Improved the search by including a levenshtein distance calculation which enables the docs search function to be more forgiving for spelling mistakes
Updated the licensing information for the Levenshtein distance function
Documentation examples for LruCache.
Cleanup LruCache doc.
Improved the tags impl regex
Make most of the failure functions take &(&'static str, uint)

Passing one pointer takes less code than one pointer and an integer.
Put the struct passed to unwinding functions into a static

Produces very clean asm, but makes bigger binaries.
Sort trait bounds.

Closes #6334
librustc: Disallow mutation and assignment in pattern guards, and modify
the CFG for match statements.

There were two bugs in issue #14684. One was simply that the borrow
check didn't know about the correct CFG for match statements: the
pattern must be a predecessor of the guard. This disallows the bad
behavior if there are bindings in the pattern. But it isn't enough to
prevent the memory safety problem, because of wildcards; thus, this
patch introduces a more restrictive rule, which disallows assignments
and mutable borrows inside guards outright.

I discussed this with Niko and we decided this was the best plan of
action.

This breaks code that performs mutable borrows in pattern guards. Most
commonly, the code looks like this:

    impl Foo {
        fn f(&mut self, ...) {}
        fn g(&mut self, ...) {
            match bar {
                Baz if self.f(...) => { ... }
                _ => { ... }
            }
        }
    }

Change this code to not use a guard. For example:

    impl Foo {
        fn f(&mut self, ...) {}
        fn g(&mut self, ...) {
            match bar {
                Baz => {
                    if self.f(...) {
                        ...
                    } else {
                        ...
                    }
                }
                _ => { ... }
            }
        }
    }

Sometimes this can result in code duplication, but often it illustrates
a hidden memory safety problem.

Closes #14684.

[breaking-change]
core: Remove unneeded cfgs
std: Use correct conventions for statics in macros
Revert "Use fewer instructions for `fail!`"

This reverts commit c61f9763e2e03afbe62445877ceb3ed15e22e123.

Conflicts:
	src/librustrt/unwind.rs
	src/libstd/macros.rs
librustc: Use builder for llvm attributes.
librustc: Use dereferenceable attribute instead of nonnull where we can.
Implement PartialEq/Eq/Clone/Hash/FromIterator/Extendable for SmallIntMap and Show/Clone for TrieMap and TrieSet
Fix a typo in SmallIntMap documentation
rustllvm: Stub out some functions for llvm < 3.5
fix small typo in guide-lifetimes
Relicense shootout-k-nucleotide.rs

Everyone agreed except @thestinger. As @thestinger contribution on this file is trivial,
we can relicense it.

Related to #14248, close #15330
auto merge of #15996 : nham/rust/smallintmap_not_hashmap, r=sanxiyn

SmallIntMap doesn't involve hashing?