With #65251 landed there's no need to build two LLVM backends and ship
them with rustc, every target we have now uses the same LLVM backend!
This removes the `src/llvm-emscripten` submodule and additionally
removes all support from rustbuild for building the emscripten LLVM
backend. Multiple codegen backend support is left in place for now, and
this is intended to be an easy 10-15 minute win on CI times by avoiding
having to build LLVM twice.
- Compatible with Emscripten 1.38.46-upstream or later upstream.
- Refactors the Emscripten target spec to share code with other wasm
targets.
- Replaces the old incorrect wasm32 C call ABI with the correct one,
preserving the old one as wasm32_bindgen_compat for wasm-bindgen
compatibility.
- Updates the varargs ABI used by Emscripten and deletes the old one.
- Removes the obsolete wasm32-experimental-emscripten target.
- Uses EMCC_CFLAGS on CI to avoid the timeout problems with #63649.
- Refactors the Emscripten target spec to share code with other wasm
targets.
- Replaces the incorrect wasm32 C call ABI with the old asmjs
version, which is correct for both wasm32 and JS.
- Updates the varargs ABI used by Emscripten and deletes the old one.
- Removes the obsolete wasm32-experimental-emscripten target.
- Temporarily makes Emscripten targets use panic=abort by default
because supporting unwinding will require an LLVM patch.
This commit removes the `wasm_syscall` feature from the
wasm32-unknown-unknown build of the standard library. This feature was
originally intended to allow an opt-in way to interact with the
operating system in a posix-like way but it was never stabilized.
Nowadays with the advent of the `wasm32-wasi` target that should
entirely replace the intentions of the `wasm_syscall` feature.
This commit moves RISC-V from the experimental LLVM targets to the
regular LLVM targets. RISC-V was made non-experimental in
https://reviews.llvm.org/rL366399
I have also sorted the list of LLVM targets, and changed the code
around setting llvm_exp_targets (and its default) to match the code
setting llvm_targets (and its default), ensuring future changes to
the defaults, as LLVM targets become stable, affect as few places as
possible.
This renames wasm32-unknown-wasi to wasm32-wasi, omitting the vendor
component. This follows aarch64-linux-android, x86_64-fuchsia, and others in
omitting the vendor field, which has the advantage of aligning with the
[multiarch tuple](https://wiki.debian.org/Multiarch/Tuples), and of being
less noisy.
This commit adds a new wasm32-based target distributed through rustup,
supported in the standard library, and implemented in the compiler. The
`wasm32-unknown-wasi` target is intended to be a WebAssembly target
which matches the [WASI proposal recently announced.][LINK]. In summary
the WASI target is an effort to define a standard set of syscalls for
WebAssembly modules, allowing WebAssembly modules to not only be
portable across architectures but also be portable across environments
implementing this standard set of system calls.
The wasi target in libstd is still somewhat bare bones. This PR does not
fill out the filesystem, networking, threads, etc. Instead it only
provides the most basic of integration with the wasi syscalls, enabling
features like:
* `Instant::now` and `SystemTime::now` work
* `env::args` is hooked up
* `env::vars` will look up environment variables
* `println!` will print to standard out
* `process::{exit, abort}` should be hooked up appropriately
None of these APIs can work natively on the `wasm32-unknown-unknown`
target, but with the assumption of the WASI set of syscalls we're able
to provide implementations of these syscalls that engines can implement.
Currently the primary engine implementing wasi is [wasmtime], but more
will surely emerge!
In terms of future development of libstd, I think this is something
we'll probably want to discuss. The purpose of the WASI target is to
provide a standardized set of syscalls, but it's *also* to provide a
standard C sysroot for compiling C/C++ programs. This means it's
intended that functions like `read` and `write` are implemented for this
target with a relatively standard definition and implementation. It's
unclear, therefore, how we want to expose file descriptors and how we'll
want to implement system primitives. For example should `std::fs::File`
have a libc-based file descriptor underneath it? The raw wasi file
descriptor? We'll see! Currently these details are all intentionally
hidden and things we can change over time.
A `WasiFd` sample struct was added to the standard library as part of
this commit, but it's not currently used. It shows how all the wasi
syscalls could be ergonomically bound in Rust, and they offer a possible
implementation of primitives like `std::fs::File` if we bind wasi file
descriptors exactly.
Apart from the standard library, there's also the matter of how this
target is integrated with respect to its C standard library. The
reference sysroot, for example, provides managment of standard unix file
descriptors and also standard APIs like `open` (as opposed to the
relative `openat` inspiration for the wasi ssycalls). Currently the
standard library relies on the C sysroot symbols for operations such as
environment management, process exit, and `read`/`write` of stdio fds.
We want these operations in Rust to be interoperable with C if they're
used in the same process. Put another way, if Rust and C are linked into
the same WebAssembly binary they should work together, but that requires
that the same C standard library is used.
We also, however, want the `wasm32-unknown-wasi` target to be
usable-by-default with the Rust compiler without requiring a separate
toolchain to get downloaded and configured. With that in mind, there's
two modes of operation for the `wasm32-unknown-wasi` target:
1. By default the C standard library is statically provided inside of
`liblibc.rlib` distributed as part of the sysroot. This means that
you can `rustc foo.wasm --target wasm32-unknown-unknown` and you're
good to go, a fully workable wasi binary pops out. This is
incompatible with linking in C code, however, which may be compiled
against a different sysroot than the Rust code was previously
compiled against. In this mode the default of `rust-lld` is used to
link binaries.
2. For linking with C code, the `-C target-feature=-crt-static` flag
needs to be passed. This takes inspiration from the musl target for
this flag, but the idea is that you're no longer using the provided
static C runtime, but rather one will be provided externally. This
flag is intended to also get coupled with an external `clang`
compiler configured with its own sysroot. Therefore you'll typically
use this flag with `-C linker=/path/to/clang-script-wrapper`. Using
this mode the Rust code will continue to reference standard C
symbols, but the definition will be pulled in by the linker configured.
Alright so that's all the current state of this PR. I suspect we'll
definitely want to discuss this before landing of course! This PR is
coupled with libc changes as well which I'll be posting shortly.
[LINK]:
[wasmtime]:
look for python2 symlinks before bootstrap python
Before this commit, if you're running x.py directly on a system where
`python` is symlinked to Python 3, then the `python` config option will
default to a Python 3 interpreter. This causes debuginfo tests to fail
with an opaque error message, since they have a hard requirement on
Python 2.
This commit modifies the Python probe behavior to look for python2.7 and
python2 *before* using the interpreter used to execute `x.py`.
JSBackend is implied when building the emscripten backend, and not available for the standard llvm backend. This commit also puts the example config in sync with the defaults in src/bootstrap/native.rs
Before this commit, if you're running x.py directly on a system where
`python` is symlinked to Python 3, then the `python` config option will
default to a Python 3 interpreter. This causes debuginfo tests to fail
with an opaque error message, since they have a hard requirement on
Python 2.
This commit modifies the Python probe behavior to look for python2.7 and
python2 *before* using the interpreter used to execute `x.py`.
We'll use this as a temporary measure to get an LLVM update landed, but
we'll have to go through and update images later to make sure they've
got the right toolchains.
compiletest: Support opt-in Clang-based run-make tests and use them for testing xLTO.
Some cross-language run-make tests need a Clang compiler that matches the LLVM version of `rustc`. Since such a compiler usually isn't available these tests (marked with the `needs-matching-clang`
directive) are ignored by default.
For some CI jobs we do need these tests to run unconditionally though. In order to support this a `--force-clang-based-tests` flag is added to compiletest. If this flag is specified, `compiletest` will fail if it can't detect an appropriate version of Clang.
@rust-lang/infra The PR doesn't yet enable the tests yet. Do you have any recommendation for which jobs to enable them?
cc #57438
r? @alexcrichton
Provide the option to use libc++ even on all platforms
This is the default on platforms which use libc++ as the default C++
library but this option allows using libc++ on others as well.
The run-pass test suite currently takes 30 minutes on Windows, and
that appears to be roughly split between two 15 minute runs of the test
suite: one without NLL and one with NLL. In discussion on Discord the
platform coverage of the NLL compare mode may not necessarily be worth
it, so this commit removes the NLL compare mode from tests by default,
and then reenables it on only one builder.
This commit adds opt-in support to the compiler to link to `jemalloc` in
the compiler. When activated the compiler will depend on `jemalloc-sys`,
instruct jemalloc to unprefix its symbols, and then link to it. The
feature is activated by default on Linux/OSX compilers for x86_64/i686
platforms, and it's not enabled anywhere else for now. We may be able to
opt-in other platforms in the future! Also note that the opt-in only
happens on CI, it's otherwise unconditionally turned off by default.
Closes#36963
This commit removes all jemalloc related submodules, configuration, etc,
from the bootstrap, from the standard library, and from the compiler.
This will be followed up with a change to use jemalloc specifically as
part of rustc on blessed platforms.
In addition to to updating Cargo's submodule and Cargo's dependencies,
this also updates Cargo's build to build OpenSSL statically into Cargo
as well as libcurl unconditionally. This removes OpenSSL build logic
from the bootstrap code, and otherwise requests that even on OSX we
build curl statically.
This patch adds a few improvements to how the build system finds
LLVM's FileCheck program.
* On Fedora, the system LLVM installs FileCheck in the "llvm"
subdirectory of the LLVM libdir. This patch teaches the build
system to look there.
* This adds a configure option to specify which llvm-config executable
to use. This is handy on systems that can parallel install multiple
versions of LLVM; for example I can now:
./configure --llvm-config=/bin/llvm-config-5.0-64
... to build against LLVM 5, rather than whatever the default
llvm-config might be.
* Finally, this adds a configure- and config.toml- option to set the
path to FileCheck. This is handy when building against an LLVM
where FileCheck was not installed. This happens on compatibility
installs of LLVM on Fedora.
Add rustc SHA to released DWARF debuginfo
This commit updates the debuginfo that is encoded in all of our released
artifacts by default. Currently it has paths like `/checkout/src/...` but these
are a little inconsistent and have changed over time. This commit instead
attempts to actually define the file paths in our debuginfo to be consistent
between releases.
All debuginfo paths are now intended to be `/rustc/$sha` where `$sha` is the git
sha of the released compiler. Sub-paths are all paths into the git repo at that
`$sha`.
This commit updates the debuginfo that is encoded in all of our released
artifacts by default. Currently it has paths like `/checkout/src/...` but these
are a little inconsistent and have changed over time. This commit instead
attempts to actually define the file paths in our debuginfo to be consistent
between releases.
All debuginfo paths are now intended to be `/rustc/$sha` where `$sha` is the git
sha of the released compiler. Sub-paths are all paths into the git repo at that
`$sha`.
This optionally adds lldb (and clang, which it needs) to the build.
Because rust uses LLVM 7, and because clang 7 is not yet released, a
recent git master version of clang is used.
The lldb that is used includes the Rust plugin.
lldb is only built when asked for, or when doing a nightly build on
macOS. Only macOS is done for now due to difficulties with the Python
dependency.
Disable LLVM verification by default
Currently -Z no-verify only controls IR verification prior to LLVM codegen, while verification is performed unconditionally both before and after linking with (Thin)LTO.
Also wondering what the sentiment is on disabling verification by default (and e.g. only enabling it on ALT builds with assertions). This does not seem terribly useful outside of rustc development and it does seem to show up in profiles (at something like 3%).
**EDIT:** A table showing the various configurations and what is enabled when.
| Configuration | Dynamic verification performed | LLVM static assertions compiled in |
| --- | --- | --- |
| alt builds | | yes |
| nightly builds | | no |
| stable builds | | no |
| CI builds | | |
| dev builds in a checkout | | |
ship LLVM tools with the toolchain
this PR adds llvm-{nm,objcopy,objdump,size} to the rustc sysroot (right next to LLD)
this slightly increases the size of the rustc component. I measured these numbers on x86_64 Linux:
- rustc-1.27.0-dev-x86_64-unknown-linux-gnu.tar.gz 180M -> 193M (+7%)
- rustc-1.27.0-dev-x86_64-unknown-linux-gnu.tar.xz 129M -> 137M (+6%)
r? @alexcrichton
cc #49584
Currently on CI we predominately compile LLVM with the default system compiler
which means gcc on Linux, some version of Clang on OSX, MSVC on Windows, and
gcc on MinGW. This commit switches Linux, OSX, and Windows to all use Clang
6.0.0 to build LLVM (aka the C/C++ compiler as part of the bootstrap). This
looks to generate faster code according to #49879 which translates to a faster
rustc (as LLVM internally is faster)
The major changes here were to the containers that build Linux releases,
basically adding a new step that uses the previous gcc 4.8 compiler to compile
the next Clang 6.0.0 compiler. Otherwise the OSX and Windows scripts have been
updated to download precompiled versions of Clang 6 and configure the build to
use them.
Note that `cc` was updated here to fix using `clang-cl` with `cc-rs` on MSVC, as
well as an update to `sccache` on Windows which was needed to correctly work
with `clang-cl`. Finally the MinGW compiler is entirely left out here
intentionally as it's currently thought that Clang can't generate C++ code for
MinGW and we need to use gcc, but this should be verified eventually.
Debugging information for the extended tools is currently disabled for
concerns about the size. This patch adds `--enable-debuginfo-tools` to
let one opt into having that debuginfo.
This is useful for debugging the tools in distro packages. We always
strip debuginfo into separate packages anyway, so the extra size is not
a concern in regular use.
ci: Print out how long each step takes on CI
This commit updates CI configuration to inform rustbuild that it should print
out how long each step takes on CI. This'll hopefully allow us to track the
duration of steps over time and follow regressions a bit more closesly (as well
as have closer analysis of differences between two builds).
cc #48829
This commit updates CI configuration to inform rustbuild that it should print
out how long each step takes on CI. This'll hopefully allow us to track the
duration of steps over time and follow regressions a bit more closesly (as well
as have closer analysis of differences between two builds).
cc #48829
config.toml.example: thinlto bootstrap was removed
It was removed in ff227c4a2d so remove the option that no longer works (we did not notice because it was commented out by default).
This commit imports the LLD project from LLVM to serve as the default linker for
the `wasm32-unknown-unknown` target. The `binaryen` submoule is consequently
removed along with "binaryen linker" support in rustc.
Moving to LLD brings with it a number of benefits for wasm code:
* LLD is itself an actual linker, so there's no need to compile all wasm code
with LTO any more. As a result builds should be *much* speedier as LTO is no
longer forcibly enabled for all builds of the wasm target.
* LLD is quickly becoming an "official solution" for linking wasm code together.
This, I believe at least, is intended to be the main supported linker for
native code and wasm moving forward. Picking up support early on should help
ensure that we can help LLD identify bugs and otherwise prove that it works
great for all our use cases!
* Improvements to the wasm toolchain are currently primarily focused around LLVM
and LLD (from what I can tell at least), so it's in general much better to be
on this bandwagon for bugfixes and new features.
* Historical "hacks" like `wasm-gc` will soon no longer be necessary, LLD
will [natively implement][gc] `--gc-sections` (better than `wasm-gc`!) which
means a postprocessor is no longer needed to show off Rust's "small wasm
binary size".
LLD is added in a pretty standard way to rustc right now. A new rustbuild target
was defined for building LLD, and this is executed when a compiler's sysroot is
being assembled. LLD is compiled against the LLVM that we've got in tree, which
means we're currently on the `release_60` branch, but this may get upgraded in
the near future!
LLD is placed into rustc's sysroot in a `bin` directory. This is similar to
where `gcc.exe` can be found on Windows. This directory is automatically added
to `PATH` whenever rustc executes the linker, allowing us to define a `WasmLd`
linker which implements the interface that `wasm-ld`, LLD's frontend, expects.
Like Emscripten the LLD target is currently only enabled for Tier 1 platforms,
notably OSX/Windows/Linux, and will need to be installed manually for compiling
to wasm on other platforms. LLD is by default turned off in rustbuild, and
requires a `config.toml` option to be enabled to turn it on.
Finally the unstable `#![wasm_import_memory]` attribute was also removed as LLD
has a native option for controlling this.
[gc]: https://reviews.llvm.org/D42511
Customizable extended tools
This PR adds `build.tools` option to manage installation of extended rust tools.
By default it doesn't change installation. All tools are built and `rls` and `rustfmt` allowed to fail installation.
If some set of tools chosen only those tools are built and installed without any fails allowed.
It solves some slotting issues with extended build enabled: https://bugs.gentoo.org/show_bug.cgi?id=645498
Dist builds should always be as fast as we can make them, and since
those run on CI we don't care quite as much for the build being somewhat
slower. As such, we don't automatically enable ThinLTO on builds for the
dist builders.
This commit introduces a separately compiled backend for Emscripten, avoiding
compiling the `JSBackend` target in the main LLVM codegen backend. This builds
on the foundation provided by #47671 to create a new codegen backend dedicated
solely to Emscripten, removing the `JSBackend` of the main codegen backend in
the process.
A new field was added to each target for this commit which specifies the backend
to use for translation, the default being `llvm` which is the main backend that
we use. The Emscripten targets specify an `emscripten` backend instead of the
main `llvm` one.
There's a whole bunch of consequences of this change, but I'll try to enumerate
them here:
* A *second* LLVM submodule was added in this commit. The main LLVM submodule
will soon start to drift from the Emscripten submodule, but currently they're
both at the same revision.
* Logic was added to rustbuild to *not* build the Emscripten backend by default.
This is gated behind a `--enable-emscripten` flag to the configure script. By
default users should neither check out the emscripten submodule nor compile
it.
* The `init_repo.sh` script was updated to fetch the Emscripten submodule from
GitHub the same way we do the main LLVM submodule (a tarball fetch).
* The Emscripten backend, turned off by default, is still turned on for a number
of targets on CI. We'll only be shipping an Emscripten backend with Tier 1
platforms, though. All cross-compiled platforms will not be receiving an
Emscripten backend yet.
This commit means that when you download the `rustc` package in Rustup for Tier
1 platforms you'll be receiving two trans backends, one for Emscripten and one
that's the general LLVM backend. If you never compile for Emscripten you'll
never use the Emscripten backend, so we may update this one day to only download
the Emscripten backend when you add the Emscripten target. For now though it's
just an extra 10MB gzip'd.
Closes#46819
This commit alters how we compile LLVM by default enabling the WebAssembly
backend. This then also adds the wasm32-unknown-unknown target to get compiled
on the `cross` builder and distributed through rustup. Tests are not yet enabled
for this target but that should hopefully be coming soon!
... specifically `datadir`, `infodir`, and `localstatedir`. These were
already accepted by `configure.py`, but it didn't have any place to put
the values.
While the `config.toml.example` comments say "we automatically check the
version by default," we actually didn't. That check was badly out of
date, only allowing 3.5, 3.6, or 3.7. This it now updated to the new
3.9 minimum requirement, and truly enabled by default.
This commit rewrites our ancient `./configure` script from shell into Python.
The impetus for this change is to remove `config.mk` which is just a vestige of
the old makefile build system at this point. Instead all configuration is now
solely done through `config.toml`.
The python script allows us to more flexibly program (aka we can use loops
easily) and create a `config.toml` which is based off `config.toml.example`.
This way we can preserve comments and munge various values as we see fit.
It is intended that the configure script here is a drop-in replacement for the
previous configure script, no functional change is intended. Also note that the
rationale for this is also because our build system requires Python, so having a
python script a bit earlier shouldn't cause too many problems.
Closes#40730
This controls the value of the crt-static feature used when building the
standard library for a target, as well as the compiler itself when that
target is the host.
Some users of the build system change the git sha on every build due to
utilizing git to push changes to a remote server. This allows them to
simply configure that away instead of depending on custom patches to
rustbuild.
