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]
parameters.
This can break code that mistakenly used type parameters in place of
`Self`. For example, this will break:
trait Foo {
fn bar<X>(u: X) -> Self {
u
}
}
Change this code to not contain a type error. For example:
trait Foo {
fn bar<X>(_: X) -> Self {
self
}
}
Closes#15172.
[breaking-change]
r? @alexcrichton
This can break code that looked like:
struct S<T> {
val: T,
}
trait Gettable<T> {
...
}
impl<T: Copy> Gettable<T> for S<T> {
...
}
let t: Box<S<String>> = box S {
val: "one".to_string(),
};
let a = t as Box<Gettable<String>>;
// ^ note no `Copy` bound
Change this code to:
impl<T> Gettable<T> for S<T> {
// ^ remove `Copy` bound
...
}
Closes#14061.
[breaking-change]
with the corresponding trait parameter bounds.
This is a version of the patch in PR #12611 by Florian Hahn, modified to
address Niko's feedback.
It does not address the issue of duplicate type parameter bounds, nor
does it address the issue of implementation-defined methods that contain
*fewer* bounds than the trait, because Niko's review indicates that this
should not be necessary (and indeed I believe it is not). A test has
been added to ensure that this works.
This will break code like:
trait Foo {
fn bar<T:Baz>();
}
impl Foo for Boo {
fn bar<T:Baz + Quux>() { ... }
// ^~~~ ERROR
}
This will be rejected because the implementation requires *more* bounds
than the trait. It can be fixed by either adding the missing bound to
the trait:
trait Foo {
fn bar<T:Baz + Quux>();
// ^~~~
}
impl Foo for Boo {
fn bar<T:Baz + Quux>() { ... } // OK
}
Or by removing the bound from the impl:
trait Foo {
fn bar<T:Baz>();
}
impl Foo for Boo {
fn bar<T:Baz>() { ... } // OK
// ^ remove Quux
}
This patch imports the relevant tests from #2687, as well as the test
case in #5886, which is fixed as well by this patch.
Closes#2687.
Closes#5886.
[breaking-change]
r? @pnkfelix
parameters.
This can break code that mistakenly used type parameters in place of
`Self`. For example, this will break:
trait Foo {
fn bar<X>(u: X) -> Self {
u
}
}
Change this code to not contain a type error. For example:
trait Foo {
fn bar<X>(_: X) -> Self {
self
}
}
Closes#15172.
[breaking-change]
Slice patterns are different from the rest in that a single slice pattern
does not have a distinct constructor if it contains a variable-length subslice
pattern. For example, the pattern [a, b, ..tail] can match a slice of length 2, 3, 4
and so on.
As a result, the decision tree for exhaustiveness and redundancy analysis should
explore each of those constructors separately to determine if the pattern could be useful
when specialized for any of them.
with the corresponding trait parameter bounds.
This is a version of the patch in PR #12611 by Florian Hahn, modified to
address Niko's feedback.
It does not address the issue of duplicate type parameter bounds, nor
does it address the issue of implementation-defined methods that contain
*fewer* bounds than the trait, because Niko's review indicates that this
should not be necessary (and indeed I believe it is not). A test has
been added to ensure that this works.
This will break code like:
trait Foo {
fn bar<T:Baz>();
}
impl Foo for Boo {
fn bar<T:Baz + Quux>() { ... }
// ^~~~ ERROR
}
This will be rejected because the implementation requires *more* bounds
than the trait. It can be fixed by either adding the missing bound to
the trait:
trait Foo {
fn bar<T:Baz + Quux>();
// ^~~~
}
impl Foo for Boo {
fn bar<T:Baz + Quux>() { ... } // OK
}
Or by removing the bound from the impl:
trait Foo {
fn bar<T:Baz>();
}
impl Foo for Boo {
fn bar<T:Baz>() { ... } // OK
// ^ remove Quux
}
This patch imports the relevant tests from #2687, as well as the test
case in #5886, which is fixed as well by this patch.
Closes#2687.
Closes#5886.
[breaking-change]
Being able to index into the bytes of a string encourages
poor UTF-8 hygiene. To get a view of `&[u8]` from either
a `String` or `&str` slice, use the `as_bytes()` method.
Closes#12710.
[breaking-change]
I ended up altering the semantics of Json's PartialOrd implementation.
It used to be the case that Null < Null, but I can't think of any reason
for an ordering other than the default one so I just switched it over to
using the derived implementation.
This also fixes broken `PartialOrd` implementations for `Vec` and
`TreeMap`.
RFC: 0028-partial-cmp
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]
This change registers new snapshots, allowing `*T` to be removed from the language. This is a large breaking change, and it is recommended that if compiler errors are seen that any FFI calls are audited to determine whether they should be actually taking `*mut T`.
I believe that #5781 got fixed by the DST work. It duplicated the
variance inference work in #12828. Therefore, all that is left in #5781
is adding a test.
Closes#5781.
r? @huonw
This can break code that looked like:
impl Foo for Box<Any> {
fn f(&self) { ... }
}
let x: Box<Any + Send> = ...;
x.f();
Change such code to:
impl Foo for Box<Any> {
fn f(&self) { ... }
}
let x: Box<Any> = ...;
x.f();
That is, upcast before calling methods.
This is a conservative solution to #5781. A more proper treatment (see
the xfail'd `trait-contravariant-self.rs`) would take variance into
account. This change fixes the soundness hole.
Some library changes had to be made to make this work. In particular,
`Box<Any>` is no longer showable, and only `Box<Any+Send>` is showable.
Eventually, this restriction can be lifted; for now, it does not prove
too onerous, because `Any` is only used for propagating the result of
task failure.
This patch also adds a test for the variance inference work in #12828,
which accidentally landed as part of DST.
Closes#5781.
[breaking-change]
Since procs do not have lifetime bounds, we must do this to maintain
safety.
This can break code that incorrectly captured references in procedure
types. Change such code to not do this, perhaps with a trait object
instead.
A better solution would be to add higher-rank lifetime support to procs.
However, this would be a lot of work for a feature we want to remove in
favor of unboxed closures. The corresponding "real fix" is #15067.
Closes#14036.
[breaking-change]
It turns out that bindings introduced by 'for' loops were not treated hygienically. The fix for this is to make the 'for' expansion more like a macro; rather than expanding sub-pieces and then assembling them, we need to rewrite the for and then call expand again on the whole thing.
This PR includes a test and the fix.
It also contains a number of other things:
- unit tests for other forms of hygiene (currently ignored)
- a fix for the isaac.rs macro that (it turned out) was relying on capturing
- other miscellaneous cleanup and comments
This will break code like:
fn f(x: &mut int) {}
let mut a = box 1i;
f(a);
Change it to:
fn f(x: &mut int) {}
let mut a = box 1i;
f(&mut *a);
RFC 33; issue #10504.
[breaking-change]
r? @brson
vector-reference-to-unsafe-pointer-to-element cast if the type to be
casted to is not fully specified.
This is a conservative change to fix the user-visible symptoms of the
issue. A more flexible treatment would delay cast checks to after
function typechecking.
This can break code that did:
let x: *u8 = &([0, 0]) as *_;
Change this code to:
let x: *u8 = &([0, 0]) as *u8;
Closes#14893.
[breaking-change]
This will break code like:
fn f(x: &mut int) {}
let mut a = box 1i;
f(a);
Change it to:
fn f(x: &mut int) {}
let mut a = box 1i;
f(&mut *a);
RFC 33; issue #10504.
[breaking-change]
Closes#14482 (std: Bring back half of Add on String)
Closes#15026 (librustc: Remove the fallback to `int` from typechecking.)
Closes#15119 (Add more description to c_str::unwrap().)
Closes#15120 (Add tests for #12470 and #14285)
Closes#15122 (Remove the cheat sheet.)
Closes#15126 (rustc: Always include the morestack library)
Closes#15127 (Improve ambiguous pronoun.)
Closes#15130 (Fix#15129)
Closes#15131 (Add the Guide, add warning to tutorial.)
Closes#15134 (Xfailed tests for hygiene, etc.)
Closes#15135 (core: Add stability attributes to Clone)
Closes#15136 (Some minor improvements to core::bool)
Closes#15137 (std: Add stability attributes to primitive numeric modules)
Closes#15141 (Fix grammar in tutorial)
Closes#15143 (Remove few FIXMEs)
Closes#15145 (Avoid unnecessary temporary on assignments)
Closes#15147 (Small improvements for metaprogramming)
Closes#15153 (librustc: Check function argument patterns for legality of by-move)
Closes#15154 (test: Add a test for regions, traits, and variance.)
Closes#15159 (rustc: Don't register syntax crates twice)
Closes#13816 (Stabilize version output for rustc and rustdoc)
bindings.
This will break code that incorrectly did things like:
fn f(a @ box b: Box<String>) {}
Fix such code to not rely on undefined behavior.
Closes#12534.
[breaking-change]
The #14869 removed `TraitStore` from `ty_trait` and represented trait
reference as regular `ty_rptr`. An old bug of the missing constraint
upon lifetime parameter of trait reference then is fixed as a side
effect. Adds tests for affected bugs and closes them.
Closes#12470.
Closes#14285.
This breaks a fair amount of code. The typical patterns are:
* `for _ in range(0, 10)`: change to `for _ in range(0u, 10)`;
* `println!("{}", 3)`: change to `println!("{}", 3i)`;
* `[1, 2, 3].len()`: change to `[1i, 2, 3].len()`.
RFC #30. Closes#6023.
[breaking-change]
If you define lang items in your crate, add `#[feature(lang_items)]`.
If you define intrinsics (`extern "rust-intrinsic"`), add
`#[feature(intrinsics)]`.
Closes#12858.
[breaking-change]
Unit-like structs are written as `struct Foo;`, but we erroneously
accepted `struct Foo();` and took it to mean the same thing. Now we
don't, so use the `struct Foo;` form!
[breaking-change]
