Using `generic` as the target cpu limits the generated code to the bare basics for the arch, while we can probably assume that we'll actually be running on somewhat modern hardware. This updates the default target CPUs for the x86 and x86_64 archs to match clang's behaviour.
Refs #20777
In preparation for the I/O rejuvination of the standard library, this commit
renames the current `io` module to `old_io` in order to make room for the new
I/O modules. It is expected that the I/O RFCs will land incrementally over time
instead of all at once, and this provides a fresh clean path for new modules to
enter into as well as guaranteeing that all old infrastructure will remain in
place for some time.
As each `old_io` module is replaced it will be deprecated in-place for new
structures in `std::{io, fs, net}` (as appropriate).
This commit does *not* leave a reexport of `old_io as io` as the deprecation
lint does not currently warn on this form of use. This is quite a large breaking
change for all imports in existing code, but all functionality is retained
precisely as-is and path statements simply need to be renamed from `io` to
`old_io`.
[breaking-change]
In preparation for upcoming changes to the `Writer` trait (soon to be called
`Write`) this commit renames the current `write` method to `write_all` to match
the semantics of the upcoming `write_all` method. The `write` method will be
repurposed to return a `usize` indicating how much data was written which
differs from the current `write` semantics. In order to head off as much
unintended breakage as possible, the method is being deprecated now in favor of
a new name.
[breaking-change]
In preparation for the I/O rejuvination of the standard library, this commit
renames the current `io` module to `old_io` in order to make room for the new
I/O modules. It is expected that the I/O RFCs will land incrementally over time
instead of all at once, and this provides a fresh clean path for new modules to
enter into as well as guaranteeing that all old infrastructure will remain in
place for some time.
As each `old_io` module is replaced it will be deprecated in-place for new
structures in `std::{io, fs, net}` (as appropriate).
This commit does *not* leave a reexport of `old_io as io` as the deprecation
lint does not currently warn on this form of use. This is quite a large breaking
change for all imports in existing code, but all functionality is retained
precisely as-is and path statements simply need to be renamed from `io` to
`old_io`.
[breaking-change]
Before ca07e256f62f772d14c42f41af46f2aeacc54983, LLVM's AArch64FastISel
had a sign (and zero?) extension bug. Until rustc gets its LLVM past
that commit, the way of workaround is to pass an option to LLVM that
forces the disabling of FastISel (which would normally kick in for -O0).
Fixes#21627
This ends up propagating all the way out to the output of dep-info which then
makes Cargo think that files are not existent (it thinks the files have quotes
in their name) when they in fact do.
Don't reallocate when capacity is already equal to length
`Vec::shrink_to_fit()` may be called on vectors that are already the
correct length. Calling out to `reallocate()` in this case is a bad idea
because there is no guarantee that `reallocate()` won't allocate a new
buffer anyway, and based on performance seen in external benchmarks, it
seems likely that it is in fact reallocating a new buffer.
Before:
test string::tests::bench_exact_size_shrink_to_fit ... bench: 45 ns/iter (+/- 2)
After:
test string::tests::bench_exact_size_shrink_to_fit ... bench: 26 ns/iter (+/- 1)
Limiting ourselves to a generic x86 instruction set doesn't seem useful.
Both users running those systems on original i386 hardware might as well
manually specify a target cpu ;-)
Clang uses the same default.
There are some explicit Send/Sync implementations for Window's types
that don't exist in Unix. While the end result will be the same, I
believe it's clearer if we keep the explicit implementations consistent
by making the os-specific types Send/Sync where needed and possible.
This commit addresses tcp. Existing differences below:
src/libstd/sys/unix/tcp.rs
unsafe impl Sync for TcpListener {}
unsafe impl Sync for AcceptorInner {}
src/libstd/sys/windows/tcp.rs
unsafe impl Send for Event {}
unsafe impl Sync for Event {}
unsafe impl Send for TcpListener {}
unsafe impl Sync for TcpListener {}
unsafe impl Send for TcpAcceptor {}
unsafe impl Sync for TcpAcceptor {}
unsafe impl Send for AcceptorInner {}
unsafe impl Sync for AcceptorInner {}
There are some explicit Send/Sync implementations for Window's types
that don't exist in Unix. While the end result will be the same, I
believe it's clearer if we keep the explicit implementations consistent
by making the os-specific types Send/Sync where needed and possible.
This commit addresses pipe
src/libstd/sys/unix/pipe.rs
unsafe impl Send for UnixListener {}
unsafe impl Sync for UnixListener {}
src/libstd/sys/windows/pipe.rs
unsafe impl Send for UnixStream {}
unsafe impl Sync for UnixStream {}
unsafe impl Send for UnixListener {}
unsafe impl Sync for UnixListener {}
unsafe impl Send for UnixAcceptor {}
unsafe impl Sync for UnixAcceptor {}
unsafe impl Send for AcceptorState {}
unsafe impl Sync for AcceptorState {}
I'm beginning to suspect it's impossible to avoid accidentally writing
`#[deriving]` at least once in every program, and it results in
non-intuitive error messages: "Foo doesn't have any method in scope
`clone`" despite there being a `#[deriv...(Clone)]` attribute!
Also, lots of documentation around the internet uses `#[deriving]` so
providing this guidance is very helpful (lots of people ask in #rust
about this error).
the syntax of 'case' is:
`case word in [[(] pattern [| pattern] ...) list ;; ] ... esac`
`list` don't have to issue `break`. `break` is normally used to exit a
`for`, `until` or `while` loop.
