mk: Fix defs for i686-w64-mingw32
Updated jemalloc
Remove build system support for i686-pc-mingw32 triple in favor if i686-w64-mingw32
Fix bad error message copypasta
Add a Rust string ostream for LLVM
Add -C remark for LLVM optimization remarks

Fixes #17116.
Move info into individual modules.
Remove container guide.

This isn't really what guides are for, this information belongs in the
module-level docs.

Fixes #9314.
auto merge of #17196 : vhbit/rust/jemalloc-update, r=thestinger

Fixes #17168
Add support for in-place map for `Vec`s of types with same size

This is implemented using a new struct `PartialVec` which implements the proper
drop semantics in case the conversion is interrupted by an unwind.
PartialVec: Remove TODOs and rename `unwrap` to `into_vec`
Fix some of the issues mentioned in the PR on Github

This specifically includes:
- Fix of the tests
- Remove `transmute` between `Vec`s of different types
Check that the `min_align_of` the both types in a `PartialVec` matches

This is important because the underlying allocator of the `Vec` passes that
information to the deallocator which needs the guarantee that it is the same
parameters that were also passed to the allocation function.
Minimize the public interface and rename it to `map_in_place`
Remove the unused `Iterator` implementation of the private `PartialVec`
Added missing `}` from `map_in_place` rebase
Fixed `map_in_place` tests after rustc upgrade

This replaces the now obsolete syntax `&[]` with `[].as_slice()`.
mk: Don't depend on src/jemalloc/VERSION

This file is touched during the build process and will trigger more rebuilds
than necessary.

Closes #17183
auto merge of #16853 : tbu-/rust/pr_mapinplace, r=aturon

This is implemented using a new struct PartialVec which implements the proper
drop semantics in case the conversion is interrupted by an unwind.

For the old pull requests, see #15302, #16369.
Only pass -fno-use-linker-plugin on Windows

Only pass -fno-use-linker-plugin on Windows where it avoids pulling in
dependencies. Passing it to clang on OS X and Linux would make it fail
though.