Handle them in `middle::reachable` instead (no optimizations so far, just drop all trait impl items into the reachable set, as before). Addresses the concerns from https://github.com/rust-lang/rust/pull/29291#discussion_r43672413
\+ In `middle::reachable` don't treat impls of `Drop` specially, they are subsumed by the general impl treatment.
\+ Add some tests checking reachability of trait methods written in UFCS form
\+ Minor refactoring in the second commit
r? @alexcrichton
Old doctest names
```bash
test sync::atomic::load_0 ... ok
test sync::atomic::load_0 ... ok
test sync::atomic::load_0 ... ok
test sync::atomic::load_0 ... ok
```
New doctest names
```bash
test sync::atomic::AtomicBool::load_0 ... ok
test sync::atomic::AtomicIsize::load_0 ... ok
test sync::atomic::AtomicPtr<T>::load_0 ... ok
test sync::atomic::AtomicUsize::load_0 ... ok
```
Introduce a `SwitchInt` and restructure pattern matching to collect integers and characters into one master switch. This is aimed at #29227, but is not a complete fix. Whereas before we generated an if-else-if chain and, at least on my machine, just failed to compile, we now spend ~9sec compiling `rustc_abuse`. AFAICT this is basically just due to a need for more micro-optimization of the matching process: perf shows a fair amount of time just spent iterating over the candidate list. Still, it seemed worth opening a PR with this step alone, since it's a big step forward.
Currently if a print happens while a thread is being torn down it may cause a
panic if the LOCAL_STDOUT TLS slot has been destroyed by that point. This adds a
guard to check and prints to the process stdout if that's the case (as we do for
if the slot is already borrowed).
Closes#29488
As discovered in #29298, `env::set_var("", "")` will panic, but it turns out
that it *also* deadlocks on Unix systems. This happens because if a panic
happens while holding the environment lock, we then go try to read
RUST_BACKTRACE, grabbing the environment lock, causing a deadlock.
Specifically, the changes made here are:
* The environment lock is pushed into `std::sys` instead of `std::env`. This
also only puts it in the Unix implementation, not Windows where the functions
are already threadsafe.
* The `std::sys` implementation now returns `io::Result` so panics are
explicitly at the `std::env` level.
vec: Remove old comment in Vec::drop
This comment was leftover from an earlier revision of a PR, something
that never was merged. There is no ZST special casing in Vec::drop.
Originally, this was my 30 minute introduction, and we eventually made
it the opener to the book. But as #25918 has shown, the example I use
here has some issues. The good news is that Rust makes heap allocation
syntatically expensive, but the bad news is that that means showing
equivalent programs from Rust and other languages is difficult. After
thinking about it, I'm not sure this section is pulling its weight, and
since it has problems, I'd rather just pull it than try to re-write it
right now. I think the book is fine without it.
FIxes#25918
Rustdoc pages with a search box inadvertently override `ctrl-s` in addition to the intended `s` and `S` keys. You can test this in at least Firefox and Chrome (tested: Windows): press `ctrl-s` on http://doc.rust-lang.org/std/. The search box is focused when instead the browser's save feature should be activated. This PR fixes `ctrl-s` and possibly other browser shortcuts.
Rustdoc takes the first paragraph as a summary, so having a huge
paragraph that ends with introducing an example looked somewhat wrong on
the module page.
Originally, this was my 30 minute introduction, and we eventually made
it the opener to the book. But as #25918 has shown, the example I use
here has some issues. The good news is that Rust makes heap allocation
syntatically expensive, but the bad news is that that means showing
equivalent programs from Rust and other languages is difficult. After
thinking about it, I'm not sure this section is pulling its weight, and
since it has problems, I'd rather just pull it than try to re-write it
right now. I think the book is fine without it.
FIxes#25918
Rustdoc takes the first paragraph as a summary, so having a huge
paragraph that ends with introducing an example looked somewhat wrong on
the module page.
Reword "Writing the logic" paragraph to prevent `unwrap` being confused for a macro (and other small changes to improve the flow of the paragraph).
cc @steveklabnik
I did some preliminary editing work with No Starch on the first chapter of the book, and here's some of the results. We're going to want to return to this later when @brson etc's new rustup work is done, so this is mostly just a first pass.
But, we agreed that having separate chapters for each of this bit of intro is a bit excessive. So let's move all of this intro stuff into one chapter.
I'd appreciate a careful review of this, as there was also some confusion about some things, which resulted in me taking one huge markdown file apart and splitting it back up, as well as some editor issues, so I _think_ this looks good, but double checking things matters!
/cc @aturon
If you try to put something that's bigger than a char into a char
literal, you get an error:
fn main() {
let c = 'ஶ்ரீ';
}
error: unterminated character constant:
This is a very compiler-centric message. Yes, it's technically
'unterminated', but that's not what you, the user did wrong.
Instead, this commit changes it to
error: character literal that's larger than a char:
As this actually tells you what went wrong.
Fixes#28851
If you try to put something that's bigger than a char into a char
literal, you get an error:
fn main() {
let c = 'ஶ்ரீ';
}
error: unterminated character constant:
This is a very compiler-centric message. Yes, it's technically
'unterminated', but that's not what you, the user did wrong.
Instead, this commit changes it to
error: character literal may only contain one codepoint
As this actually tells you what went wrong.
Fixes#28851
