Increases heap size available during testing for SGX
PR [61540](https://github.com/rust-lang/rust/pull/61540) causes at least one test to fail when run for the SGX platform due to lack of memory. This PR increases the heapsize available during tests, which is a good thing regardless of the status of that PR.
Implementation of RFC 2289 (associated_type_bounds)
This PR implements the [`asociated_type_bounds` feature](https://github.com/rust-lang/rfcs/blob/master/text/2289-associated-type-bounds.md).
Associated type bounds are implemented in:
- function/method arguments and return types
- structs, enums, unions
- associated items in traits
- type aliases
- type parameter defaults
- trait objects
- let bindings
CC @nikomatsakis @centril
std: Update dependency on `backtrace`
Discovered in #61416 an accidental regression in libstd's backtrace
behavior is that it previously attempted to consult libbacktrace and
would then fall back to `dladdr` if libbacktrace didn't report anything.
The `backtrace` crate, however, did not do this, so that's now been
fixed!
Changes: https://github.com/rust-lang/backtrace-rs/compare/0.3.25...0.3.29Closes#61416
Discovered in #61416 an accidental regression in libstd's backtrace
behavior is that it previously attempted to consult libbacktrace and
would then fall back to `dladdr` if libbacktrace didn't report anything.
The `backtrace` crate, however, did not do this, so that's now been
fixed!
Changes: https://github.com/rust-lang/backtrace-rs/compare/0.3.25...0.3.27Closes#61416
std::net: Ipv4Addr and Ipv6Addr improvements
Picking this up again from my previous PR: https://github.com/rust-lang/rust/pull/56050
Related to: https://github.com/rust-lang/rust/issues/27709
Fixes: https://github.com/rust-lang/rust/issues/57558
- add `add Ipv4Addr::is_reserved()`
- [X] implementation
- [X] tests
- add `Ipv6Addr::is_unicast_link_local_strict()` and update `Ipv6Addr::is_unicast_link_local()` documentation
- [X] implementation
- [X] test
- add `Ipv4Addr::is_benchmarking()`
- [X] implementation
- [X] test
- add `Ipv4Addr::is_ietf_protocol_assignment()`
- [X] implementation
- [X] test
- add `Ipv4Addr::is_shared()`
- [X] implementation
- [x] test
- fix `Ipv4Addr:is_global()`
- [X] implementation
- [x] test
- [X] refactor the tests for IP properties. This makes the tests more verbose, but using macros have two advantages:
- it will now be easier to add tests for all the new methods
- we get clear error messages when a test is failing. For instance:
```
---- net::ip::tests::ip_properties stdout ----
thread '<unnamed>' panicked at 'assertion failed: !ip!("fec0::").is_global()', src/libstd/net/ip.rs:2036:9
```
Whereas previously it was something like
```
thread '<unnamed>' panicked at 'assertion failed: `(left == right)`
left: `true`,
right: `false`', libstd/net/ip.rs:1948:13
```
-----------------------
# Ongoing discussions:
## Should `Ipv4Addr::is_global()` return `true` or `false` for reserved addresses?
Reserved addresses are addresses that are matched by `Ipv4Addr::is_reserved()`.
@the8472 [pointed out](https://github.com/rust-lang/rust/pull/60145#issuecomment-485458319) that [RFC 4291](https://tools.ietf.org/html/rfc4291#section-2.4) says IPv6 reserved addresses should be considered global:
```
Future specifications may redefine one or more sub-ranges of the
Global Unicast space for other purposes, but unless and until that
happens, implementations must treat all addresses that do not start
with any of the above-listed prefixes as Global Unicast addresses.
```
We could extrapolate that this should also be the case for IPv4. However, it seems that [IANA considers them non global](https://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml) (see [my comment](https://github.com/rust-lang/rust/pull/60145#issuecomment-485713270))
### Final decision
There seems to be a consensus that reserved addresses have a different meaning for IPv4 and IPv6 ([comment1](https://github.com/rust-lang/rust/pull/60145#issuecomment-485963789) [comment2](https://github.com/rust-lang/rust/pull/60145#issuecomment-485944582), so we can consider that RFC4291 does not apply to IPv4, and that reserved IPv4 addresses are _not_ global.
## Should `Ipv6Addr::is_unicast_site_local()` exist?
@pusateri [noted](https://github.com/rust-lang/rust/pull/60145#issuecomment-485507515) that site-local addresses have been deprecated for a while by [RFC 3879](https://tools.ietf.org/html/rfc3879) and new implementations _must not_ support them. However, since this method is stable, removing does not seem possible. This kind of situation is covered by the RFC which stated that existing implementation _may_ continue supporting site-local addresses.
### Final decision
Let's keep this method. It is stable already, and the RFC explicitly states that existing implementation may remain.
---------
Note: I'll be AFK from April 27th to May 11th. Anyone should feel free to pick this up if the PR hasn't been merged by then. Sorry for dragging that for so long already.
error: remove StringError from Debug output
Seeing `StringError("something something")` in debug output can cause
someone to think there was an error dealing with `String`s, not that the
error type is just a string. So, remove that noise.
For example:
```
io error: Custom { kind: InvalidData, error: StringError("corrupt data") }
```
With this change:
```
io error: Custom { kind: InvalidData, error: "corrupt data" }
```
Warn on bare_trait_objects by default
The `bare_trait_objects` lint is set to `warn` by default.
Most ui tests have been updated to use `dyn` to avoid creating noise in stderr files.
r? @Centril
cc #54910
Print PermissionExt::mode() in octal in Documentation Examples
Printing the file permission mode on unix systems in decimal feels unintuitive. Printing it in octal gives the expected form of e.g. `664`.
This commit removes all in-tree support for generating backtraces in
favor of depending on the `backtrace` crate on crates.io. This resolves
a very longstanding piece of duplication where the standard library has
long contained the ability to generate a backtrace on panics, but the
code was later extracted and duplicated on crates.io with the
`backtrace` crate. Since that fork each implementation has seen various
improvements one way or another, but typically `backtrace`-the-crate has
lagged behind libstd in one way or another.
The goal here is to remove this duplication of a fairly critical piece
of code and ensure that there's only one source of truth for generating
backtraces between the standard library and the crate on crates.io.
Recently I've been working to bring the `backtrace` crate on crates.io
up to speed with the support in the standard library which includes:
* Support for `StackWalkEx` on MSVC to recover inline frames with
debuginfo.
* Using `libbacktrace` by default on MinGW targets.
* Supporting `libbacktrace` on OSX as an option.
* Ensuring all the requisite support in `backtrace`-the-crate compiles
with `#![no_std]`.
* Updating the `libbacktrace` implementation in `backtrace`-the-crate to
initialize the global state with the correct filename where necessary.
After reviewing the code in libstd the `backtrace` crate should be at
exact feature parity with libstd today. The backtraces generated should
have the same symbols and same number of frames in general, and there's
not known divergence from libstd currently.
Note that one major difference between libstd's backtrace support and
the `backtrace` crate is that on OSX the crates.io crate enables the
`coresymbolication` feature by default. This feature, however, uses
private internal APIs that aren't published for OSX. While they provide
more accurate backtraces this isn't appropriate for libstd distributed
as a binary, so libstd's dependency on the `backtrace` crate explicitly
disables this feature and forces OSX to use `libbacktrace` as a
symbolication strategy.
The long-term goal of this refactoring is to eventually move us towards
a world where we can drop `libbacktrace` entirely and simply use Gimli
and the surrounding crates for backtrace support. That's still aways off
but hopefully will much more easily enabled by having the source of
truth for backtraces live in crates.io!
Procedurally if we go forward with this I'd like to transfer the
`backtrace-rs` crate to the rust-lang GitHub organization as well, but I
figured I'd hold off on that until we get closer to merging.
Revert "Add implementations of last in terms of next_back on a bunch of DoubleEndedIterators."
This changed observable behavior for several iterator types.
r? @alexcrichton
This commit bumps the `compiler-builtins` dependency to 0.1.15 which
expects to have the source for `compiler-rt` provided externally if the
`c` feature is enabled. This then plumbs through the necessary support
in the build system to ensure that if the `llvm-project` directory is
checked out and present that we enable the `c` feature of
`compiler-builtins` and compile in all the C intrinsics.
Fix intra-doc link resolution failure on re-exporting libstd
Currently, re-exporting libstd items as below will [occur a lot of failures](https://gist.github.com/taiki-e/e33e0e8631ef47f65a74a3b69f456366).
```rust
pub use std::*;
```
Until the underlying issue (#56922) fixed, we can fix that so they don't propagate to downstream crates.
Related: https://github.com/rust-lang/rust/pull/56941 (That PR fixed failures that occur when re-exporting from libcore to libstd.)
r? @QuietMisdreavus
stabilize core parts of MaybeUninit
and deprecate mem::uninitialized in the future (1.40.0). This is part of implementing https://github.com/rust-lang/rfcs/pull/1892.
Also expand the documentation a bit.
This type is currently primarily useful when dealing with partially initialized arrays. In libstd, it is used e.g. in `BTreeMap` (with some unstable APIs that however can all be replaced, less ergonomically, by stable ones). What we stabilize should also be enough for `SmallVec` (Cc @bluss).
Making this useful for structs requires https://github.com/rust-lang/rfcs/pull/2582 or a commitment that references to uninitialized data are not insta-UB.
Remove the unstable and deprecated mpsc_select
This removes macro `select!` and `std::sync::mpsc::{Handle, Select}`,
which were all unstable and have been deprecated since 1.32.
Closes#27800
r? @SimonSapin
Prevent Error::type_id overrides
type_id now takes an argument that can't be named outside of the
std::error module, which prevents any implementations from overriding
it. It's a pretty grody solution, and there's no way we can stabilize
the method with this API, but it avoids the soudness issue!
Closes#60784
r? @alexcrichton
This updates to 0.1.13 for `compiler_builtins`, published to fix a few
issues. The feature changes here are updated because `compiler_builtins`
no longer enables the `c` feature by default but we want to do so
through our build still.
Closes#60747Closes#60782
Add stubs to keyword docs
Resolves#60779.
This commit gives each stable keyword a short entry in the "Keywords" section in the docs for `std`. The newly added entries are only a single line each and contain the main purpose of the keyword. I changed some of the existing summary lines for consistency's sake. Each line is either an imperative ("name the type of a trait object" for `dyn`), or an object ("An abstract data type" for `enum`). I tried to avoid using the keyword itself or the word "keyword" in the summary.
Later commits can flesh out each keyword with an example for each context in which it can appear as well as a link to the appropriate part of the rust book.
**edit:**
Here's the list of keywords and summaries (sans formatting) to ease reviewing. I'll try to keep this up to date as I make changes:
keyword | summary
-- | --
Self | The implementing type within a `trait` or `impl` block, or the current type within a type definition.
as | Cast between types, or rename an import.
async | ExperimentalReturn a Future instead of blocking the current thread.
await | ExperimentalSuspend execution until the result of a Future is ready.
break | Exit early from a loop.
const | Compile-time constants and deterministic functions.
continue | Skip to the next iteration of a loop.
crate | A Rust binary or library.
dyn | Name the type of a trait object.
else | What to do when an if condition does not hold.
enum | A type that can be any one of several variants.
extern | Link to or import external code.
false | A value of type bool representing logical false.
fn | A function or function pointer.
for | Iteration with in, trait implementation with impl, or higher-ranked trait bounds (for<'a>).
if | Evaluate a block if a condition holds.
impl | Implement some functionality for a type.
in | Iterate over a series of values with for.
let | Bind a value to a variable.
loop | Loop indefinitely.
match | Control flow based on pattern matching.
mod | Organize code into modules.
move | Capture a closure's environment by value.
mut | A mutable binding, reference, or pointer.
pub | Make an item visible to others.
ref | Bind by reference during pattern matching.
return | Return a value from a function.
self | The receiver of a method, or the current module.
static | A place that is valid for the duration of a program.
struct | A type that is composed of other types.
super | The parent of the current module.
trait | A common interface for a class of types.
true | A value of type bool representing logical true.
type | Define an alias for an existing type.
union | The Rust equivalent of a C-style union.
unsafe | Code or interfaces whose memory safety cannot be verified by the type system.
use | Import or rename items from other crates or modules.
where | Add constraints that must be upheld to use an item.
while | Loop while a condition is upheld.
