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 😅
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.
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.
Make backtraces work on Redox, copying Unix implementation
The `backtrace/` directory here is the same as the Unix one, except for adding an implementation of `get_executable_filename`.
Rewrite/reorganize docs for stack size/thread names for spawned threads.
* Moves docs about stack size and thread naming from `Builder` to the
`std::thread` module
* Adds more links to the new module-level documentation
* Mentions the 2 MiB stack size default, but indicate it's subject to
change
Fixes https://github.com/rust-lang/rust/issues/43805.
Instant is monotonically nondecreasing
We don't want to guarantee that `Instant::now() != Instant::now()` is
always true since that depends on the speed of the processor and the
resolution of the clock.
* Moves docs about stack size and thread naming from `Builder` to the
`std::thread` module
* Adds more links to the new module-level documentation
* Mentions the 2 MiB stack size default, but indicate it's subject to
change
Fixes https://github.com/rust-lang/rust/issues/43805.
Expose all OS-specific modules in libstd doc.
1. Uses the special `--cfg dox` configuration passed by rustbuild when running `rustdoc`. Changes the `#[cfg(platform)]` into `#[cfg(any(dox, platform))]` so that platform-specific API are visible to rustdoc.
2. Since platform-specific implementations often won't compile correctly on other platforms, `rustdoc` is changed to apply `everybody_loops` to the functions during documentation and doc-test harness.
3. Since platform-specific code are documented on all platforms now, it could confuse users who found a useful API but is non-portable. Also, their examples will be doc-tested, so must be excluded when not testing on the native platform. An undocumented attribute `#[doc(cfg(...))]` is introduced to serve the above purposed.
Fixes#24658 (Does _not_ fully implement #1998).
Check #[thread_local] statics correctly in the compiler.
Fixes#43733 by introducing `#[allow_internal_unsafe]` analogous to `#[allow_internal_unstable]`, for letting a macro expand to `unsafe` blocks and functions even in `#![forbid(unsafe_code)]` crates.
Fixes#17954 by not letting references to `#[thread_local]` statics escape the function they're taken in - we can't just use a magical lifetime because Rust has *lifetime parametrism*, so if we added the often-proposed `'thread` lifetime, we'd have no way to check it in generic code.
To avoid potential edge cases in the compiler, the lifetime is actually that of a temporary at the same position, i.e. `&TLS_STATIC` has the same lifetime `&non_const_fn()` would.
Referring to `#[thread_local]` `static`s at compile-time is banned now (as per PR discussion).
Additionally, to remove `unsafe impl Sync` from `std:🧵:local::fast::Key`, `#[thread_local]` statics are now not required to implement `Sync`, as they are not shared between threads.
Make a disable-jemalloc build work
Fixes#43510. I've tested this up to building a stage1 compiler.
r? @alexcrichton
cc @cuviper @vorner
@cuviper your fix was almost correct, you just had a stray `!` in there which caused the second error you saw.
Fixed mutable vars being marked used when they weren't
#### NB : bootstrapping is slow on my machine, even with `keep-stage` - fixes for occurances in the current codebase are <s>in the pipeline</s> done. This PR is being put up for review of the fix of the issue.
Fixes#43526, Fixes#30280, Fixes#25049
### Issue
Whenever the compiler detected a mutable deref being used mutably, it marked an associated value as being used mutably as well. In the case of derefencing local variables which were mutable references, this incorrectly marked the reference itself being used mutably, instead of its contents - with the consequence of making the following code emit no warnings
```
fn do_thing<T>(mut arg : &mut T) {
... // don't touch arg - just deref it to access the T
}
```
### Fix
Make dereferences not be counted as a mutable use, but only when they're on borrows on local variables.
#### Why not on things other than local variables?
* Whenever you capture a variable in a closure, it gets turned into a hidden reference - when you use it in the closure, it gets dereferenced. If the closure uses the variable mutably, that is actually a mutable use of the thing being dereffed to, so it has to be counted.
* If you deref a mutable `Box` to access the contents mutably, you are using the `Box` mutably - so it has to be counted.
Avoid calling the column!() macro in panic
Closes#43057
This "fix" adds a new macro called `__rust_unstable_column` and to use it instead of the `column` macro inside panic. The new macro can be shadowed as well as `column` can, but its very likely that there is no code that does this in practice.
There is no real way to make "unstable" macros that are usable by stable macros, so we do the next best thing and prefix the macro with `__rust_unstable` to make sure people recognize it is unstable.
r? @alexcrichton
