Improved the tags impl regex
Sort trait bounds.

Closes #6334
Add a split_at method to slice::ImmutableVector

This method is similar to the mut_split_at method of slice::MutableVector.
native: Fix utime() for windows

Apparently the units are in milliseconds, not in seconds!
Remove the "NFKC clause" in the reference manual.

The reference manual said that code is interpreted as UTF-8 text and a
implementation will normalize it to NFKC. However, rustc doesn't do
any normalization now.

We may want to do any normalization for symbols, but normalizing whole
text seems harmful because doing so loses some sort of information even
if we choose a non-K variant of normalization.

I'd suggest removing "normalized to Unicode normalization form NFKC"
phrase for the present so that the manual represents the current state
properly. When we address the problem (with a RFC?), then the manual
should be updated.

Closes #12388.

Reference: https://github.com/rust-lang/rust/issues/2253

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
doc: make the sentence make more sense
Gedit/GTKSourceView: Add macro syntax highlighting.
Rename guessing_game.rs to main.rs in guide
docs: Fix typo in tutorial.
doc: Fix the 30-minute intro to use += operator.

The 30-minute intro had a comment mentioning that `+=` will be included in the future. It's already included, and this fixes it to use `+=`.
libgetopts: tweak HasHarg/Occur docs.
rustdoc: Use more descriptive description metadata.

This text appears in and improves search results.

cc #12466
rustdoc: Put field instantiation in declaration order.

cc #12466
rustdoc: Emit keywords for all crate pages

cc #12466
rustdoc: Just "stability" instead of "stability dashboard"

The words "stability dashboard" take up too much space on small screens.
Clarify Argument docs.

Fixes #15830.
stabilize atomics (now atomic)

This commit stabilizes the `std::sync::atomics` module, renaming it to
`std::sync::atomic` to match library precedent elsewhere, and tightening
up behavior around incorrect memory ordering annotations.

The vast majority of the module is now `stable`. However, the
`AtomicOption` type has been deprecated, since it is essentially unused
and is not truly a primitive atomic type. It will eventually be replaced
by a higher-level abstraction like MVars.

Due to deprecations, this is a:

[breaking-change]
Fix valgrind.h for Win64.
_WIN32 is defined for 64-bit builds as well, so test for _WIN64 first.
Ensure that Registers struct is 16-byte aligned on x86_64.
This is important when building with --disable-jemalloc: unlike jemalloc,  msvcrt does not align on 16 bytes unless asked to.
libnative should not mess with stack limits in the TIB.  Only libgreen has a legitimate need to set them.