rustbuild: Tweak LLVM distribution layout
This commit tweaks the layout of a few components that we distribute to
hopefully fix across all platforms the recent issues with LLD being unable to
find the LLVM shared object. In #53245 we switched to building LLVM as a dynamic
library, which means that LLVM tools by default link to LLVM dynamically rather
than statically. This in turn means that the tools, at runtime, need to find the
LLVM shared library.
LLVM's shared library is currently distributed as part of the rustc component.
This library is located, however, at `$sysroot/lib`. The LLVM tools we ship are
in two locations:
* LLD is shipped at `$sysroot/lib/rustlib/$host/bin/rust-lld`
* Other LLVM tools are shipped at `$sysroot/bin`
Each LLVM tool has an embedded rpath directive indicating where it will search
for dynamic libraries. This currently points to `../lib` and is presumably
inserted by LLVM's build system. Unfortunately, though, this directive is only
correct for the LLVM tools at `$sysroot/bin`, not LLD!
This commit is targeted at fixing this situation by making two changes:
* LLVM tools other than LLD are moved in the distribution to
`$sysroot/lib/rustlib/$host/bin`. This moves them next to LLD and should
position them for...
* The LLVM shared object is moved to `$sysroot/lib/rustlib/$host/lib`
Together this means that all tools should natively be able to find the shared
object and the shared object should be installed all the time for the various
tools. Overall this should...
Closes#53813
Added in #52149 the discussion in #53514 is showing how we may not want to
actually add this attribute to the atomic types. While we continue to
debate #53514 this commit reverts the addition of the `transparent` attribute.
This should be a more conservative route which leaves us the ability to tweak
this in the future but in the meantime allows us to continue discussion as well.
Restore lldb build
commit 6c10142251 ("Update LLVM submodule") disabled the lldb build.
This patch updates the lldb and clang submodules to once again build
against the LLVM that is included in the Rust tree, and reverts the
.travis.yml changes from that patch.
This commit tweaks the layout of a few components that we distribute to
hopefully fix across all platforms the recent issues with LLD being unable to
find the LLVM shared object. In #53245 we switched to building LLVM as a dynamic
library, which means that LLVM tools by default link to LLVM dynamically rather
than statically. This in turn means that the tools, at runtime, need to find the
LLVM shared library.
LLVM's shared library is currently distributed as part of the rustc component.
This library is located, however, at `$sysroot/lib`. The LLVM tools we ship are
in two locations:
* LLD is shipped at `$sysroot/lib/rustlib/$host/bin/rust-lld`
* Other LLVM tools are shipped at `$sysroot/bin`
Each LLVM tool has an embedded rpath directive indicating where it will search
for dynamic libraries. This currently points to `../lib` and is presumably
inserted by LLVM's build system. Unfortunately, though, this directive is only
correct for the LLVM tools at `$sysroot/bin`, not LLD!
This commit is targeted at fixing this situation by making two changes:
* LLVM tools other than LLD are moved in the distribution to
`$sysroot/lib/rustlib/$host/bin`. This moves them next to LLD and should
position them for...
* The LLVM shared object is moved to `$sysroot/lib/rustlib/$host/lib`
Together this means that all tools should natively be able to find the shared
object and the shared object should be installed all the time for the various
tools. Overall this should...
Closes#53813
If a suitable value of Python is not on PATH, one can still invoke x.py
manually, which propagates BOOTSTRAP_PYTHON into the bootstrap
environment. But building LLVM will abort with error messages about not
being able to find Python, and instructions to set PYTHON_EXECUTABLE,
because nothing is done with BOOTSTRAP_PYTHON when invoking cmake.
Setting build.python in config.toml had no effect in this scenario,
either
To fix this, let's provide PYTHON_EXECUTABLE when invoking cmake; for
the "normal" case of Python in PATH, this doesn't alter any behavior.
For more unusual cases, however, this ensures cmake finds Python
properly. (This change also ensures there are no differences between
what bootstrap is using, and what cmake uses, which may be useful for
consistency's sake.)
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`.
