This allows code to access the fields of tuples and tuple structs:
let x = (1i, 2i);
assert_eq!(x.1, 2);
struct Point(int, int);
let origin = Point(0, 0);
assert_eq!(origin.0, 0);
assert_eq!(origin.1, 0);
- Ensures the propagated negation sign is properly utilized during type
checking.
- Removed redundant type checking, specifically regarding the out of bounds checking
on a bounded type.
- Closes#16684
This adds support for lint groups to the compiler. Lint groups are a way of
grouping a number of lints together under one name. For example, this also
defines a default lint for naming conventions, named `bad_style`. Writing
`#[allow(bad_style)]` is equivalent to writing
`#[allow(non_camel_case_types, non_snake_case, non_uppercase_statics)]`. These
lint groups can also be defined as a compiler plugin using the new
`Registry::register_lint_group` method.
This also adds two built-in lint groups, `bad_style` and `unused`. The contents
of these groups can be seen by running `rustc -W help`.
This unifies the `non_snake_case_functions` and `uppercase_variables` lints
into one lint, `non_snake_case`. It also now checks for non-snake-case modules.
This also extends the non-camel-case types lint to check type parameters, and
merges the `non_uppercase_pattern_statics` lint into the
`non_uppercase_statics` lint.
Because the `uppercase_variables` lint is now part of the `non_snake_case`
lint, all non-snake-case variables that start with lowercase characters (such
as `fooBar`) will now trigger the `non_snake_case` lint.
New code should be updated to use the new `non_snake_case` lint instead of the
previous `non_snake_case_functions` and `uppercase_variables` lints. All use of
the `non_uppercase_pattern_statics` should be replaced with the
`non_uppercase_statics` lint. Any code that previously contained non-snake-case
module or variable names should be updated to use snake case names or disable
the `non_snake_case` lint. Any code with non-camel-case type parameters should
be changed to use camel case or disable the `non_camel_case_types` lint.
[breaking-change]
[breaking-change]
1. The internal layout for traits has changed from (vtable, data) to (data, vtable). If you were relying on this in unsafe transmutes, you might get some very weird and apparently unrelated errors. You should not be doing this! Prefer not to do this at all, but if you must, you should use raw::TraitObject rather than hardcoding rustc's internal representation into your code.
2. The minimal type of reference-to-vec-literals (e.g., `&[1, 2, 3]`) is now a fixed size vec (e.g., `&[int, ..3]`) where it used to be an unsized vec (e.g., `&[int]`). If you want the unszied type, you must explicitly give the type (e.g., `let x: &[_] = &[1, 2, 3]`). Note in particular where multiple blocks must have the same type (e.g., if and else clauses, vec elements), the compiler will not coerce to the unsized type without a hint. E.g., `[&[1], &[1, 2]]` used to be a valid expression of type '[&[int]]'. It no longer type checks since the first element now has type `&[int, ..1]` and the second has type &[int, ..2]` which are incompatible.
3. The type of blocks (including functions) must be coercible to the expected type (used to be a subtype). Mostly this makes things more flexible and not less (in particular, in the case of coercing function bodies to the return type). However, in some rare cases, this is less flexible. TBH, I'm not exactly sure of the exact effects. I think the change causes us to resolve inferred type variables slightly earlier which might make us slightly more restrictive. Possibly it only affects blocks with unreachable code. E.g., `if ... { fail!(); "Hello" }` used to type check, it no longer does. The fix is to add a semicolon after the string.
int/uint aren't considered FFI safe, replace them with the actual type they
represent (i64/u64 or i32/u32). This is a breaking change, but at most a cast
to `uint` or `int` needs to be added.
[breaking-change]
As of RFC 18, struct layout is undefined. Opting into a C-compatible struct
layout is now down with #[repr(C)]. For consistency, specifying a packed
layout is now also down with #[repr(packed)]. Both can be specified.
To fix errors caused by this, just add #[repr(C)] to the structs, and change
#[packed] to #[repr(packed)]
Closes#14309
[breaking-change]
declared with the same name in the same scope.
This breaks several common patterns. First are unused imports:
use foo::bar;
use baz::bar;
Change this code to the following:
use baz::bar;
Second, this patch breaks globs that import names that are shadowed by
subsequent imports. For example:
use foo::*; // including `bar`
use baz::bar;
Change this code to remove the glob:
use foo::{boo, quux};
use baz::bar;
Or qualify all uses of `bar`:
use foo::{boo, quux};
use baz;
... baz::bar ...
Finally, this patch breaks code that, at top level, explicitly imports
`std` and doesn't disable the prelude.
extern crate std;
Because the prelude imports `std` implicitly, there is no need to
explicitly import it; just remove such directives.
The old behavior can be opted into via the `import_shadowing` feature
gate. Use of this feature gate is discouraged.
This implements RFC #116.
Closes#16464.
[breaking-change]
methods.
This paves the way to associated items by introducing an extra level of
abstraction ("impl-or-trait item") between traits/implementations and
methods. This new abstraction is encoded in the metadata and used
throughout the compiler where appropriate.
There are no functional changes; this is purely a refactoring.
Previously the lint considered cross-crate items only. That's
appropriate for unstable and experimental levels, but not for
deprecation.
Closes#16409
Due to deny(deprecation), this is a:
[breaking-change]
The `type_overflow` lint, doesn't catch the overflow for `i64` because
the overflow happens earlier in the parse phase when the `u64` as biggest
possible int gets casted to `i64` , without checking the for overflows.
We can't lint in the parse phase, so a refactoring of the `LitInt` type
was necessary.
The types `LitInt`, `LitUint` and `LitIntUnsuffixed` where merged to one
type `LitInt` which stores it's value as `u64`. An additional parameter was
added which indicate the signedness of the type and the sign of the value.
I think this is an improvement of the previous warning message, which
- like the comment that I removed implies - is in need of some
improvement.
I've opted to point the user in the right direction w.r.t how to fix the
problem, which I think is good form.
Not being familiar with the repr(...) attribute, I personally had to
check the lint rules myself to figure out what was wrong. Hopefully,
this will save he next person some time and headache.
Signed-off-by: Anton Lofgren <alofgren@op5.com>
This small patch causes the stability lint to bail out when traversing
any AST produced via a macro expansion. Ultimately, we would like to
lint the contents of the macro at the place where the macro is defined,
but regardless we should not be linting it at the use site.
Closes#15703
* Don't warn about `#[crate_name]` if `--crate-name` is specified
* Don't warn about non camel case identifiers on `#[repr(C)]` structs
* Switch `mode` to `mode_t` in libc.
C structs predominately do not use camel case identifiers, and we have a clear
indicator for what's a C struct now, so excuse all of them from this stylistic
lint.
Similar to the stability attributes, a type annotated with `#[must_use =
"informative snippet"]` will print the normal warning message along with
"informative snippet". This allows the type author to provide some
guidance about why the type should be used.
This was parsed by the parser but completely ignored; not even stored in
the AST!
This breaks code that looks like:
static X: &'static [u8] = &'static [1, 2, 3];
Change this code to the shorter:
static X: &'static [u8] = &[1, 2, 3];
Closes#15312.
[breaking-change]
Rationale: for what appear to be historical reasons only, the PatIdent contains
a Path rather than an Ident. This means that there are many places in the code
where an ident is artificially promoted to a path, and---much more problematically---
a bunch of elements from a path are simply thrown away, which seems like an invitation
to some really nasty bugs.
This commit replaces the Path in a PatIdent with a SpannedIdent, which just contains an ident
and a span.
This commit hooks rustdoc into the stability index infrastructure in two
ways:
1. It looks up stability levels via the index, rather than by manual
attributes.
2. It adds stability level information throughout rustdoc output, rather
than just at the top header. In particular, a stability color (with
mouseover text) appears next to essentially every item that appears
in rustdoc's HTML output.
Along the way, the stability index code has been lightly refactored.
floating point numbers for real.
This will break code that looks like:
let mut x = 0;
while ... {
x += 1;
}
println!("{}", x);
Change that code to:
let mut x = 0i;
while ... {
x += 1;
}
println!("{}", x);
Closes#15201.
[breaking-change]
Also change some code formatting.
lint::builtin becomes a sibling of lint::context in order to ensure that lints
implemented there use the same public API as lint plugins.
