allow RUST_BACKTRACE=0 to act as if unset
**UPDATE:** `RUST_BACKTRACE=0` to act as if the env. var is unset! (now `0` is what `disabled` was for, below)
When RUST_BACKTRACE is set to "disabled" then this acts as if the env. var is unset. So, either make sure `RUST_BACKTRACE` is not set OR set it to `disabled` to achieve the same effect.
Sample usage:
```bash
$ rustc -o /tmp/a.out -- <(echo 'fn main(){ panic!() }') && RUST_BACKTRACE=disabled /tmp/a.out
!! executing '/home/zazdxscf/build/1nonpkgs/rust/rust//x86_64-unknown-linux-gnu/stage2/bin//rustc' with args: '-o /tmp/a.out -- /dev/fd/63'
thread '<main>' panicked at 'explicit panic', /dev/fd/63:1
note: Run with `RUST_BACKTRACE=1` for a backtrace.
$ rustc -o /tmp/a.out -- <(echo 'fn main(){ panic!() }') && RUST_BACKTRACE=1 /tmp/a.out
!! executing '/home/zazdxscf/build/1nonpkgs/rust/rust//x86_64-unknown-linux-gnu/stage2/bin//rustc' with args: '-o /tmp/a.out -- /dev/fd/63'
thread '<main>' panicked at 'explicit panic', /dev/fd/63:1
stack backtrace:
1: 0x55709e8148c0 - sys::backtrace::tracing:👿:write::h140f24a0cfc189b98Ru
2: 0x55709e816a5b - panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::closure.45165
3: 0x55709e8166e8 - panicking::default_hook::hed419823688cb82aXoA
4: 0x55709e810fff - sys_common::unwind::begin_unwind_inner::hbb9642f6e212d56fmHt
5: 0x55709e810513 - sys_common::unwind::begin_unwind::h16232867470678019594
6: 0x55709e810489 - main::hb524f9576270962feaa
7: 0x55709e816314 - sys_common::unwind::try::try_fn::h1274188004693518534
8: 0x55709e813dfb - __rust_try
9: 0x55709e815dab - rt::lang_start::h712b1cd650781872ahA
10: 0x55709e810679 - main
11: 0x7efd1026859f - __libc_start_main
12: 0x55709e810348 - _start
13: 0x0 - <unknown>
```
Some programs(eg. [vim's syntactic](https://github.com/scrooloose/syntastic) used by [rust.vim](https://github.com/rust-lang/rust.vim)) cannot unset the env. var RUST_BACKTRACE if it's already set(eg. in .bashrc) but [they can set it to some value](cb5533e159/system/Z575/OSes/gentoo/on_baremetal/filesystem_now/gentoo/home/zazdxscf/build/1nonpkgs/rust.vim/upd (L17)), and I needed to ensure the env. var is unset in order to avoid this issue: https://github.com/rust-lang/rust/issues/29293
**EDIT:** Sample usage 2:
```bash
$ export RUST_BACKTRACE=1
$ rustc -o /tmp/a.out -- <(echo 'fn main(){ panic!() }') && /tmp/a.out
!! executing '/home/zazdxscf/build/1nonpkgs/rust/rust//x86_64-unknown-linux-gnu/stage2/bin//rustc' with args: '-o /tmp/a.out -- /dev/fd/63'
thread '<main>' panicked at 'explicit panic', /dev/fd/63:1
stack backtrace:
1: 0x55c2696738c0 - sys::backtrace::tracing:👿:write::h140f24a0cfc189b98Ru
2: 0x55c269675a5b - panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::closure.45165
3: 0x55c2696756e8 - panicking::default_hook::hed419823688cb82aXoA
4: 0x55c26966ffff - sys_common::unwind::begin_unwind_inner::hbb9642f6e212d56fmHt
5: 0x55c26966f513 - sys_common::unwind::begin_unwind::h16023941661074805588
6: 0x55c26966f489 - main::hb524f9576270962feaa
7: 0x55c269675314 - sys_common::unwind::try::try_fn::h1274188004693518534
8: 0x55c269672dfb - __rust_try
9: 0x55c269674dab - rt::lang_start::h712b1cd650781872ahA
10: 0x55c26966f679 - main
11: 0x7f593d58459f - __libc_start_main
12: 0x55c26966f348 - _start
13: 0x0 - <unknown>
$ rustc -o /tmp/a.out -- <(echo 'fn main(){ panic!() }') && RUST_BACKTRACE=disabled /tmp/a.out
!! executing '/home/zazdxscf/build/1nonpkgs/rust/rust//x86_64-unknown-linux-gnu/stage2/bin//rustc' with args: '-o /tmp/a.out -- /dev/fd/63'
thread '<main>' panicked at 'explicit panic', /dev/fd/63:1
note: Run with `RUST_BACKTRACE=1` for a backtrace.
```
/# This is a combination of 16 commits.
/# The first commit's message is:
allow RUST_BACKTRACE=disabled to act as if unset
When RUST_BACKTRACE is set to "disabled" then this acts as if the env.
var is unset.
/# This is the 2nd commit message:
case insensitive "DiSaBLeD" RUST_BACKTRACE value
previously it expected a lowercase "disabled" to treat the env. var as
unset
/# This is the 3rd commit message:
RUST_BACKTRACE=0 acts as if unset
previously RUST_BACKTRACE=disabled was doing the same thing
/# This is the 4th commit message:
RUST_BACKTRACE=0|n|no|off acts as if unset
previously only RUST_BACKTRACE=0 acted as if RUST_BACKTRACE was unset
Now added more options (case-insensitive): 'n','no' and 'off'
eg. RUST_BACKTRACE=oFF
/# This is the 5th commit message:
DRY on the value of 2
DRY=don't repeat yourself
Because having to remember to keep the two places of '2' in sync is not
ideal, even though this is a simple enough case.
/# This is the 6th commit message:
Revert "DRY on the value of 2"
This reverts commit 95a0479d5cf72a2b2d9d21ec0bed2823ed213fef.
Nevermind this DRY on 2, because we already have a RY on 1,
besides the code is less readable this way...
/# This is the 7th commit message:
attempt to document unsetting RUST_BACKTRACE
/# This is the 8th commit message:
curb allocations when checking for RUST_BACKTRACE
this means we don't check for case-insensitivity anymore
/# This is the 9th commit message:
as decided, RUST_BACKTRACE=0 turns off backtrace
/# This is the 10th commit message:
RUST_TEST_NOCAPTURE=0 acts as if unset
(that is, capture is on)
Any other value acts as if nocapture is enabled (that is, capture is off)
/# This is the 11th commit message:
update other RUST_TEST_NOCAPTURE occurrences
apparently only one place needs updating
/# This is the 12th commit message:
update RUST_BACKTRACE in man page
/# This is the 13th commit message:
handle an occurrence of RUST_BACKTRACE
/# This is the 14th commit message:
ensure consistency with new rules for backtrace
/# This is the 15th commit message:
a more concise comment for RUST_TEST_NOCAPTURE
/# This is the 16th commit message:
update RUST_TEST_NOCAPTURE in man page
Remove no longer necessary coercions to fn pointer types.
Originally added in 8fe9e4dff6.
Everything appears to build fine without the coercions, so they can
presumably be removed.
style: Use `iter` for IntoIterator parameter names
This commit standardizes the codebase on `iter` for parameters with
IntoIterator bounds.
Previously about 40% of IntoIterator parameters were named `iterable`,
with most of the rest being named `iter`. There was a single place where
it was named `iterator`.
This commit standardizes the codebase on `iter` for parameters with
IntoIterator bounds.
Previously about 40% of IntoIterator parameters were named `iterable`,
with most of the rest being named `iter`. There was a single place where
it was named `iterator`.
Fix missing console output in `Barrier` example
The `println!` calls in the previous version were never shown (at least
not in the playpen) because the main thread is finished before all the
spawned child threads were synchronized. This commit adds a join for
each thread handle to wait in the main thread until all child threads
are finished.
r? @steveklabnik
This adds checks to ensure that:
* link anchors refer to existing id's on the target page
* id's are unique within an html document
* page redirects are valid
std: Rewrite Once with poisoning
This commit rewrites the `std::sync::Once` primitive with poisoning in mind in
light of #31688. Currently a panic in the initialization closure will cause
future initialization closures to run, but the purpose of a Once is usually to
initialize some global state so it's highly likely that the global state is
corrupt if a panic happened. The same strategy of a mutex is taken where a panic
is propagated by default.
A new API, `call_once_force`, was added to subvert panics like is available on
Mutex as well (for when panicking is handled internally).
Adding this support was a significant enough change to the implementation that
it was just completely rewritten from scratch, primarily to avoid using a
`StaticMutex` which needs to have `destroy()` called on it at some point (a pain
to do).
Closes#31688
This commit rewrites the `std::sync::Once` primitive with poisoning in mind in
light of #31688. Currently a panic in the initialization closure will cause
future initialization closures to run, but the purpose of a Once is usually to
initialize some global state so it's highly likely that the global state is
corrupt if a panic happened. The same strategy of a mutex is taken where a panic
is propagated by default.
A new API, `call_once_force`, was added to subvert panics like is available on
Mutex as well (for when panicking is handled internally).
Adding this support was a significant enough change to the implementation that
it was just completely rewritten from scratch, primarily to avoid using a
`StaticMutex` which needs to have `destroy()` called on it at some point (a pain
to do).
Closes#31688
The `println!` calls in the previous version were never shown (at least
not in the playpen) because the main thread is finished before all the
spawned child threads were synchronized. This commit adds a join for
each thread handle to wait in the main thread until all child threads
are finished.
Fix unsound behaviour with null characters in thread names (issue #32475)
Previously, the thread name (&str) was converted to a CString in the
new thread, but outside unwind::try, causing a panic to continue into FFI.
This patch changes that behaviour, so that the panic instead happens
in the parent thread (where panic infrastructure is properly set up),
not the new thread.
This could potentially be a breaking change for architectures who don't
support thread names.
Restrict constants in patterns
This implements [RFC 1445](https://github.com/rust-lang/rfcs/blob/master/text/1445-restrict-constants-in-patterns.md). The primary change is to limit the types of constants used in patterns to those that *derive* `Eq` (note that implementing `Eq` is not sufficient). This has two main effects:
1. Floating point constants are linted, and will eventually be disallowed. This is because floating point constants do not implement `Eq` but only `PartialEq`. This check replaces the existing special case code that aimed to detect the use of `NaN`.
2. Structs and enums must derive `Eq` to be usable within a match.
This is a [breaking-change]: if you encounter a problem, you are most likely using a constant in an expression where the type of the constant is some struct that does not currently implement
`Eq`. Something like the following:
```rust
struct SomeType { ... }
const SOME_CONST: SomeType = ...;
match foo {
SOME_CONST => ...
}
```
The easiest and most future compatible fix is to annotate the type in question with `#[derive(Eq)]` (note that merely *implementing* `Eq` is not enough, it must be *derived*):
```rust
struct SomeType { ... }
const SOME_CONST: SomeType = ...;
match foo {
SOME_CONST => ...
}
```
Another good option is to rewrite the match arm to use an `if` condition (this is also particularly good for floating point types, which implement `PartialEq` but not `Eq`):
```rust
match foo {
c if c == SOME_CONST => ...
}
```
Finally, a third alternative is to tag the type with `#[structural_match]`; but this is not recommended, as the attribute is never expected to be stabilized. Please see RFC #1445 for more details.
cc https://github.com/rust-lang/rust/issues/31434
r? @pnkfelix
std: Link to gcc_s on NetBSD
Currently the nightlies we're producing fail when linking some C code into a
Rust application with the error message:
libgcc_s.so.1: error adding symbols: DSO missing from command line
By linking `gcc_s` instead of `gcc` this error goes away. I haven't tested this
on NetBSD itself, but should help get the Linux cross-compile image moreso up
and working!
Previously, the thread name (&str) was converted to a CString in the
new thread, but outside unwind::try, causing a panic to continue into FFI.
This patch changes that behaviour, so that the panic instead happens
in the parent thread (where panic infrastructure is properly set up),
not the new thread.
This could potentially be a breaking change for architectures who don't
support thread names.
Signed-off-by: David Henningsson <diwic@ubuntu.com>
std: Store flowinfo/scope_id in host byte order
Apparently these aren't supposed to be stored in network byte order, so doing so
ends up causing failures when it would otherwise succeed when stored in the host
byte order.
Closes#32424
convert 99.9% of `try!`s to `?`s
The first commit is an automated conversion using the [untry] tool and the following command:
```
$ find -name '*.rs' -type f | xargs untry
```
at the root of the Rust repo.
[untry]: https://github.com/japaric/untry
cc @rust-lang/lang @alexcrichton @brson
