When building for AArch64/Linux, __morestack ends up in the .note.GNU-stack section,
which causes missing references for the linker. By using the func/endfunc macros
from macros.S we get __morestack right to .text (and a bit more on the side).
In general, it's undesirable to have read_to_end use a buffer with uninitialized memory, as that could lead to undefined behaviour in the event of a bad Read implementation. Since we control the implementations of Read for Stdin and File, however, it should be okay for us to specialise them to improve performance. This PR is to do that!
Adds some unsafe code to deal with creating the buffers. Since the read_to_end function needed to be used from the io and fs crates, I moved it into a newly-created sys::common::io module. Alternatively we could expose the new read_to_end functions to allow people to create their own read_to_end implementations for code they trust.
Benchmarks:
Read a 2.5MB file:
sys_common::io::tests::bench_init_file ... bench: 27,473,317 ns/iter (+/- 2,490,767)
sys_common::io::tests::bench_uninit_file ... bench: 25,611,793 ns/iter (+/- 2,137,387)
Read a buffer full of constant values
sys_common::io::tests::bench_uninitialized ... bench: 12,877,645 ns/iter (+/- 931,025)
sys_common::io::tests::bench_zeroed ... bench: 18,581,082 ns/iter (+/- 1,541,108)
So, approx a 7% speedup for file reading, which I think is worthwhile.
The error now looks like this:
```
<anon>:4:9: 4:10 error: use of moved value: `x` [E0382]
<anon>:4 foo(x);
^
<anon>:3:9: 3:10 note: `x` moved here because it has type `Box<i32>`, which is moved by default
<anon>:3 let y = x;
^
<anon>:3:9: 3:10 help: use `ref` to take a reference instead:
<anon>: let ref y = x;
```
This has travis build LLVM and rustc up to stage1, but not run any tests. It seems wasteful to have the ultimate might of travis running on every PR just to check for whitespace errors. This is a pure subset of the bootstrap, so it shouldn't ever spuriously break.
`make tidy` still runs first, so we still get \"fast errors\" on bad style. However once make tidy passes, the build will simply keep running to try to make rustc. `tidy` takes ~3 mins to complete, so if your build runs longer you can be confident we've gone on to build LLVM/rustc. In principle this is configured to use ccache (it shows up in the build logs as uploaded/downloaded), but I found no actual performance changes in using it.
Maybe someone at @travis-ci knows what's up with that.
For reference, here is a successful build with ccache enabled: https://travis-ci.org/Gankro/rust/builds/70821237
and one without: https://travis-ci.org/Gankro/rust/builds/70812814
Builds seem to take about 41mins regardless.
r? @alexcrichton
This PR fixes a snippet of code on the error handling chapter of \"The Rust Programming Language\".
//cc @steveklabnik
The docs state that trying to compile the snippet will yield the following error:
```bash
anon>:13:5: 20:6 error: non-exhaustive patterns: `_` not covered [E0004]
```
But instead the error received is:
```bash
<anon>:22:46: 22:56 error: unresolved name `NewRelease`
<anon>:22 std::io::println(descriptive_probability(NewRelease));
^~~~~~~~~~
<anon>:22:5: 22:21 error: unresolved name `std::io::println`
<anon>:22 std::io::println(descriptive_probability(NewRelease));
^~~~~~~~~~~~~~~~
error: aborting due to 2 previous errors
playpen: application terminated with error code 101
```
After applying this PR the expected error is returned:
```bash
anon>:13:5: 20:6 error: non-exhaustive patterns: `_` not covered [E0004]
<anon>:13 match probability(&event) {
<anon>:14 1.00 => \"certain\",
<anon>:15 0.00 => \"impossible\",
<anon>:16 0.00 ... 0.25 => \"very unlikely\",
<anon>:17 0.25 ... 0.50 => \"unlikely\",
<anon>:18 0.50 ... 0.75 => \"likely\",
...
<anon>:13:5: 20:6 help: see the detailed explanation for E0004
error: aborting due to previous error
```
A merge in #24523 broke the explanation for E0303. This commit restores the previous version and also removes an erroneous `&` (which had nothing to do with the merge).
Yet another attempt to make the prose on the std crate page
clearer and more informative.
This does a lot of things: tightens up the opening, adds useful links
(including a link to the search bar), offers guidance on how to use
the docs, and expands the prelude docs as a useful newbie entrypoint.
r? @steveklabnik cc @aturon
This help people using keyboard navigation or with disabilities to
easily browse through pagination. For example, in Vimium, a reader can
do `[[` or `]]` to browse through the pages.
Expands E0201 to be used for any duplicate associated items, not just duplicate
methods/functions. It also correctly detects when two different kinds of items
(like a constant and a method) have the same name.
Fixes#23969.
Tidy is still run first for failing fast on the easy stuff.
To accomplish this we have travis actually persist ccache across builds. This
has LLVM built within 6 minutes, and all of stage1 built within 18.
Caching should work on fresh PRs (cache acquired from the master branch).
Because all we persist is ccache, there is minimal danger of persisting corrupt
build state.
I had to mangle `configure` a bit to make --enable-ccache work when custom
compilers are provide via CC and CXX.
and deprecate/remove unsigned_negation lint.
This is useful to avoid causing breaking changes in case #![deny(unknown_lints)]
is used and lint is removed.
