It's not clear what this means, because a macro in item position can expand to zero or more items. For now we disallow it, which is technically a
[breaking-change]
but is landing without an RFC. The `pub` keyword previously had no effect, which seems quite unintended.
Fixes#18317.
Fixes#14660.
This PR replaces uses of `os::getenv` with newly introduced `env::var{,_os}`.
Mostly did this as a background activity to procrastinate from procrastinating.
Tests appear to build and run fine. This includes benchmarks from test/bench directory.
Some function signatures have changed, so this is a [breaking-change].
In particular, radixes and numerical values of digits are represented by `u32` now.
Part of #22240
It's not clear what this means, because a macro in item position can expand to
zero or more items. For now we disallow it, which is technically a
[breaking-change]
but is landing without an RFC. The `pub` keyword previously had no effect,
which seems quite unintended.
Fixes#18317.
Fixes#14660.
This commit tweaks the interface of the `std::env` module to make it more
ergonomic for common usage:
* `env::var` was renamed to `env::var_os`
* `env::var_string` was renamed to `env::var`
* `env::args` was renamed to `env::args_os`
* `env::args` was re-added as a panicking iterator over string values
* `env::vars` was renamed to `env::vars_os`
* `env::vars` was re-added as a panicking iterator over string values.
This should make common usage (e.g. unicode values everywhere) more ergonomic
as well as "the default". This is also a breaking change due to the differences
of what's yielded from each of these functions, but migration should be fairly
easy as the defaults operate over `String` which is a common type to use.
[breaking-change]
When projecting associate types for a trait's default methods, the
trait itself was added to the predicate candidate list twice: one from
parameter environment, the other from trait definition. Then the
duplicates were deemed as code ambiguity and the compiler rejected the
code. Simply checking and dropping the duplicates solves the issue.
Closes#22036
The live code analysis only visited the function's body when visiting a
method, and not the FnDecl and the generics, resulting in code to be
incorrectly marked as unused when it only appeared in the generics, the
arguments, or the return type, whereas the same code in non-method
functions was correctly detected as used. Fixes#20343.
Originally I just added a call to `walk_generics` and `walk_fndecl` alongside `walk_block` but then I noticed the `walk_method_helper` function did pretty much the same thing. The only difference is that it also calls `visit_mac`, but since this is not going to happen at this stage, I think it's ok. However let me know if this was not the right thing to do.
This commit tweaks the interface of the `std::env` module to make it more
ergonomic for common usage:
* `env::var` was renamed to `env::var_os`
* `env::var_string` was renamed to `env::var`
* `env::args` was renamed to `env::args_os`
* `env::args` was re-added as a panicking iterator over string values
* `env::vars` was renamed to `env::vars_os`
* `env::vars` was re-added as a panicking iterator over string values.
This should make common usage (e.g. unicode values everywhere) more ergonomic
as well as "the default". This is also a breaking change due to the differences
of what's yielded from each of these functions, but migration should be fairly
easy as the defaults operate over `String` which is a common type to use.
[breaking-change]
This is a resurrection and heavy revision/expansion of a PR that pcwalton did to resolve#8861.
The most relevant, user-visible semantic change is this: #[unsafe_destructor] is gone. Instead, if a type expression for some value has a destructor, then any lifetimes referenced within that type expression must strictly outlive the scope of the value.
See discussion on https://github.com/rust-lang/rfcs/pull/769
When projecting associate types for a trait's default methods, the
trait itself was added to the predicate candidate list twice: one from
parameter environment, the other from trait definition. Then the
duplicates were deemed as code ambiguity and the compiler rejected the
code. Simply checking and dropping the duplicates solves the issue.
Closes#22036
includes regression tests discovered during bootstrapping and tests of
cyclic structure that currently pass and are expected to continue
passing under the dropck rule.
(Note that all the uses of `unsafe_destructor` are just placating the
simple analysis used for that feature, which will eventually go away
once we have put the dropck through its paces.)
As the function comment already says, the types generated in the
foreign_signture function don't necessarily match the types used for a
corresponding rust function. Therefore we can't just use these types to
guide the translation of the wrapper function that bridges between the
external ABI and the rust ABI. Instead, we can query LLVM about the
types used in the rust function and use those to generate an appropriate
wrapper.
Fixes#21454
As the function comment already says, the types generated in the
foreign_signture function don't necessarily match the types used for a
corresponding rust function. Therefore we can't just use these types to
guide the translation of the wrapper function that bridges between the
external ABI and the rust ABI. Instead, we can query LLVM about the
types used in the rust function and use those to generate an appropriate
wrapper.
Fixes#21454
The live code analysis only visited the function's body when visiting a
method, and not the FnDecl and the generics, resulting in code to be
incorrectly marked as unused when it only appeared in the generics, the
arguments, or the return type, whereas the same code in non-method
functions was correctly detected as used. Fixes#20343.
Given `<expr> as Box<Trait>`, infer that `Box<_>` is expected type for `<expr>`.
This is useful for addressing fallout from newly proposed box protocol; see #22006 for examples of such fallout, much of which will be unnecessary with this fix.
Simplify cache selection by just using the local cache whenever there
are any where-clauses at all. This seems to be the simplest possible
rule and will (hopefully!) put an end to these annoying "cache leak"
bugs. Fixes#22019.
r? @aturon
Fixes#21833.
[breaking-change]
r? @alexcrichton
The tests in #21912 will also need `#[feature(no_std)]`. If you're okay with both PRs, I can merge and test them.
make `for PAT in ITER_EXPR { ... }` a terminating-scope for ITER_EXPR.
In effect, temporary anonymous values created during the evaluation of ITER_EXPR no longer not live for the entirety of the block surrounding the for-loop; instead they only live for the extent of the for-loop itself, and no longer.
----
There is one case I know of that this breaks, demonstrated to me by @nikomatsakis (but it is also a corner-case that is useless in practice). Here is that case:
```
fn main() {
let mut foo: Vec<&i8> = Vec::new();
for i in &[1, 2, 3] { foo.push(i) }
}
```
Note that if you add any code following the for-loop above, or even a semicolon to the end of it, then the code will stop compiling (i.e., it gathers a vector of references but the gathered vector cannot actually be used.)
(The above code, despite being useless, did occur in one run-pass test by accident; that test is updated here to accommodate the new striction.)
----
So, technically this is a:
[breaking-change]
closes#21630
Overloaded indexing (`&[mut] foo[bar]`) only works when `<Self as Index>::Output` is the same as `<Self as IndexMut>::Output` (see issue above). To restrict implementations of `IndexMut` that doesn't work, this PR makes `IndexMut` a supertrait over `Index`, i.e. `trait IndexMut<I>: Index<I>`, just like in the `trait DerefMut: Deref` case.
This breaks all downstream implementations of `IndexMut`, in most cases this simply means removing the `type Output = ..` bit, which is now redundant, from `IndexMut` implementations:
``` diff
impl Index<Foo> for Bar {
type Output = Baz;
..
}
impl IndexMut<Foo> for Bar {
- type Output = Baz;
..
}
```
[breaking-change]
---
r? @nikomatsakis