Added home_for_io_with_sched variant. Temporarily making IO unkillable.
Add PointerKind to LpDeref
Prohibit assignment to `&mut` pointers that are found in frozen or borrowed locations.

Fixes #8625.
Make getopts count (and thus align/paginate) in terms of codepoints not bytes.
Rename {Reader,Writer}ByteConversions methods

The method names in std::rt::io::extensions::WriterByteConversions are
the same as those in std::io::WriterUtils and a resolve error causes
rustc to fail after trying to find an impl of io::Writer instead of
trying to look for rt::io::Writer as well.

Same goes for ReaderByteConversions.
Fix some vector function failure tests. Closes #8698
Allow metadata to be not compressed
std: Reduce TLS access
Define cfg(rtopt) when optimizing. Turn off runtime sanity checks

Naturally, and sadly, turning off sanity checks in the runtime is
a noticable performance win. The particular test I'm running goes from
~1.5 s to ~1.3s.

Sanity checks are turned *on* when not optimizing, or when cfg
includes `rtdebug` or `rtassert`.
std: Convert some assert!s to rtassert!
Don't copy metadata after loading
Added note that there is still more to do on 5516.

Also added regression test for the byte vs codepoint issues that the
previous commit fixes.
rustllvm: Specify hard floats for gnueabihf.
librustc: Always use session target triple.
Remove ifmt hax and implement fprintf
Implement a wrapper macro around fprintf -- ifmtf
Settle on the format/write/print family of names
std: More TLS micro-optimization
std::rt: Optimize TLS use in change_task_context
std::rt: Remove extra boxes from MessageQueue and SleeperList