- fixes evaluation of array length for zero-sized type referenced by
rvalue operand.
- adds test to verify fix.
Cause of the issue.
Zero-sized aggregates are handled as operands, not lvalues. Therefore while
visiting Assign statement by LocalAnalyser, mark_as_lvalue() is not called for
related Local. This behaviour is controlled by rvalue_creates_operand() method.
As result it causes error later, when rvalue operand is evaluated in
trans_rvalue_operand() while handling Rvalue::Len case. Array length evaluation
invokes trans_lvalue() which expects referenced Local to be value, not operand.
How it is fixed.
In certain cases result of Rvalue::Len can be evaluated without calling
trans_lvalue(). Method evaluate_array_len() is introduced to handle length
evaluation for zero-sized types referenced by Locals.
Mention null_mut on the pointer primitive docs.
Also adds a few mentions that both `*const` and `*mut` support functions, when only `*const` was mentioned before.
libproc_macro docs: fix brace and bracket mixup
The documentation indicates that brace is `[`.
Brace is mapped token::Brace which (expectedly) is `{`.
So the documentation is simply confusing brace and bracket there.
Even though it's just a very small issue, it can lead to quite some confusion.
Redox: correct is_absolute() and has_root()
This is awkward, but representing schemes properly in `Components` is not easily possible without breaking backwards compatibility, as discussed earlier in https://github.com/rust-lang/rust/pull/37702.
But these methods can be corrected anyway.
Point "deref coercions" links to new book
Currently the link on doc.rust-lang.org is semi-broken; it links to a page that links to the exact page in the first edition in the book, or to the index of the second edition of the book. If the second editions
is the recommended one now, we should point the links at that one. (In the mean time, the links have been updated to point directly to the first edition of the book, but that hasn't made it onto
the stable channel yet.) By the time this commit makes it onto the stable channel, the second edition of the book should be complete enough. At least the part about deref coercions is.
r? @steveklabnik
Support dynamically-linked and/or native musl targets
These changes allow native compilation on musl-based distributions and the use of dynamic libraries on linux-musl targets. This is intended to remove limitations based on past assumptions about musl targets, while maintaining existing behavior by default.
A minor related bugfix is included.
Before `#[must_use]` for functions was implemented, a `#[must_use]` attribute
on a function was a no-op. To avoid a breaking change in this behavior, we add
an option for "this-and-such feature is experimental" feature-gate messages to
be a mere warning rather than a compilation-halting failure (so old code that
used to have a useless no-op `#[must_use]` attribute now warns rather than
breaking). When we're on stable, we add a help note to clarify that the feature
isn't "on."
This is in support of #43302.
std: Respect formatting flags for str-like OsStr
Historically many `Display` and `Debug` implementations for `OsStr`-like
abstractions have gone through `String::from_utf8_lossy`, but this was updated
in #42613 to use an internal `Utf8Lossy` abstraction instead. This had the
unfortunate side effect of causing a regression (#43765) in code which relied on
these `fmt` trait implementations respecting the various formatting flags
specified.
This commit opportunistically adds back interpretation of formatting trait flags
in the "common case" where where `OsStr`-like "thing" is all valid utf-8 and can
delegate to the formatting implementation for `str`. This doesn't entirely solve
the regression as non-utf8 paths will format differently than they did before
still (in that they will not respect formatting flags), but this should solve
the regression for all "real world" use cases of paths and such. The door's also
still open for handling these flags in the future!
Closes#43765
We'll actually want a new "soft" warning-only gate to maintain
backwards-compatibility, but it's cleaner to start out with the established,
well-understood gate before implementing the alternative warn-only behavior in
a later commit.
This is in the matter of #43302.
Fix logic error in test guarding prototype MIR borrowck code.
Fix logic error in test guarding prototype MIR borrowck code.
tl;dr: 🤦
(This crept in during the shift from a transform to a query (#44009); I didn't notice because my muscle memory was still always passing `-Z mir-borrowck`, while my test cases *also* had the `#[rustc_mir_borrowck]` attribute attached to them.)
Now that musl supports dynamic libraries (although not by default)
enable the tests that now pass. Additional currently-ignored tests
will pass if rustc is built with crt_static=false in config.toml.
Use libgcc_s when linking dynamically. Convert the static libunwind to
static-nobundle, as libunwind.a is copied from musl_root and available
in the library search path.
Static PIE support, while supported on musl, requires a patch to GCC.
Until/unless it is merged, adding '-pie' to the linker command line will
override '-static' and create a binary that requires a dynamic
interpreter (ld.so).
Most UNIX-like platforms do not allow shared libraries to statically
link their own libc, as libc expects to have consistent process-global
state. On those platforms, when we do not have a shared libc available,
we must not attempt to link dylibs or cdylibs. On Windows, however, it
is expected to statically link the CRT into dynamic libraries.
This feature is only relevant for targets that support both fully-static
and fully-dynamic linkage, such as musl on Linux.
This feature allows targets to opt in to full support of the crt-static
feature. Currently, crt-static is allowed on all targets, even those
that really can't or really shouldn't support it. This works because it
is very loose in the specification of its effects. Changing the behavior
of crt-static to be more strict in how it chooses libraries and links
executables would likely cause compilation to fail on these platforms.
To avoid breaking existing uses of crt-static, whitelist targets that
support the new, stricter behavior. For all other targets, this changes
crt-static from being "mostly a no-op" to "explicitly a no-op".
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.
They are required for linking it, even though it is a library, because
crtn.o in post_link_objects, as hardcoded in src/librustc_back/target/
linux_musl_base.rs, is added to the linker command line for both
executables and libraries.
Add the libraries and objects that have to be linked to a get working L4Re
Binary using pre- and post-link-args. Additionaly some ld commands had to
be passed.
* L4Re libraries and objects will be located by an environment variable.
* gcc libraries and objects will be located using a gcc call.
GCC is mandatory for this target, that might need documentation somewhere.
As soon as something mandatory cannot be found, the compiler will panic.
This is intended, because the functions involved don't allow the usage of
a Result type. libgcc_eh is now passed using `-l` and crtbeginT.o and
crtend.o are now located using `gcc -print-filename`.
Co-authored-by: TobiasSchaffner <tobiasschaffner@outlook.com>
Make sure crates not opting in to staged_api don't use staged_api
This also fixes the problem that with `-Zforce-unstable-if-unmarked` set, crates could not use `#[deprecated]`.
If you prefer, I can instead submit another version which just fixes this problem, but still allows the staged API attributes for all crates when `-Zforce-unstable-if-unmarked` is set. I have prepared that at <https://github.com/RalfJung/rust/tree/staged2>. As yet another alternative, @alexcrichton suggested to turn this error into a lint, but that seems to be much more work, so is it worth it?
Cc @alexcrichton #43975
(This crept in during the shift from a transform to a query; I didn't
notice because my muscle memory was still always passing `-Z
mir-borrowck`, while my test cases *also* had the
`#[rustc_mir_borrowck]` attribute attached to them.)
Add PartialEq/Eq impls to proc_macro::{Spacing, Delimiter}
I don't see a reason why those two types shouldn't be tested for equality. But I hardly know anything about proc macros, so I'm probably wrong :)
Point out missing if conditional
On a case where an else conditional is missing, point this out
instead of the token immediately after the (incorrect) else block:
```
error: missing condition for `if` statemementt push fork -f
--> $DIR/issue-13483.rs:16:5
|
13 | } else if {
| ^ expected if condition here
```
instead of
```
error: expected `{`, found `else`
--> ../../src/test/ui/issue-13483.rs:14:7
|
14 | } else {
| ^^^^
```
Fix#13483.
Generate builtin impls for `Clone`
This fixes a long-standing ICE and limitation where some builtin types implement `Copy` but not `Clone` (whereas `Clone` is a super trait of `Copy`).
However, this PR has a few side-effects:
* `Clone` is now marked as a lang item.
* `[T; N]` is now `Clone` if `T: Clone` (currently, only if `T: Copy` and for `N <= 32`).
* `fn foo<'a>() where &'a mut (): Clone { }` won't compile anymore because of how bounds for builtin traits are handled (e.g. same thing currently if you replace `Clone` by `Copy` in this example). Of course this function is unusable anyway, an error would pop as soon as it is called.
Hence, I'm wondering wether this PR would need an RFC...
Also, cc-ing @nikomatsakis, @arielb1.
Related issues: #28229, #24000.
syntax: Relax path grammar
TLDR: Accept the disambiguator `::` in "type" paths (`Type::<Args>`), accept the disambiguator `::` before parenthesized generic arguments (`Fn::(Args)`).
The "turbofish" disambiguator `::<>` in expression paths is a necessary evil required for path parsing to be both simple and to give reasonable results.
Since paths in expressions usually refer to values (but not necessarily, e.g. `Struct::<u8> { field: 0 }` is disambiguated, but refers to a type), people often consider `::<>` to be inherent to *values*, and not *expressions* and want to write disambiguated paths for values even in contexts where disambiguation is not strictly necessary, for example when a path is passed to a macro `m!(Vec::<i32>::new)`.
The problem is that currently, if the disambiguator is not *required*, then it's *prohibited*. This results in confusion - see https://github.com/rust-lang/rust/issues/41740, https://internals.rust-lang.org/t/macro-path-uses-novel-syntax/5561.
This PR makes the disambiguator *optional* instead of prohibited in contexts where it's not strictly required, so people can pass paths to macros in whatever form they consider natural (e.g. disambiguated form for value paths).
This PR also accepts the disambiguator in paths with parenthesized arguments (`Fn::(Args)`) for consistency and to simplify testing of stuff like https://github.com/rust-lang/rust/pull/41856#issuecomment-301219194.
Closes https://github.com/rust-lang/rust/issues/41740
cc @rust-lang/lang
r? @nikomatsakis
Mir borrowck as query
Turn the `mir-borrowck` pass (aka "transform") into a query.
(If I had realized how relatively easy this was going to be, I would have made it part of #43108. `let hindsight = 20/20;`)
rustc: Add `Local` to the HIR map of parents
When walking parents for lints we want to be sure to hit `let` statements which
can have attributes, so hook up these statements in the HIR map.
Closes#43910
Implements RFC 1845, adding implementations of:
* `From<&[T]>` for `Rc<[T]>`
* `From<&str>` for `Rc<str>`
* `From<String>` for `Rc<str>`
* `From<Box<T: ?Sized>>` for `Rc<T>`
* `From<Vec<T>>` for `Rc<[T]>`
* and likewise for `Arc<_>`
Also removes now-obsolete internal methods `Rc::__from_array` and
`Rc::__from_str`, replacing their use with `Rc::from`.
Minor rewrite of char primitive unicode intro.
Opened primarily to address #36998.
Despite my love for emoji, the heart example is a little confusing because both heart characters start with the same code point and there can be stark rendering differences across browsers. I also spelled out what each of the code points is in the code block, which (hopefully) sheds light why one character is one code point while the other is two.
Very much open to suggestion and improvements. I'm pretty tired when I wrote this so I might wake up and realize that this is making things more confusing 😅
Redox paths are problematic. It would make sense to add a `Scheme`
variant to the `std::path::Component` enum; but that would presumably be
a breaking change due to exhaustive matching. Alternately it could use
the existing `Prefix` variant, like Windows, but none of the existing
types of prefix make sense, Redox only has one kind, and adding a new
variant to that enum has the same issue as `Component`.
When walking parents for lints we want to be sure to hit `let` statements which
can have attributes, so hook up these statements in the HIR map.
Closes#43910
Eat open paren when parsing list in libsyntax/parse/attr.rs
This PR adds a small refactoring:
```diff
pub fn parse_meta_item_kind(&mut self) -> PResult<'a, ast::MetaItemKind> {
Ok(if self.eat(&token::Eq) {
ast::MetaItemKind::NameValue(self.parse_unsuffixed_lit()?)
- } else if self.token == token::OpenDelim(token::Paren) {
+ } else if self.eat(&token::OpenDelim(token::Paren)) {
ast::MetaItemKind::List(self.parse_meta_seq()?)
} else {
- self.eat(&token::OpenDelim(token::Paren));
ast::MetaItemKind::Word
})
}
```
in `parse_meta_item_kind()`, the parser calls `self.eat(&token::OpenDelim(token::Paren));` before returning `ast::MetaItemKind::Word` just to add `(` to expected token. It seems more natural to eat the paren when parsing `ast::MetaItemKind::List`.
Refactoring: move net specific file descriptor methods
Move the implementations of net specific file descriptor methods from
io to net. This makes it easier to exclude net at all if it is not needed
for a target.
Implement CompilerDesugaringKind enum
This is the first step outlined in #35946. I think that the variants of `CompilerDesugaringKind` should be changed, I didn't know what the official names for `...` and `<-` are.
I'm not to sure how tests for the compiler work, but I would imagine that tests should be added such that
`Symbol::intern(s) == CompilerDesugaringKind::from(s).as_symbol()` for valid `s`.
On a case where an else conditional is missing, point this out
instead of the token immediately after the (incorrect) else block:
```
error: missing condition for `if` statemementt push fork -f
--> $DIR/issue-13483.rs:16:5
|
13 | } else if {
| ^ expected if condition here
```
instead of
```
error: expected `{`, found `else`
--> ../../src/test/ui/issue-13483.rs:14:7
|
14 | } else {
| ^^^^
```
Fix ES5 regression with shorthand names.
Reverts 1b6c9605e4.
I appreciate new features and syntax in Rust, but seriously, don't rewrite anything. Especially if this **breaks** documentation of language itself and every crate hosted at docs.rs.
Implement a temp redirect for cargo docs
As discussed in
https://github.com/rust-lang/cargo/issues/4040#issuecomment-321639074
This is a redirect meant to be replaced once cargo docs have been
converted to mdbook. We just want *a* URL to ride the trains for now so
that we can print doc.rust-lang.org/cargo in the paper book and
guarantee that it will go *somewhere* useful by the time the book is
printed.
Implemented as a meta redirect in HTML because we don't currently have
any google juice at doc.rust-lang.org/cargo to lose.
When I run `./x.py doc`, this creates a `build/x86_64-apple-darwin/doc/cargo/index.html` file that contains a meta redirect to doc.crates.io. As I understand rust-central-station to work, this should be what we need to make `doc.rust-lang.org/cargo` to work.
r? @alexcrichton and/or @steveklabnik
Document that `std:#️⃣:Hasher::finish()` does not reset the hasher.
Clarifies the fact that `finish()` doesn’t in fact end or reset the hasher. This was surprising to me …
Follows up on and fixes#43763
Remove useless help part
Part of #32658.
I think this error should be splitted into two parts, each more specific (`anonymous function` vs `type method`).
As discussed in
https://github.com/rust-lang/cargo/issues/4040#issuecomment-321639074
This is a redirect meant to be replaced once cargo docs have been
converted to mdbook. We just want *a* URL to ride the trains for now so
that we can print doc.rust-lang.org/cargo in the paper book and
guarantee that it will go *somewhere* useful by the time the book is
printed.
Implemented as a meta redirect in HTML because we don't currently have
any google juice at doc.rust-lang.org/cargo to lose.
MIR borrow check (under debug flag)
Here is the current state of MIR borrow check.
It consists of (1.) some refactoring, (2.) a dataflow analysis to identify the borrows themselves, and (3.) a mir "transform" that does the borrow check itself based on the aforementioned dataflow results.
(There's also a drive-by fix to dataflow that I can factor into a separate PR if necessary. Interestingly I could not find a way to observe the bug outside of MIR borrowck.)
To be clear, this branch is not ready to be used as the default borrow check. Thus the code is guarded: To get mir-borrowck to run, you need to either supply an attribute `#[rustc_mir_borrowck]` or a debug flag `-Z borrowck-mir`.
Here are the main issues with the current MIR borrowck as it stands in this PR:
* No Notes emitted yet, just errors. (So the feedback is definitely inferior compared to AST borrowck today)
* Lvalue rendering differs between Ast and Mir. (Mostly minor, but replacement of field names with indices is very bad; big priority for me to fix ASAP.)
* Lots of ICEs (presumably because some MIR operations used here have well-formedness assumptions that are violated in borrowck-broken code)
* Conflates lots of cases that are distinguished by AST-borrowck
* Conflates "uninitialized" with "moved" (special case of previous bullet, one that I think should be fixed ASAP)
(I am hoping to fix as many of the above issues as I can in the near term, but I also would like to land this even if they are *not* all fixed, because the rebasing effort is getting to be a real drag.)
Added two fixmes: The `SimplifyBranches` pass cannot stay where it is,
and `BorrowckMir` should be a query, not a pass. But I am going to
leave those changes to a future PR.
One can either use `-Z borrowck-mir` or add the `#[rustc_mir_borrowck]` attribute
to opt into MIR based borrow checking.
Note that regardless of whether one opts in or not, AST-based borrow
check will still run as well. The errors emitted from AST-based
borrow check will include a "(Ast)" suffix in their error message,
while the errors emitted from MIR-based borrow check will include a
"(Mir)" suffix.
post-rebase: removed check for intra-statement mutual conflict;
replaced with assertion checking that at most one borrow is generated
per statement.
post-rebase: removed dead code: `IdxSet::pairs` and supporting stuff.
post-rebase: Do not put "(Ast)" suffix in error msg unless passed `-Z borrowck-mir`.
(But unconditionally include "(Mir)" suffix for mir-borrowck errors.)
Move the implementations of net specific file descriptior implementations
to net. This makes it easier to exclude net at all if not needed for a
target.
