rustc: Prepare the `atomics` feature for wasm
This commit adds a few changes for atomic instructions on the
`wasm32-unknown-unknown` target. Atomic instructions are not yet stable in
WebAssembly itself but there are multiple implementations and LLVM has support
for the proposed instruction set, so let's work on exposing it!
Here there are a few inclusions:
* The `atomics` feature was whitelisted for LLVM, allowing code in Rust to
enable/disable/gate on this.
* The `singlethread` option is turned off for wasm when the `atomics` feature is
enabled. This means that by default wasm won't be lowering with atomics, but
when atomics are enabled globally we'll turn off single-threaded mode to
actually codegen atomics. This probably isn't what we'll want in the long term
but for now it should work.
* Finally the maximum atomic width is increased to 64 to reflect the current
wasm spec.
* When encountering EOF, point at the last opening brace that does not
have the same indentation level as its close delimiter.
* When encountering the wrong type of close delimiter, point at the
likely correct open delimiter to give a better idea of what went
wrong.
Fixes a problem where submodules could not be cloned under some git
configurations. Specifically, when url.git@github.com:.insteadOf =
https://github.com/ is set.
Update Cargo.lock
This also includes major version bumps for the rand crate used by core, std, and alloc tests, among other crates (regex, etc.) used elsewhere. Since these are all internal there should be no user-visible changes.
r? @alexcrichton
Allow to check if sync::Once is already initialized
Hi!
I propose to expose a way to check if a `Once` instance is initialized.
I need it in `once_cell`. `OnceCell` is effetively a pair of `(Once, UnsafeCell<Option<T>>)`, which can set the `T` only once. Because I can't check if `Once` is initialized, I am forced to add an indirection and check the value of ptr instead:
8127a81976/src/lib.rs (L423-L429)8127a81976/src/lib.rs (L457-L461)
The `parking_lot`'s version of `Once` exposes the state as an enum: https://docs.rs/parking_lot/0.6.3/parking_lot/struct.Once.html#method.state.
I suggest, for now, just to add a simple `bool` function: this fits my use-case perfectly, exposes less implementation details, and is forward-compatible with more fine-grained state checking.
commit 6c10142251 ("Update LLVM submodule") disabled the lldb build.
This patch updates the lldb and clang submodules to once again build
against the LLVM that is included in the Rust tree, and reverts the
.travis.yml changes from that patch.
It now does one hash table lookup per basic block, instead of one per
statement. This is worthwhile because this function is hot for NLL
builds of `ucd`.
A few cleanups and minor improvements to save_analysis
- calculate the capacity of some `Vec`s
- change`to_owned()` to `clone()` for the purposes of `lower_attributes`
- remove a superfluous `clone()`
- prefer `to_owned()` to `to_string()`
- a few other minor improvements
