Add rustup.sh to the repo

Just to have it somewhere to point to. Updating it will not
automatically update the one on static.rust-lang.org.
improve clone_from_slice performance
add intmax
Add assume intrinsic

Adds an `assume` intrinsic that gets translated to llvm.assume. It is
used on a boolean expression and allows the optimizer to assume that
the expression is true.

This implements #18051.
Improve documentation of assume intrinsic.
Guide: articulate the advantages of ownership over garbage collection.

Explain the primary disadvantage of garbage collection is runtime
overhead and unpredictable pauses.  Elucidate where the name "race
condition" comes from.  Emphasize that Rust can guarantee your code is
free of race conditions and other memory errors, with no runtime
overhead.
rustdoc: hide private traits in strip-private pass

Fix #16563
Fix issue #17848 (Questionable advice in bug report instructions)
Add test for issue #17594
debuginfo: Gate all LLDB debuginfo tests on a minimum LLDB version being available
debuginfo: Make some path LLDB-related paths in the test runner absolute to help the build bots.
debuginfo: Enable LLDB test suite on Darwin.
debuginfo: Let LLDB tests run in parallel again since our min-supported version has no problems with that.
debuginfo: Print more output in lldb_batchmode.py for better error logs.
Guide: Adapt range values to variable name
Guide: Change >= to > in closure
auto merge of #18230 : cakebaker/rust/adapt_range_value_to_variable_name, r=steveklabnik

 The variable name <code>one_to_one_hundred</code> implies that it will contain a collection with the values from 1 to 100, but the collection contains the values from 0 to 99. This patch changes the ranges to produce a collection with the values from 1 to 100.
Use local cache when there are unbound type variables and where clauses in scope.

Fixes #18209.
auto merge of #17846 : tomjakubowski/rust/rustdoc-hide-private-traits, r=alexcrichton

Fix #16563
auto merge of #18092 : michaelwoerister/rust/lldb-test-versioning, r=alexcrichton

Now that there are build bots with a stable enough LLDB version on OSX we can finally let the tests run on every PR!
:joy_cat: