Add MIR Optimization Tests
I've starting working on the infrastructure for testing MIR optimizations.
The plan now is to have a set of test cases (written in Rust), compile them with -Z dump-mir, and check the MIR before and after each pass.
The compiler-rt build system has been a never ending cause of pain for Rust
unfortunately:
* The build system is very difficult to invoke and configure to only build
compiler-rt, especially across platforms.
* The standard build system doesn't actually do what we want, not working for
some of our platforms and requiring a significant number of patches on our end
which are difficult to apply when updating compiler-rt.
* Compiling compiler-rt requires LLVM to be compiled, which... is a big
dependency! This also means that over time compiler-rt is not guaranteed to
build against older versions of LLVM (or newer versions), and we often want to
work with multiple versions of LLVM simultaneously.
The makefiles and rustbuild already know how to compile C code, the code here is
far from the *only* C code we're compiling. This patch jettisons all logic to
work with compiler-rt's build system and just goes straight to the source. We
just list all files manually (copied from compiler-rt's
lib/builtins/CMakeLists.txt) and compile them into an archive.
It's likely that this means we'll fail to pick up new files when we upgrade
compiler-rt, but that seems like a much less significant cost to pay than what
we're currently paying.
cc #34400, first steps towards that
llvm, rt: build using the Ninja generator if available
The Ninja generator generally builds much faster than make. It may also
be used on Windows to have a vast speed improvement over the Visual
Studio generators.
Currently hidden behind an `--enable-ninja` flag because it does not
obey the top-level `-j` or `-l` flags given to `make`.
If local-rust is the same as the current version, then force a local-rebuild
In Debian, we would like the option to build/rebuild the current release from
*either* the current or previous stable release. So we use enable-local-rust
instead of enable-local-rebuild, and read the bootstrap key dynamically from
whatever is installed locally.
In general, it does not make much sense to allow enable-local-rust without also
setting the bootstrap key, since the build would fail otherwise.
(The way I detect "the bootstrap key of [the local] rustc installation" is a bit hacky, suggestions welcome.)
Soon the LLVM upgrade (#34743) will require an updated CMake installation, and
the easiest way to do this was to upgrade the Ubuntu version of the bots to
16.04. This in turn brings in a new MIPS compiler on the linux-cross builder,
which is now from the "official" ubuntu repositories. Unfortunately these
new compilers don't support compiling with the `-msoft-float` flag like we're
currently passing, causing compiles to fail.
This commit removes these flags as it's not clear *why* they're being passed, as
the mipsel targets also don't have it. At least if it's not supported by a
debian default compiler, perhaps it's not too relevant to support?
The Ninja generator generally builds much faster than make. It may also
be used on Windows to have a vast speed improvement over the Visual
Studio generators.
Currently hidden behind an `--enable-ninja` flag because it does not
obey the top-level `-j` or `-l` flags given to `make`.
mk: Request -march=i686 on i686 Linux
Apparently the gcc on our dist bot is so old and/or obscure that the default
`-m32` switch doesn't think it can generate i686 code (or something like that).
The compiler-rt build system probes for the `__i686__` define in GCC to compile
for an i686 (vs i386) target, so this was failing on the bots.
This tweaks instead to pass `-march=i686` on i686-unknown-linux-gnu to C code to
ensure that we're compiling for i686 instead of i386. This should hopefully not
actually have an impact other than maybe doing some random optimization it
wasn't able to do so before. In theory this isn't making the target less
compatible as all Rust code is already compiled for i686.
Hopefully closes#34572
Apparently the gcc on our dist bot is so old and/or obscure that the default
`-m32` switch doesn't think it can generate i686 code (or something like that).
The compiler-rt build system probes for the `__i686__` define in GCC to compile
for an i686 (vs i386) target, so this was failing on the bots.
This tweaks instead to pass `-march=i686` on i686-unknown-linux-gnu to C code to
ensure that we're compiling for i686 instead of i386. This should hopefully not
actually have an impact other than maybe doing some random optimization it
wasn't able to do so before. In theory this isn't making the target less
compatible as all Rust code is already compiled for i686.
Hopefully closes#34572
Currently if an LLVM build is interrupted *after* it creates the llvm-config
binary but before it's done it puts us in an inconsistent state where we think
LLVM is compiled but it's not actually. This tweaks our logic to only consider
LLVM done building once it's actually done building.
This should hopefully alleviate problems on the bots where if we interrupt at
the wrong time it doesn't corrupt the build directory.
Try to fix the nightlies
They look to be failing right after the CMake PR landed. I've diagnosed and confirmed the first issue fixed, the second is a bit of a shot in the dark to see if it fixes things.
* Implement the clean-llvm target for those cases where makefiles are being used
* Have all cross-compiled LLVMs depend on the **host** LLVM as they'll require
the llvm-tablegen executable from there
This PR refactors the 'errors' part of libsyntax into its own crate (librustc_errors). This is the first part of a few refactorings to simplify error reporting and potentially support more output formats (like a standardized JSON output and possibly an --explain mode that can work with the user's code), though this PR stands on its own and doesn't assume further changes.
As part of separating out the errors crate, I have also refactored the code position portion of codemap into its own crate (libsyntax_pos). While it's helpful to have the common code positions in a separate crate for the new errors crate, this may also enable further simplifications in the future.
mk: Fix bootstrapping cross-hosts on beta
The beta builds are currently failing, unfortunately, due to what is presumably
some odd behavior with our makefiles. The wrong bootstrap key is being used to
generate the stage1 cross-compiled libraries, which fails the build.
Interestingly enough if the targets are directly specified as part of the build
then it works just fine! Just a bare `make` fails...
Instead of trying to understand what's happening in the makefiles instead just
tweak how we configure the bootstrap key in a way that's more likely to work.
The beta builds are currently failing, unfortunately, due to what is presumably
some odd behavior with our makefiles. The wrong bootstrap key is being used to
generate the stage1 cross-compiled libraries, which fails the build.
Interestingly enough if the targets are directly specified as part of the build
then it works just fine! Just a bare `make` fails...
Instead of trying to understand what's happening in the makefiles instead just
tweak how we configure the bootstrap key in a way that's more likely to work.
In Linux distributions, it is often necessary to rebuild packages for
cases like applying new patches or linking against new system libraries.
In this scenario, the rustc in the distro build environment may already
match the current release that we're trying to rebuild. Thus we don't
want to use the prior release's bootstrap key, nor `--cfg stage0` for
the prior unstable features.
The new `configure --enable-local-rebuild` option specifies that we are
rebuilding from the current release. The current bootstrap key is used
for the local rustc, and current stage1 features are also assumed.
This commit is an implementation of [RFC 1513] which allows applications to
alter the behavior of panics at compile time. A new compiler flag, `-C panic`,
is added and accepts the values `unwind` or `panic`, with the default being
`unwind`. This model affects how code is generated for the local crate, skipping
generation of landing pads with `-C panic=abort`.
[RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md
Panic implementations are then provided by crates tagged with
`#![panic_runtime]` and lazily required by crates with
`#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic
runtime must match the final product, and if the panic strategy is not `abort`
then the entire DAG must have the same panic strategy.
With the `-C panic=abort` strategy, users can expect a stable method to disable
generation of landing pads, improving optimization in niche scenarios,
decreasing compile time, and decreasing output binary size. With the `-C
panic=unwind` strategy users can expect the existing ability to isolate failure
in Rust code from the outside world.
Organizationally, this commit dismantles the `sys_common::unwind` module in
favor of some bits moving part of it to `libpanic_unwind` and the rest into the
`panicking` module in libstd. The custom panic runtime support is pretty similar
to the custom allocator support with the only major difference being how the
panic runtime is injected (takes the `-C panic` flag into account).
Add armv7-linux-androideabi target
This PR adds `armv7-linux-androideabi` target that matches `armeabi-v7a` Android ABI, ~~downscales `arm-linux-androideabi` target to match `armeabi` Android ABI~~ (TBD later if needed).
This should allow us to get the best performance from every [Android ABI level](http://developer.android.com/ndk/guides/abis.html).
Currently existing target `arm-linux-androideabi` started gaining features out of the supported range of [android `armeabi`](http://developer.android.com/ndk/guides/abis.html). While android compiler does not use a different target for later supported `armv7` architecture, it has distinct ABI name `armeabi-v7a`. We decided to add rust target `armv7-linux-androideabi` to match it.
Note that `NEON`, `VFPv3-D32`, and `ThumbEE` instruction sets are not added, because not all android devices are guaranteed to support all or some of these, and [their availability should be checked at runtime](http://developer.android.com/ndk/guides/abis.html#v7a).
~~This reduces performance of existing `arm-linux-androideabi` and may make it _much_ slower (we are talking more than order of magnitude in some random ad-hoc fp benchmark that I did).~~
Part of #33278.
make dist: specify the archive file as stdout
If the `-f` option isn't given, GNU tar will use environment variable
`TAPE` first, and next use the compiled-in default, which isn't
necessary `stdout` (it is the tape device `/dev/rst0` under OpenBSD for
example).
Implement constant support in MIR.
All of the intended features in `trans::consts` are now supported by `mir::constant`.
The implementation is considered a temporary measure until `miri` replaces it.
A `-Z orbit` bootstrap build will only translate LLVM IR from AST for `#[rustc_no_mir]` functions.
Furthermore, almost all checks of constant expressions have been moved to MIR.
In non-`const` functions, trees of temporaries are promoted, as per RFC 1414 (rvalue promotion).
Promotion before MIR borrowck would allow reasoning about promoted values' lifetimes.
The improved checking comes at the cost of four `[breaking-change]`s:
* repeat counts must contain a constant expression, e.g.:
`let arr = [0; { println!("foo"); 5 }];` used to be allowed (it behaved like `let arr = [0; 5];`)
* dereference of a reference to a `static` cannot be used in another `static`, e.g.:
`static X: [u8; 1] = [1]; static Y: u8 = (&X)[0];` was unintentionally allowed before
* the type of a `static` *must* be `Sync`, irrespective of the initializer, e.g.
`static FOO: *const T = &BAR;` worked as `&T` is `Sync`, but it shouldn't because `*const T` isn't
* a `static` cannot wrap `UnsafeCell` around a type that *may* need drop, e.g.
`static X: MakeSync<UnsafeCell<Option<String>>> = MakeSync(UnsafeCell::new(None));`
was previously allowed based on the fact `None` alone doesn't need drop, but in `UnsafeCell`
it can be later changed to `Some(String)` which *does* need dropping
The drop restrictions are relaxed by RFC 1440 (#33156), which is implemented, but feature-gated.
However, creating `UnsafeCell` from constants is unstable, so users can just enable the feature gate.
mk: Fix building with --enable-ccache
We will no longer use `ccache` in the makefiles for our local dependencies like
miniz, but they're so small anyway it doesn't really matter.
Closes#33285
Move auxiliary directories to live with the tests
This is a step for enabling testing of cross-crate incremental compilation. The idea is that instead of having a central auxiliary directory, when you have a `// aux-build:foo.rs` annotation in the test `run-pass/bar.rs`, it will look in (e.g.) `run-pass/aux/foo.rs`. In general, it looks for an `aux` directory in the same directory as the test. We also ignore the `aux` directories when enumerating the set of tests.
As part of this PR, also refactor `runtest.rs` to use methods on a context, which means we can stop passing around context everywhere.
r? @alexcrichton
Looks like the real bug on nightlies is that the `llvm-pass` run-make test is
not actually getting the value of `LLVM_CXXFLAGS` correct. Namely, it's blank!
Now the only change #33093 which actually affected this is that the argument
`$(LLVM_CXXFLAGS_$(2))` was moved up from a makefile rule into the definition of
a variable. Sounds innocuous?
Turns out the variable this was moved into is defined with `:=`, which means
that it's not recursively expanded, which basically means that it's expanded
immediately. Unfortunately part of this expansion involves running
`llvm-config`, which doesn't exist at the start of distcheck build!
This didn't show up on the bots because they run `make` *then* `make check`, and
the first step builds llvm-config so the next time `make` is loaded everything
is available. The distcheck bots, however, run just a plain `distcheck` so
`make` doesn't exist ahead of time. You can see this in action where the
distcheck bots start out with a bunch of "llvm-config not found" error messages.
This commit just changes a few variables to be defined with `=` which
essentially means they're lazily expanded. I did not run a full distcheck
locally, but this makes the initial "llvm-config not found" error messages go
away so I suspect that this is the fix.
Closes#33379
We will no longer use `ccache` in the makefiles for our local dependencies like
miniz, but they're so small anyway it doesn't really matter.
Closes#33285
If the `-f` option isn't given, GNU tar will use environment variable
`TAPE` first, and next use the compiled-in default, which isn't
necessary `stdout` (it is the tape device `/dev/rst0` under OpenBSD for
example).
This changes the CFLAGS and related variables passed to compiletest to be passed
for the target, not the host, so we can correctly test 32-bit cross compiles on
64-bit host machines.
Hopefuly fixes#33379
test: Move run-make tests into compiletest
Forcing them to be embedded in makefiles precludes being able to run them in
rustbuild, and adding them to compiletest gives us a great way to leverage
future enhancements to our "all encompassing test suite runner" as well as just
moving more things into Rust.
All tests are still Makefile-based in the sense that they rely on `make` being
available to run them, but there's no longer any Makefile-trickery to run them
and rustbuild can now run them out of the box as well.
Forcing them to be embedded in makefiles precludes being able to run them in
rustbuild, and adding them to compiletest gives us a great way to leverage
future enhancements to our "all encompassing test suite runner" as well as just
moving more things into Rust.
All tests are still Makefile-based in the sense that they rely on `make` being
available to run them, but there's no longer any Makefile-trickery to run them
and rustbuild can now run them out of the box as well.
The `--android-cross-path` has been deprecated for some time now, we should use
`CFG_ARM_LINUX_ANDROIDEABI_NDK` instead.
Ideally this would use the right triple, but we're only testing ARM for now.
Sanity check Python on OSX for LLDB tests
Two primary changes:
* Don't get past the configure stage if `python` isn't coming from `/usr/bin`
* Call `debugger.Terminate()` to prevent segfaults on newer versions of LLDB.
Closes#32994
This uncovered a lot of bugs in compiletest and also some shortcomings
of our existing JSON output. We had to add information to the JSON
output, such as suggested text and macro backtraces. We also had to fix
various bugs in the existing tests.
Joint work with jntrnr.
Compute `target_feature` from LLVM
This is a work-in-progress fix for #31662.
The logic that computes the target features from the command line has been replaced with queries to the `TargetMachine`.
This commit removes all infrastructure from the repository for our so-called
snapshots to instead bootstrap the compiler from stable releases. Bootstrapping
from a previously stable release is a long-desired feature of distros because
they're not fans of downloading binary stage0 blobs from us. Additionally, this
makes our own CI easier as we can decommission all of the snapshot builders and
start having a regular cadence to when we update the stage0 compiler.
A new `src/etc/get-stage0.py` script was added which shares some code with
`src/bootstrap/bootstrap.py` to read a new file, `src/stage0.txt`, which lists
the current stage0 compiler as well as cargo that we bootstrap from. This script
will download the relevant `rustc` package an unpack it into `$target/stage0` as
we do today.
One problem of bootstrapping from stable releases is that we're not able to
compile unstable code (e.g. all the `#![feature]` directives in libcore/libstd).
To overcome this we employ two strategies:
* The bootstrap key of the previous compiler is hardcoded into `src/stage0.txt`
(enabled as a result of #32731) and exported by the build system. This enables
nightly features in the compiler we download.
* The standard library and compiler are pinned to a specific stage0, which
doesn't change, so we're guaranteed that we'll continue compiling as we start
from a known fixed source.
The process for making a release will also need to be tweaked now to continue to
cadence of bootstrapping from the previous release. This process looks like:
1. Merge `beta` to `stable`
2. Produce a new stable compiler.
3. Change `master` to bootstrap from this new stable compiler.
4. Merge `master` to `beta`
5. Produce a new beta compiler
6. Change `master` to bootstrap from this new beta compiler.
Step 3 above should involve very few changes as `master` was previously
bootstrapping from `beta` which is the same as `stable` at that point in time.
Step 6, however, is where we benefit from removing lots of `#[cfg(stage0)]` and
get to use new features. This also shouldn't slow the release too much as steps
1-5 requires little work other than waiting and step 6 just needs to happen at
some point during a release cycle, it's not time sensitive.
Closes#29555Closes#29557
This commit adds support in rustbuild for running all of the compiletest test
suites as part of `make check`. The `compiletest` program was moved to
`src/tools` (like `rustbook` and others) and is now just compiled like any other
old tool. Each test suite has a pretty standard set of dependencies and just
tweaks various parameters to the final compiletest executable.
Note that full support is lacking in terms of:
* Once a test suite has passed, that's not remembered. When a test suite is
requested to be run, it's always run.
* The arguments to compiletest probably don't work for every possible
combination of platforms and testing environments just yet. There will likely
need to be future updates to tweak various pieces here and there.
* Cross compiled test suites probably don't work just yet, support for that will
come in a follow-up patch.
This verifies that the crates listed in the `[dependencies]` section of
`Cargo.toml` are a subset of the crates listed in `lib.rs` for our in-tree
crates. This should help ensure that when we refactor crates over time we keep
these dependency lists in sync.
This commit rewrites all of the tidy checks we have, namely:
* featureck
* errorck
* tidy
* binaries
into Rust under a new `tidy` tool inside of the `src/tools` directory. This at
the same time deletes all the corresponding Python tidy checks so we can be sure
to only have one source of truth for all the tidy checks.
cc #31590
mk: Hardcode the bootstrap key for each release
Starting with the 1.10.0 release we would like to bootstrap all compilers from
the previous stable release. For example the 1.10.0 compiler should bootstrap
from the literal 1.9.0 release artifacts. To do this, however, we need a way to
enable unstable features temporarily in a stable compiler (as the released
compiler is stable), but it turns out we already have a way to do that!
At compile time the configure script selects a `CFG_BOOTSTRAP_KEY` variable
value and then exports it into the makefiles. If the `RUSTC_BOOTSTRAP_KEY`
environment variable is set to this value, then the compiler is allowed to
"cheat" and use unstable features.
This method of choosing the bootstrap key, however, is problematic for the
intention of bootstrapping from the previous release. Each time a 1.9.0 compiler
is created, a new bootstrap key will be selected. That means that the 1.10.0
compiler will only compile from *our* literal release artifacts. Instead
distributions would like to bootstrap from their own compilers, so instead we
simply hardcode the bootstrap key for each release.
This patch uses the same `CFG_FILENAME_EXTRA` value (a hash of the release
string) as the bootstrap key. Consequently all 1.9.0 compilers, no matter where
they are compiled, will have the same bootstrap key. Additionally we won't need
to keep updating this as it'll be based on the release number anyway.
Once the 1.9.0 beta has been created, we can update the 1.10.0 nightly sources
(the `master` branch at that time) to bootstrap from that release using this
hard-coded bootstrap key. We will likely just hardcode into the makefiles what
the previous bootstrap key was and we'll change that whenever the stage0
compiler is updated.
Starting with the 1.10.0 release we would like to bootstrap all compilers from
the previous stable release. For example the 1.10.0 compiler should bootstrap
from the literal 1.9.0 release artifacts. To do this, however, we need a way to
enable unstable features temporarily in a stable compiler (as the released
compiler is stable), but it turns out we already have a way to do that!
At compile time the configure script selects a `CFG_BOOTSTRAP_KEY` variable
value and then exports it into the makefiles. If the `RUSTC_BOOTSTRAP_KEY`
environment variable is set to this value, then the compiler is allowed to
"cheat" and use unstable features.
This method of choosing the bootstrap key, however, is problematic for the
intention of bootstrapping from the previous release. Each time a 1.9.0 compiler
is created, a new bootstrap key will be selected. That means that the 1.10.0
compiler will only compile from *our* literal release artifacts. Instead
distributions would like to bootstrap from their own compilers, so instead we
simply hardcode the bootstrap key for each release.
This patch uses the same `CFG_FILENAME_EXTRA` value (a hash of the release
string) as the bootstrap key. Consequently all 1.9.0 compilers, no matter where
they are compiled, will have the same bootstrap key. Additionally we won't need
to keep updating this as it'll be based on the release number anyway.
Once the 1.9.0 beta has been created, we can update the 1.10.0 nightly sources
(the `master` branch at that time) to bootstrap from that release using this
hard-coded bootstrap key. We will likely just hardcode into the makefiles what
the previous bootstrap key was and we'll change that whenever the stage0
compiler is updated.
Our `codegen` test suite requires the LLVM `FileCheck` utility but unfortunately
this isn't always available in all custom LLVM roots (e.g. those specified via
`--llvm-root`). This commit adds a `./configure` option called
`--disable-codegen-tests` which will manually disable running these tests. In
the case that this option is passed we can forgo the need for the `FileCheck`
executable. Note that we still require `FileCheck` by default as we will attempt
to run these tests.
Closes#28667
mk: A few build fixes for i586-pc-windows-msvc
Detect the triple in the configure script for probing MSVC shenanigans and also
be sure to use `llvm-config` from the build host and not the target when
configuring compiler-rt.
mk: Fix cross-host builds
The change in b20e748 had the unintended consequence of breaking cross-host
builds as we apparently relied on the incorrect definition of this variable in
the makefiles. That change, however, was required to get tests passing so we
couldn't just revert it.
This commit fixes the underlying bug by leaving the "more correct" definition of
`LD_LIBRARY_PATH_ENV_TARGETDIR` (also fixing it with a hardcoded reference to
`CFG_BUILD`) and updating the `RPATH_VAR` definition below. Turned out we
already had special-casing logic for passing `--cfg stage1` during the
well-we-print-this-as-stage0 build of a cross-host. That logic was just updated
to pull from a different variable as opposed to relying on the definition of
that variable to accommodate this.
Closes#32568
Detect the triple in the configure script for probing MSVC shenanigans and also
be sure to use `llvm-config` from the build host and not the target when
configuring compiler-rt.
The change in b20e748 had the unintended consequence of breaking cross-host
builds as we apparently relied on the incorrect definition of this variable in
the makefiles. That change, however, was required to get tests passing so we
couldn't just revert it.
This commit fixes the underlying bug by leaving the "more correct" definition of
`LD_LIBRARY_PATH_ENV_TARGETDIR` (also fixing it with a hardcoded reference to
`CFG_BUILD`) and updating the `RPATH_VAR` definition below. Turned out we
already had special-casing logic for passing `--cfg stage1` during the
well-we-print-this-as-stage0 build of a cross-host. That logic was just updated
to pull from a different variable as opposed to relying on the definition of
that variable to accommodate this.
Closes#32568
This should re-enable all external builds of crates with the same name. Right
now Cargo doesn't pass `-C metadata` for the top-level library being compiled,
so if that library is called `libc`, for example, then it won't be able to link
to the standard library which *also* has a `libc` library compiled without `-C
metadata`. This can result in naming conflicts which need to be resolved.
By passing `-C metadata` to the in-tree crates we ship it should add some extra
salt to all symbol names to ensure that they don't collide.
emit (via debug!) scary message from `fn borrowck_mir` until basic
prototype is in place.
Gather children of move paths and set their kill bits in
dataflow. (Each node has a link to the child that is first among its
siblings.)
Hooked in libgraphviz based rendering, including of borrowck dataflow
state.
doing this well required some refactoring of the code, so I cleaned it
up more generally (adding comments to explain what its trying to do
and how it is doing it).
Update: this newer version addresses most review comments (at least
the ones that were largely mechanical changes), but I left the more
interesting revisions to separate followup commits (in this same PR).
typestrong const integers
~~It would be great if someone could run crater on this PR, as this has a high danger of breaking valid code~~ Crater ran. Good to go.
----
So this PR does a few things:
1. ~~const eval array values when const evaluating an array expression~~
2. ~~const eval repeat value when const evaluating a repeat expression~~
3. ~~const eval all struct and tuple fields when evaluating a struct/tuple expression~~
4. remove the `ConstVal::Int` and `ConstVal::Uint` variants and replace them with a single enum (`ConstInt`) which has variants for all integral types
* `usize`/`isize` are also enums with variants for 32 and 64 bit. At creation and various usage steps there are assertions in place checking if the target bitwidth matches with the chosen enum variant
5. enum discriminants (`ty::Disr`) are now `ConstInt`
6. trans has its own `Disr` type now (newtype around `u64`)
This obviously can't be done without breaking changes (the ones that are noticable in stable)
We could probably write lints that find those situations and error on it for a cycle or two. But then again, those situations are rare and really bugs imo anyway:
```rust
let v10 = 10 as i8;
let v4 = 4 as isize;
assert_eq!(v10 << v4 as usize, 160 as i8);
```
stops compiling because 160 is not a valid i8
```rust
struct S<T, S> {
a: T,
b: u8,
c: S
}
let s = S { a: 0xff_ff_ff_ffu32, b: 1, c: 0xaa_aa_aa_aa as i32 };
```
stops compiling because `0xaa_aa_aa_aa` is not a valid i32
----
cc @eddyb @pnkfelix
related: https://github.com/rust-lang/rfcs/issues/1071
Add a link validator to rustbuild
This commit was originally targeted at just adding a link checking script to the rustbuild system. This ended up snowballing a bit to extend rustbuild to be amenable to various tools we have as part of the build system in general.
There's a new `src/tools` directory which has a number of scripts/programs that are purely intended to be used as part of the build system and CI of this repository. This is currently inhabited by rustbook, the error index generator, and a new linkchecker script added as part of this PR. I suspect that more tools like compiletest, tidy scripts, snapshot scripts, etc will migrate their way into this directory over time.
The commit which adds the error index generator shows the steps necessary to add new tools to the build system, namely:
1. New steps are defined for building the tool and running the tool
2. The dependencies are configured
3. The steps are implemented
In terms of the link checker, these commits do a few things:
* A new `src/tools/linkchecker` script is added. This will read an entire documentation tree looking for broken relative links (HTTP links aren't followed yet).
* A large number of broken links throughout the documentation were fixed. Many of these were just broken when viewed from core as opposed to std, but were easily fixed.
* A few rustdoc bugs here and there were fixed
rustc: Add an i586-pc-windows-msvc target
Similarly to #31629 where an i586-unknown-linux-gnu target was added, there is
sometimes a desire to compile for x86 Windows as well where SSE2 is disabled.
This commit mirrors the i586-unknown-linux-gnu target and simply adds a variant
for Windows as well.
This is motivated by a recent [Gecko bug][ff] where crashes were seen on 32-bit
Windows due to users having CPUs that don't support SSE2 instructions. It was
requested that we could have non-SSE2 builds of the standard library available
so they could continue to use vanilla releases and nightlies.
[ff]: https://bugzilla.mozilla.org/show_bug.cgi?id=1253202
mk: Distribute fewer TARGET_CRATES
Right now everything in TARGET_CRATES is built by default for all non-fulldeps
tests and is distributed by default for all target standard library packages.
Currenly this includes a number of unstable crates which are rarely used such as
`graphviz` and `rbml`>
This commit trims down the set of `TARGET_CRATES`, moves a number of tests to
`*-fulldeps` as a result, and trims down the dependencies of libtest so we can
distribute fewer crates in the `rust-std` packages.
