Do not run outer setup part of benchmarks multiple times to fix issue 20142
Fix#20142
This is my first real rust code, so I expect the quality is quite bad. Please let me know in which ways it is horrible and I'll fix it.
Previously the whole benchmark function was rerun many times, but with this change, only the callback passed to iter is rerun. This improves performances by saving benchmark startup time. The setup used to be called a minimum of 101 times, and now only runs once.
I wasn't sure exactly what should be done for the case where iter is never called, so I left a FIXME for that: currently it does not error, and I added tests to cover that.
I have left the algorithm and statistics unchanged: I don't like how the minimum number of runs is 301 (that's bad for very slow benchmarks) but I consider such changes out of scope for this fix.
rustbuild: Implement DESTDIR support
This commit primarily starts supporting the `DESTDIR` environment variable like
the old build system. Along the way this brings `config.toml` up to date with
support in `config.mk` with install options supported.
Closes#38441
UTF-8 validation: Compute block end upfront
Simplify the conditional used for ensuring that the whole word loop is
only used if there are at least two whole words left to read.
This makes the function slightly smaller and simpler, a 0-5% reduction
in runtime for various test cases.
std: Ignore close_read_wakes_up on Windows
It looks like in practice at least this test will not pass on Windows.
Empirically it is prone to blocking forever, presumably because a call to
`shutdown` doesn't actually wake up other threads on Windows.
We don't document this as a guarantee for `shutdown`, nor do we internally rely
on it. This test originated in a time long since passed when it was leveraged
for canceling I/O, but nowadays there's nothing fancy happening in the standard
library so it's not really a productive test anyway, hence just ignoring it on
Windows.
Closes#31657
resolve: clean up the semantics of `self` in an import list
Change `self` in an import list `use foo::bar::{self, ...};` to import `bar` only in the type namespace. Today, `bar` is imported in every namespace in which `foo::bar` is defined.
This is a [breaking-change], see https://github.com/rust-lang/rust/issues/38293#issue-194817974 for examples of code that would break.
Fixes#38293.
r? @nrc
fix function arguments in constant promotion
we can't create the target block until *after* we promote the arguments - otherwise the arguments will be promoted into the target block. oops.
Fixes#38985.
This is a regression introduced in the beta-nominated #38833, so beta-nominating this one too (sorry @brson).
r? @eddyb
rustbuild: Don't enable debuginfo in rustc
In #37280 we enabled line number debugging information in release artifacts,
primarily to close out #36452 where debugging information was critical for MSVC
builds of Rust to be useful in production. This commit, however, apparently had
some unfortunate side effects.
Namely it was noticed in #37477 that if `RUST_BACKTRACE=1` was set then any
compiler error would take a very long time for the compiler to exit. The cause
of the problem here was somewhat deep:
* For all compiler errors, the compiler will `panic!` with a known value. This
tears down the main compiler thread and allows cleaning up all the various
resources. By default, however, this panic output is suppressed for "normal"
compiler errors.
* When `RUST_BACKTRACE=1` was set this caused every compiler error to generate a
backtrace.
* The libbacktrace library hits a pathological case where it spends a very long
time in its custom allocation function, `backtrace_alloc`, because the
compiler has so much debugging information. More information about this can be
found in #29293 with a summary at the end of #37477.
To solve this problem this commit simply removes debuginfo from the compiler but
not from the standard library. This should allow us to keep #36452 closed while
also closing #37477. I've measured the difference to be orders of magnitude
faster than it was before, so we should see a much quicker time-to-exit after a
compile error when `RUST_BACKTRACE=1` is set.
Closes#37477Closes#37571
we can't create the target block until *after* we promote the arguments
- otherwise the arguments will be promoted into the target block. oops.
Fixes#38985.
Teach diagnostics to correct margin of multiline messages
Make the suggestion list have a correct padding:
```
error[E0308]: mismatched types
--> file.rs:3:20
|
3 | let x: usize = "";
| ^^ expected usize, found reference
|
= note: expected type `usize`
= note: found type `&'static str`
= help: here are some functions which might fulfill your needs:
- .len()
- .foo()
- .bar()
```
In #37280 we enabled line number debugging information in release artifacts,
primarily to close out #36452 where debugging information was critical for MSVC
builds of Rust to be useful in production. This commit, however, apparently had
some unfortunate side effects.
Namely it was noticed in #37477 that if `RUST_BACKTRACE=1` was set then any
compiler error would take a very long time for the compiler to exit. The cause
of the problem here was somewhat deep:
* For all compiler errors, the compiler will `panic!` with a known value. This
tears down the main compiler thread and allows cleaning up all the various
resources. By default, however, this panic output is suppressed for "normal"
compiler errors.
* When `RUST_BACKTRACE=1` was set this caused every compiler error to generate a
backtrace.
* The libbacktrace library hits a pathological case where it spends a very long
time in its custom allocation function, `backtrace_alloc`, because the
compiler has so much debugging information. More information about this can be
found in #29293 with a summary at the end of #37477.
To solve this problem this commit simply removes debuginfo from the compiler but
not from the standard library. This should allow us to keep #36452 closed while
also closing #37477. I've measured the difference to be orders of magnitude
faster than it was before, so we should see a much quicker time-to-exit after a
compile error when `RUST_BACKTRACE=1` is set.
Closes#37477Closes#37571
Use little-endian encoding for Blake2 hashing on all architectures
Like many hash functions, the blake2 hash is mathematically defined on
a sequence of 64-bit words. As Rust's hash interface operates on
sequences of octets, some encoding must be used to bridge that
difference.
The Blake2 RFC (RFC 7693) specifies that:
```
Byte (octet) streams are interpreted as words in little-endian order,
with the least-significant byte first.
```
So use that encoding consistently.
Fixes#38891.
Beta-nominating since this is a regression since 1.15.
r? @michaelwoerister
Implement `iter::Sum` and `iter::Product` for `Result`
This introduces a private iterator adapter `ResultShunt`, which allows
treating an iterator of `Result<T, E>` as an iterator of `T`.
Improved rustdoc rendering for unstable features
This replaces "unstable" with "this is an experimental API", and uses a `<details>` tag to expand to the reason.
The `<details>` tag renders as a regular div (with the details show) on browsers which don't support it, On browsers which do support it, it shows only the summary line with an expandy-arrow next to it, and on clicking it the details will turn up below it.
This is somewhat a strawman proposal. The main issue is that we need to improve our messaging around unstable APIs. Since they turn up in the docs, we should be clearer that they are experimental (and perhaps add something about nightly-only). I'm making this PR to kickstart discussion on this.
Example rendering: http://manishearth.github.io/rust-internals-docs/std/io/trait.Read.html#method.chars
<img width="375" alt="screen shot 2017-01-04 at 10 15 37 pm" src="https://cloud.githubusercontent.com/assets/1617736/21670712/5a96c7de-d2cb-11e6-86a6-87f70818d634.png">
expands to
<img width="799" alt="screen shot 2017-01-04 at 10 15 43 pm" src="https://cloud.githubusercontent.com/assets/1617736/21670714/5db88bb4-d2cb-11e6-8fcc-5cf11d198b75.png">
cc @steveklabnik @jdub
Like many hash functions, the blake2 hash is mathematically defined on
a sequence of 64-bit words. As Rust's hash interface operates on
sequences of octets, some encoding must be used to bridge that
difference.
The Blake2 RFC (RFC 7693) specifies that:
Byte (octet) streams are interpreted as words in little-endian order,
with the least-significant byte first.
So use that encoding consistently.
Fixes#38891.
Update vec.rs
Add a warning not to convert char* from c to Vec<u8> (I thought you could until I asked on irc).
Reasoning is that it will help people avoid an error that could cause crashes and undefined behaviour. Only drawback is that it could confuse someone not familiar with C, but beginners are unlikely to be using this function anyway.
std: Remove unused objects from compiler-builtins
We don't actually use trampoline_setup.c and all the `*tf3` business
seems related to f80/f128 business. Specifically this'll fix some
warnings showing up during builds on OSX.
book: use abort() over loop {} for panic
Due to #28728 `loop {}` is very risky and can lead to fun debugging experiences such as #38136. Besides, aborting is probably better behavior than an infinite loop.
r? @steveklabnik
Remove destructor-related restrictions from unions
They don't have drop glue.
This doesn't fix the rvalue promotion issues when trying to do things like `static FOO: NoDrop<Bar> = NoDrop {inner: Bar}`. I'm not sure if we should fix that.
Don't restrict docs in compiler-docs mode
Search is broken without this. We want all crates to be included in compiler-docs mode. This was changed in https://github.com/rust-lang/rust/pull/38858, this PR brings that functionality back in compiler-docs mode.
Avoid large number of stage 0 warnings about --no-stack-check
```
....
rustc: x86_64-pc-windows-gnu/stage0/lib/rustlib/x86_64-pc-windows-gnu/lib/libstd
warning: the --no-stack-check flag is deprecated and does nothing
rustc: x86_64-pc-windows-gnu/stage0/lib/rustlib/x86_64-pc-windows-gnu/lib/libgetopts
warning: the --no-stack-check flag is deprecated and does nothing
rustc: x86_64-pc-windows-gnu/stage0/lib/rustlib/x86_64-pc-windows-gnu/lib/libterm
warning: the --no-stack-check flag is deprecated and does nothing
rustc: x86_64-pc-windows-gnu/stage0/lib/rustlib/x86_64-pc-windows-gnu/lib/liblog
warning: the --no-stack-check flag is deprecated and does nothing
....
```
r? @alexcrichton
std: Add a nonblocking `Child::try_wait` method
This commit adds a new method to the `Child` type in the `std::process` module
called `try_wait`. This method is the same as `wait` except that it will not
block the calling thread and instead only attempt to collect the exit status. On
Unix this means that we call `waitpid` with the `WNOHANG` flag and on Windows it
just means that we pass a 0 timeout to `WaitForSingleObject`.
Currently it's possible to build this method out of tree, but it's unfortunately
tricky to do so. Specifically on Unix you essentially lose ownership of the pid
for the process once a call to `waitpid` has succeeded. Although `Child` tracks
this state internally to be resilient to multiple calls to `wait` or a `kill`
after a successful wait, if the child is waited on externally then the state
inside of `Child` is not updated. This means that external implementations of
this method must be extra careful to essentially not use a `Child`'s methods
after a call to `waitpid` has succeeded (even in a nonblocking fashion).
By adding this functionality to the standard library it should help canonicalize
these external implementations and ensure they can continue to robustly reuse
the `Child` type from the standard library without worrying about pid ownership.
