When `capture_disjoint_fields` is not enabled, checking if the root variable
binding is mutable would suffice.
However with the feature enabled, the captured place might be mutable
because it dereferences a mutable reference.
This PR computes the mutability of each capture after capture analysis
in rustc_typeck. We store this in `ty::CapturedPlace` and then use
`ty::CapturedPlace::mutability` in mir_build and borrow_check.
- No Derefs in move closure, this will result in value behind a reference getting moved.
- No projections are applied to raw pointers, since these require unsafe blocks. We capture
them completely.
Motivations for these are recorded here: https://hackmd.io/71qq-IOpTNqzMkPpAI1dVg?view
On Windows, libstd uses GetProcAddress to locate some DLL imports, so
that libstd can run on older versions of Windows. If a given DLL import
is not present, then libstd uses other behavior (such as fallback
implementations).
This commit uses a feature of the Windows CRT to do these DLL imports
during module initialization, before main() (or DllMain()) is called.
This is the ideal time to resolve imports, because the module is
effectively single-threaded at that point; no other threads can
touch the data or code of the module that is being initialized.
This avoids several problems. First, it makes the cost of performing
the DLL import lookups deterministic. Right now, the DLL imports are
done on demand, which means that application threads _might_ have to
do the DLL import during some time-sensitive operation. This is a
small source of unpredictability. Since threads can race, it's even
possible to have more than one thread running the same redundant
DLL lookup.
This commit also removes using the heap to allocate strings, during
the DLL lookups.
This updates the dist-various-1 and dist-various-2 images to Ubuntu
20.04. This requires some adjustments:
* `DEBIAN_FRONTEND=noninteractive` required for apt install.
* `team-gcc-argm-embedded` PPA does not support focal. However,
we can simply use the distro-provided `gcc-arm-none-eabi`. Per
the comment, the PPA was only used to get a newer version.
* rumprun has to be updated to avoid a linker error.
* We need to build rumrun with `NOGCCERROR`, which disables use
of `-Werror` and allows building with a newer compiler.
* We need to install `libtinfo5`, which appears to be a dependency
of the clang used during the fuchsia build.
* We need to switch to `g++-8` rather than `g++-7`, as at least
`g++-7-arm-linux-gnueabi` is not available on focal.
* We need to upgrade to GCC 6.5 for the Solaris build, as GCC 6.4
does not support the newer libisl version.
Before, it could print this error if no toolchain was configured:
```
error: no default toolchain configured
error: backtrace:
error: stack backtrace:
0: error_chain::backtrace:👿:InternalBacktrace::new
1: rustup::config::Cfg::toolchain_for_dir
2: rustup_init::run_rustup_inner
3: rustup_init::main
4: std::rt::lang_start::{{closure}}
5: main
6: __libc_start_main
7: _start
```
Avoid memory allocation when removing dead blocks
Use `reachable_as_bitset` to reuse a bitset from the traversal rather
than allocating it seprately. Additionally check if there are any
unreachable blocks before proceeding.
Pre-canoncalize ExternLocation::ExactPaths
This stores pre-canacolized paths inside `ExternLocation::ExactPaths` so that we don't need to canoncalize them every time we want to compare them to source lib paths.
This is related to #81414.
This commit makes cfg(version) treat the nightlies
for version 1.n.0 as 1.n.0, even though that nightly
version might not have all stabilizations and features
of the released 1.n.0. This is done for greater
convenience for people who want to test a newly
stabilized feature on nightly.
For users who wish to pin nightlies, this commit adds
a -Z assume-incomplete-release option that they can
enable if there are any issues due to this change.
BTreeMap: prevent tree from ever being owned by non-root node
This introduces a new marker type, `Dying`, which is used to note trees which are in the process of deallocation. On such trees, some fields may be in an inconsistent state as we are deallocating the tree. Unfortunately, there's not a great way to express conditional unsafety, so the methods for traversal can cause UB if not invoked correctly, but not marked as such. This is not a regression from the previous state, but rather isolates the destructive methods to solely being called on the dying state.
Previously, the HTML output format was represented by both
`Some(OutputFormat::Html)` and `None` so there's no need to have an
optional. Instead, `OutputFormat::Html` is explicitly the default and we
no longer have a "tri-state enum".
Rollup of 10 pull requests
Successful merges:
- #79570 (rustc: Stabilize `-Zrun-dsymutil` as `-Csplit-debuginfo`)
- #79819 (Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` lint)
- #79991 (rustdoc: Render HRTB correctly for bare functions)
- #80215 (Use -target when linking binaries for Mac Catalyst)
- #81158 (Point to span of upvar making closure FnMut)
- #81176 (Improve safety of `LateContext::qpath_res`)
- #81287 (Split rustdoc JSON types into separately versioned crate)
- #81306 (Fuse inner iterator in FlattenCompat and improve related tests)
- #81333 (clean up some const error reporting around promoteds)
- #81459 (Fix rustdoc text selection for page titles)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Fix rustdoc text selection for page titles
Fixes text selection of page titles by placing the `h1.fqn span.in-band` element before `h1.fqn span.out-of-band`.
Before vs after:
https://user-images.githubusercontent.com/11315492/105768203-55708700-5f5c-11eb-924b-4e7527ffe147.mp4
Retry of PR #81397 due to merge conflicts confusing me. Recreated the same changes as in that PR, but now when I run `./x.py doc library/std`, no changes I make to `src/librustdoc/html/render/mod.rs` to the file are reflected in the built doc files, even if I delete the `build` folder. I'm guessing there's some cache I'm missing?
r? `@Nemo157`
clean up some const error reporting around promoteds
These are some error reporting simplifications enabled by https://github.com/rust-lang/rust/pull/80579.
Further simplifications are possible but could be blocked on making `const_err` a hard error.
r? ``````@oli-obk``````
Split rustdoc JSON types into separately versioned crate
For now just an in-tree change.
In the future, this may be exposed as a standalone crate with standard semver.
Improve safety of `LateContext::qpath_res`
This is my first rustc code change, inspired by hacking on clippy!
The first change is to clear cached `TypeckResults` from `LateContext` when visiting a nested item. I took a hint from [here](5e91c4ecc0/compiler/rustc_privacy/src/lib.rs (L1300)).
Clippy has a `qpath_res` util function to avoid a possible ICE in `LateContext::qpath_res`. But the docs of `LateContext::qpath_res` promise no ICE. So this updates the `LateContext` method to keep its promises, and removes the util function.
Related: rust-lang/rust-clippy#4545
CC ````````````@eddyb```````````` since you've done related work
CC ````````````@flip1995```````````` FYI
Improve safety of `LateContext::qpath_res`
This is my first rustc code change, inspired by hacking on clippy!
The first change is to clear cached `TypeckResults` from `LateContext` when visiting a nested item. I took a hint from [here](5e91c4ecc0/compiler/rustc_privacy/src/lib.rs (L1300)).
Clippy has a `qpath_res` util function to avoid a possible ICE in `LateContext::qpath_res`. But the docs of `LateContext::qpath_res` promise no ICE. So this updates the `LateContext` method to keep its promises, and removes the util function.
Related: rust-lang/rust-clippy#4545
CC ````````````@eddyb```````````` since you've done related work
CC ````````````@flip1995```````````` FYI
Use -target when linking binaries for Mac Catalyst
When running `rustc` with `-target x86_64-apple-ios-macabi`, the linker
eventually gets run with `-arch x86_64`, because the linker back end splits the
LLVM target triple and uses the first token as the target architecture. However,
this does not work for the Mac Catalyst ABI, which is a separate target from
Darwin.
Specifying the full target triple with `-target` allows Mac Catalyst binaries to
link and run.
closes#80202
rustdoc: Render HRTB correctly for bare functions
The angle brackets were not rendered, so code like this:
some_func: for<'a> fn(val: &'a i32) -> i32
would be rendered as:
some_func: fn'a(val: &'a i32) -> i32
However, rendering with angle brackets is still invalid syntax:
some_func: fn<'a>(val: &'a i32) -> i32
so now it renders correctly as:
some_func: for<'a> fn(val: &'a i32) -> i32
-----
However, note that this code:
some_trait: dyn for<'a> Trait<'a>
will still render as:
some_trait: dyn Trait<'a>
which is not invalid syntax, but is still unclear. Unfortunately I think
it's hard to fix that case because there isn't enough information in the
`rustdoc::clean::Type` that this code operates on. Perhaps that case can
be fixed in a later PR.
r? ``@jyn514``
Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` lint
cc #79813
This PR adds an allow-by-default future-compatibility lint
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS`. It fires when a trailing semicolon in a
macro body is ignored due to the macro being used in expression
position:
```rust
macro_rules! foo {
() => {
true; // WARN
}
}
fn main() {
let val = match true {
true => false,
_ => foo!()
};
}
```
The lint takes its level from the macro call site, and
can be allowed for a particular macro by adding
`#[allow(macro_trailing_semicolon)]`.
The lint is set to warn for all internal rustc crates (when being built
by a stage1 compiler). After the next beta bump, we can enable
the lint for the bootstrap compiler as well.
rustc: Stabilize `-Zrun-dsymutil` as `-Csplit-debuginfo`
This commit adds a new stable codegen option to rustc,
`-Csplit-debuginfo`. The old `-Zrun-dsymutil` flag is deleted and now
subsumed by this stable flag. Additionally `-Zsplit-dwarf` is also
subsumed by this flag but still requires `-Zunstable-options` to
actually activate. The `-Csplit-debuginfo` flag takes one of
three values:
* `off` - This indicates that split-debuginfo from the final artifact is
not desired. This is not supported on Windows and is the default on
Unix platforms except macOS. On macOS this means that `dsymutil` is
not executed.
* `packed` - This means that debuginfo is desired in one location
separate from the main executable. This is the default on Windows
(`*.pdb`) and macOS (`*.dSYM`). On other Unix platforms this subsumes
`-Zsplit-dwarf=single` and produces a `*.dwp` file.
* `unpacked` - This means that debuginfo will be roughly equivalent to
object files, meaning that it's throughout the build directory
rather than in one location (often the fastest for local development).
This is not the default on any platform and is not supported on Windows.
Each target can indicate its own default preference for how debuginfo is
handled. Almost all platforms default to `off` except for Windows and
macOS which default to `packed` for historical reasons.
Some equivalencies for previous unstable flags with the new flags are:
* `-Zrun-dsymutil=yes` -> `-Csplit-debuginfo=packed`
* `-Zrun-dsymutil=no` -> `-Csplit-debuginfo=unpacked`
* `-Zsplit-dwarf=single` -> `-Csplit-debuginfo=packed`
* `-Zsplit-dwarf=split` -> `-Csplit-debuginfo=unpacked`
Note that `-Csplit-debuginfo` still requires `-Zunstable-options` for
non-macOS platforms since split-dwarf support was *just* implemented in
rustc.
There's some more rationale listed on #79361, but the main gist of the
motivation for this commit is that `dsymutil` can take quite a long time
to execute in debug builds and provides little benefit. This means that
incremental compile times appear that much worse on macOS because the
compiler is constantly running `dsymutil` over every single binary it
produces during `cargo build` (even build scripts!). Ideally rustc would
switch to not running `dsymutil` by default, but that's a problem left
to get tackled another day.
Closes#79361
LLVM 12 no longer builds with Python 2, so install Python 3 in
preparatin.
However, Clang 10 does not build with Python 3, so we need update
to Clang 11 as well, which supports both.
Unfortunately, doing so results in errors while linking the
libLLVM.so into other binaries:
> __morestack: invalid needed version 2
This is fixed by using LLD instead. Possibly this is due to a binutils
linker bug, but updating to the latest binutils version does not fix
it.
Make hitting the recursion limit in projection non-fatal
This change was originally made in #80246 to avoid future (effectively) infinite loop bugs in projections,
but wundergraph relies on rustc recovering here.
cc #80953
r? `@nikomatsakis`
This commit adds a new stable codegen option to rustc,
`-Csplit-debuginfo`. The old `-Zrun-dsymutil` flag is deleted and now
subsumed by this stable flag. Additionally `-Zsplit-dwarf` is also
subsumed by this flag but still requires `-Zunstable-options` to
actually activate. The `-Csplit-debuginfo` flag takes one of
three values:
* `off` - This indicates that split-debuginfo from the final artifact is
not desired. This is not supported on Windows and is the default on
Unix platforms except macOS. On macOS this means that `dsymutil` is
not executed.
* `packed` - This means that debuginfo is desired in one location
separate from the main executable. This is the default on Windows
(`*.pdb`) and macOS (`*.dSYM`). On other Unix platforms this subsumes
`-Zsplit-dwarf=single` and produces a `*.dwp` file.
* `unpacked` - This means that debuginfo will be roughly equivalent to
object files, meaning that it's throughout the build directory
rather than in one location (often the fastest for local development).
This is not the default on any platform and is not supported on Windows.
Each target can indicate its own default preference for how debuginfo is
handled. Almost all platforms default to `off` except for Windows and
macOS which default to `packed` for historical reasons.
Some equivalencies for previous unstable flags with the new flags are:
* `-Zrun-dsymutil=yes` -> `-Csplit-debuginfo=packed`
* `-Zrun-dsymutil=no` -> `-Csplit-debuginfo=unpacked`
* `-Zsplit-dwarf=single` -> `-Csplit-debuginfo=packed`
* `-Zsplit-dwarf=split` -> `-Csplit-debuginfo=unpacked`
Note that `-Csplit-debuginfo` still requires `-Zunstable-options` for
non-macOS platforms since split-dwarf support was *just* implemented in
rustc.
There's some more rationale listed on #79361, but the main gist of the
motivation for this commit is that `dsymutil` can take quite a long time
to execute in debug builds and provides little benefit. This means that
incremental compile times appear that much worse on macOS because the
compiler is constantly running `dsymutil` over every single binary it
produces during `cargo build` (even build scripts!). Ideally rustc would
switch to not running `dsymutil` by default, but that's a problem left
to get tackled another day.
Closes#79361
