()     -> components()
                              str_component_iter() -> str_components()

... not showing all identical renamings for reverse versions
~~~

---

I'm also planning a few more changes, like removing all unnecessary `_rev` constructors (#9391), or reducing the `split` variants on `&str` to a more versatile and concise system.

This patchset fixes some parts broken on Win64.

This also adds `--disable-pthreads` flags to llvm on mingw-w64 archs (both 32-bit and 64-bit, not mingw) due to bad performance. See #8996 for discussion.

This patchset makes warning if crate-level attribute is used at other places, obsolete attributed is used, or unknown attribute is used, since they are usually from mistakes.

Closes #3348

This is needed so that the FFI works as expected on platforms that don't
flatten aggregates the way the AMD64 ABI does, especially for `#[repr(C)]`.

This moves more of `type_of` into `trans::adt`, because the type might
or might not be an LLVM struct.

Closes #10308.

This also enables two tests properly.

This also moves `#[auto_{en,de}code]` checker from syntax to lint.

This moves the locking/waiting methods to returning an RAII struct instead of
relying on closures. Additionally, this changes the methods to all take
'&mut self' to discourage recursive locking. The new method to block is to call
`wait` on the returned RAII structure instead of calling it on the lock itself
(this enforces that the lock is held).

At the same time, this improves the Mutex interface a bit by allowing
destruction of non-initialized members and by allowing construction of an empty
mutex (nothing initialized inside).

Without this the assert in <tt>rust_malloc_ip6_addr</tt> is triggered as it expects a correctly formatted IPv6 address.

Implement various traits (IterBytes and extra's Encodable and Decodable) for Rc<T> when T alreay implements the trait.

Add an implementation of Encodable and Decodable for Rc. This will be needed to use Rc in place of @ in libsyntax.

We want a 1000 element array, not a 2 element array

This is a behavioral difference in libuv between different platforms in
different situations. It turns out that libuv on windows will immediately
allocate a buffer instead of waiting for data to be ready. What this implies is
that we must have our custom data set on the handle before we call
uv_read_start.

I wish I knew of a way to test this, but this relies to being on the windows
platform *and* reading from a true TTY handle which only happens when this is
actually attached to a terminal. I have manually verified this works.

Closes #10645

Closes #10623

Fixes #3614.

Fixes #3614.

We want a 1000 element array, not a 2 element array

Currently, the parser doesn't give any context when it finds an unclosed
delimiter and it's not EOF. Report the most recent unclosed delimiter, to help
the user along.

Closes #10636

This is both useful for performance (otherwise logging is unbuffered), but also
useful for correctness. Because when a task is destroyed we can't block the task
waiting for the logger to close, loggers are opened with a 'CloseAsynchronously'
specification. This causes libuv do defer the call to close() until the next
turn of the event loop.

If you spin in a tight loop around printing, you never yield control back to the
libuv event loop, meaning that you simply enqueue a large number of close
requests but nothing is actually closed. This queue ends up never getting
closed, meaning that if you keep trying to create handles one will eventually
fail, which the runtime will attempt to print the failure, causing mass
destruction.

Caching will provide better performance as well as prevent creation of too many
handles.

Closes #10626

This is needed so that the FFI works as expected on platforms that don't
flatten aggregates the way the AMD64 ABI does, especially for `#[repr(C)]`.

This moves more of `type_of` into `trans::adt`, because the type might
or might not be an LLVM struct.