Improve backtrace formating while panicking.
Fixes#37783.
Done:
- Fix alignment of file paths for better readability
- `RUST_BACKTRACE=full` prints all the informations (current behaviour)
- `RUST_BACKTRACE=(short|yes)` is the default and does:
- Skip irrelevant frames at the beginning and the end
- Remove function address
- Remove the current directory from the absolute paths
- Remove `::hfabe6541873` at the end of the symbols
- `RUST_BACKTRACE=(0|no)` disables the backtrace.
- `RUST_BACKTRACE=<everything else>` is equivalent to `short` for
backward compatibility.
- doc
- More uniform printing across platforms.
Removed, TODO in a new PR:
- Remove path prefix for libraries and libstd
Example of short backtrace:
```rust
fn fail() {
panic!();
}
fn main() {
let closure = || fail();
closure();
}
```
Short:
```
thread 'main' panicked at 'explicit panic', t.rs:2
Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
0: t::fail
at ./t.rs:2
1: t::main::{{closure}}
at ./t.rs:6
2: t::main
at ./t.rs:7
```
Full:
```
thread 'main' panicked at 'This function never returns!', t.rs:2
stack backtrace:
0: 0x558ddf666478 - std::sys:👿:backtrace::tracing:👿:unwind_backtrace::hec84c9dd8389cc5d
at /home/yamakaky/dev/rust/rust/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
1: 0x558ddf65d90e - std::sys_common::backtrace::_print::hfa25f8b31f4b4353
at /home/yamakaky/dev/rust/rust/src/libstd/sys_common/backtrace.rs:71
2: 0x558ddf65cb5e - std::sys_common::backtrace::print::h9b711e11ac3ba805
at /home/yamakaky/dev/rust/rust/src/libstd/sys_common/backtrace.rs:60
3: 0x558ddf66796e - std::panicking::default_hook::{{closure}}::h736d216e74748044
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:355
4: 0x558ddf66743c - std::panicking::default_hook::h16baff397e46ea10
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:371
5: 0x558ddf6682bc - std::panicking::rust_panic_with_hook::h6d5a9bb4eca42c80
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:559
6: 0x558ddf64ea93 - std::panicking::begin_panic::h17dc549df2f10b99
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:521
7: 0x558ddf64ec42 - t::diverges::he6bc43fc925905f5
at /tmp/p/t.rs:2
8: 0x558ddf64ec5a - t::main::h0ffc20356b8a69c0
at /tmp/p/t.rs:6
9: 0x558ddf6687f5 - core::ops::FnOnce::call_once::hce41f19c0db56f93
10: 0x558ddf667cde - std::panicking::try::do_call::hd4c8c97efb4291df
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:464
11: 0x558ddf698d77 - __rust_try
12: 0x558ddf698c57 - __rust_maybe_catch_panic
at /home/yamakaky/dev/rust/rust/src/libpanic_unwind/lib.rs:98
13: 0x558ddf667adb - std::panicking::try::h2c56ed2a59ec1d12
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:440
14: 0x558ddf66cc9a - std::panic::catch_unwind::h390834e0251cc9af
at /home/yamakaky/dev/rust/rust/src/libstd/panic.rs:361
15: 0x558ddf6809ee - std::rt::lang_start::hb73087428e233982
at /home/yamakaky/dev/rust/rust/src/libstd/rt.rs:57
16: 0x558ddf64ec92 - main
17: 0x7fecb869e290 - __libc_start_main
18: 0x558ddf64e8b9 - _start
19: 0x0 - <unknown>
```
Loop docs: Present perfect instead of simple past
Sounds better with present perfect because there's a link to the present.
I'm not a native speaker, though. So, plz check whether it really is better ;)
r? @steveklabnik
doc: Use "macOS" terminology consistently
One line in the documentation used the term macOS while the other six used OSX. Be consistent and use the current product brand of macOS.
Add Gankro's table to nomicon/src/phantom-data.md
Original: https://github.com/rust-lang/rust/issues/30069#issuecomment-159928136
Testing confirms that:
- `PhantomData<fn() -> T>` does not actually enable drop checking.
- `PhantomData<fn(T) -> T>` is neither variant nor contravariant.
Correct another typo in procedural macros chapter of the Book.
Another (and the only remaining) instance of the lets/let's mistake fixed in c8292fc / 36b00cf.
r? @steveklabnik
Add Documentation for Custom Attributes and Error Reporting in Procedural Macros
This fixes#39821 .
I'm not sure if the process of how to access custom attributes should be documented as well.
But I feel, that this should rather be documented in `syn`
book: binary prefixed are defined by IEC and not in SI
Binary prefixes (such as Gi for ‘gibi-’ in GiB) are defined by
International Electrotechnical Commission (IEC) and not in the
International System of Units (SI).
Though to be honest I’d just reword the previous paragraph to use ‘1 GiB’.
Reenable linkchecker for books
In some senses, this is a revert of https://github.com/rust-lang/rust/pull/39633/commits/cacb3bc9c741a7d41a1085af850cd3ff852307f5#diff-b64563d143f859565c8357a28ef81101R212; we disabled linkchecker for the book because the links were added by JavaScript. Now, that's fixed upstream, and so we can re-enable the checker.
This also involves two other fixes: we have to check for `name`s as well as `id`s for links, and the linking algorithm of mdBook changed to the same as rustdoc's, so we change some links back.
~~~This isn't quite ready yet; it's [depending on a PR of mine to mdBook](https://github.com/azerupi/mdBook/pull/209). After that's released, this should be the last of these kinds of shenanigans~~~ 😄
This is good to go 😄
