Auto merge of #50135 - matklad:update-cargo, r=kennytm
Update Cargo
Some noteble changes:
* ~~regression fix: https://github.com/rust-lang/cargo/pull/5390~~
* ~~potentially breaking bug-fix: https://github.com/rust-lang/cargo/pull/5389~~
* ~~Cargo now caches the result of `rustc -vV`. It checks `rustc` binary
mtime and rustup toolchain settings, so it should probably "just work"
with rustbuild.~~
Auto merge of #49896 - SimonSapin:inherent, r=alexcrichton
Add inherent methods in libcore for [T], [u8], str, f32, and f64
# Background
Primitive types are defined by the language, they don’t have a type definition like `pub struct Foo { … }` in any crate. So they don’t “belong” to any crate as far as `impl` coherence is concerned, and on principle no crate would be able to define inherent methods for them, without a trait. Since we want these types to have inherent methods anyway, the standard library (with cooperation from the compiler) bends this rule with code like [`#[lang = "u8"] impl u8 { /*…*/ }`](https://github.com/rust-lang/rust/blob/1.25.0/src/libcore/num/mod.rs#L2244-L2245). The `#[lang]` attribute is permanently-unstable and never intended to be used outside of the standard library.
Each lang item can only be defined once. Before this PR there is one impl-coherence-rule-bending lang item per primitive type (plus one for `[u8]`, which overlaps with `[T]`). And so one `impl` block each. These blocks for `str`, `[T]` and `[u8]` are in liballoc rather than libcore because *some* of the methods (like `<[T]>::to_vec(&self) -> Vec<T> where T: Clone`) need a global memory allocator which we don’t want to make a requirement in libcore. Similarly, `impl f32` and `impl f64` are in libstd because some of the methods are based on FFI calls to C’s `libm` and we want, as much as possible, libcore not to require “runtime support”.
In libcore, the methods of `str` and `[T]` that don’t allocate are made available through two **unstable traits** `StrExt` and `SliceExt` (so the traits can’t be *named* by programs on the Stable release channel) that have **stable methods** and are re-exported in the libcore prelude (so that programs on Stable can *call* these methods anyway). Non-allocating `[u8]` methods are not available in libcore: https://github.com/rust-lang/rust/issues/45803. Some `f32` and `f64` methods are in an unstable `core::num::Float` trait with stable methods, but that one is **not in the libcore prelude**. (So as far as Stable programs are concerns it doesn’t exist, and I don’t know what the point was to mark these methods `#[stable]`.)
https://github.com/rust-lang/rust/issues/32110 is the tracking issue for these unstable traits.
# High-level proposal
Since the standard library is already bending the rules, why not bend them *a little more*? By defining a few additional lang items, the compiler can allow the standard library to have *two* `impl` blocks (in different crates) for some primitive types.
The `StrExt` and `SliceExt` traits still exist for now so that we can bootstrap from a previous-version compiler that doesn’t have these lang items yet, but they can be removed in next release cycle. (`Float` is used internally and needs to be public for libcore unit tests, but was already `#[doc(hidden)]`.) I don’t know if https://github.com/rust-lang/rust/issues/32110 should be closed by this PR, or only when the traits are entirely removed after we make a new bootstrap compiler.
# Float methods
Among the methods of the `core::num::Float` trait, three are based on LLVM intrinsics: `abs`, `signum`, and `powi`. PR https://github.com/rust-lang/rust/pull/27823 “Remove dependencies on libm functions from libcore” moved a bunch of `core::num::Float` methods back to libstd, but left these three behind. However they aren’t specifically discussed in the PR thread. The `compiler_builtins` crate defines `__powisf2` and `__powidf2` functions that look like implementations of `powi`, but I couldn’t find a connection with the `llvm.powi.f32` and `llvm.powi.f32` intrinsics by grepping through LLVM’s code.
In discussion starting at https://github.com/rust-lang/rust/issues/32110#issuecomment-370647922 Alex says that we do not want methods in libcore that require “runtime support”, but it’s not clear whether that applies to these `abs`, `signum`, or `powi`. In doubt, I’ve **removed** them for the trait and moved them to inherent methods in libstd for now. We can move them back later (or in this PR) if we decide that’s appropriate.
# Change details
For users on the Stable release channel:
* I believe this PR does not make any breaking change
* Some methods for `[u8]`, `f32`, and `f64` are newly available to `#![no_std]` users (fixes https://github.com/rust-lang/rust/issues/45803)
* There should be no visible change for `std` users in terms of what programs compile or what their behavior is. (Only in compiler error messages, possibly.)
For Nightly users, additionally:
* The unstable `StrExt` and `SliceExt` traits are gone
* Their methods are now inherent methods of `str` and `[T]` (so only code that explicitly named the traits should be affected, not "normal" method calls)
* The `abs`, `signum` and `powi` methods of the `Float` trait are gone
* The `Float` trait’s unstable feature name changed to `float_internals` with no associated tracking issue, to reflect it being a permanently unstable implementation detail rather than a public API on a path to stabilization.
* Its remaining methods are now inherent methods of `f32` and `f64`.
-----
CC @rust-lang/libs for the API changes, @rust-lang/compiler for the new lang items
Auto merge of #50121 - pnkfelix:revert-stabilization-of-never-type-et-al, r=alexcrichton
Revert stabilization of never_type (!) et al
Fix #49691
I *think* this correctly adopts @nikomatsakis 's desired fix of:
* reverting stabilization of `!` and `TryFrom`, and
* returning to the previous fallback semantics (i.e. it is once again dependent on whether the crate has opted into `#[feature(never_type)]`,
* **without** attempting to put back in the previous future-proofing warnings regarding the change in fallback semantics.
(I'll be away from computers for a week starting now, so any updates to this PR should be either pushed into it, or someone else should adopt the task of polishing this fix and put up their own PR.)
Auto merge of #50039 - ExpHP:quick-50002, r=alexcrichton
smaller PR just to fix #50002
I pulled this out of #50010 to make it easier to backport to beta if necessary, considering that inclusive range syntax is stabilizing soon (?).
It fixes a bug in `<str>::index_mut` with `(..=end)` ranges (#50002), which prior to this fix was not only unusable but also UB in the cases where it "worked" (it gave improperly truncated UTF-8).
(not that I can imagine why anybody would *use* `<str>::index_mut`... but I'm not here to judge)
Auto merge of #50093 - alexcrichton:android-uwtable, r=michaelwoerister
rustc: Always emit `uwtable` on Android
Long ago (#40549) we enabled the `uwtable` attribute on Windows by default
(even with `-C panic=abort`) to allow unwinding binaries for [stack unwinding
information][winstack]. It looks like this same issue is [plaguing][arm1]
Gecko's Android platforms [as well][arm2]. This commit applies the same fix
as #40549 except that this time it's applied for all Android targets.
Generating a `-C panic=abort` binary for `armv7-linux-androideabi` before this
commit generated a number of `cantunwind` functions (detected with `readelf -u`)
but after this commit they all list appropriate unwind information.
Alex Crichton [Thu, 19 Apr 2018 22:17:34 +0000 (15:17 -0700)]
rustc: Always emit `uwtable` on Android
Long ago (#40549) we enabled the `uwtable` attribute on Windows by default
(even with `-C panic=abort`) to allow unwinding binaries for [stack unwinding
information][winstack]. It looks like this same issue is [plaguing][arm1]
Gecko's Android platforms [as well][arm2]. This commit applies the same fix
as #40549 except that this time it's applied for all Android targets.
Generating a `-C panic=abort` binary for `armv7-linux-androideabi` before this
commit generated a number of `cantunwind` functions (detected with `readelf -u`)
but after this commit they all list appropriate unwind information.
Auto merge of #50120 - alexcrichton:more-proc-macro-gates, r=petrochenkov
rustc: Tweak custom attribute capabilities
This commit starts to lay some groundwork for the stabilization of custom
attribute invocations and general procedural macros. It applies a number of
changes discussed on [internals] as well as a [recent issue][issue], namely:
* The path used to specify a custom attribute must be of length one and cannot
be a global path. This'll help future-proof us against any ambiguities and
give us more time to settle the precise syntax. In the meantime though a bare
identifier can be used and imported to invoke a custom attribute macro. A new
feature gate, `proc_macro_path_invoc`, was added to gate multi-segment paths
and absolute paths.
* The set of items which can be annotated by a custom procedural attribute has
been restricted. Statements, expressions, and modules are disallowed behind
two new feature gates: `proc_macro_expr` and `proc_macro_mod`.
* The input to procedural macro attributes has been restricted and adjusted.
Today an invocation like `#[foo(bar)]` will receive `(bar)` as the input token
stream, but after this PR it will only receive `bar` (the delimiters were
removed). Invocations like `#[foo]` are still allowed and will be invoked in
the same way as `#[foo()]`. This is a **breaking change** for all nightly
users as the syntax coming in to procedural macros will be tweaked slightly.
* Procedural macros (`foo!()` style) can only be expanded to item-like items by
default. A separate feature gate, `proc_macro_non_items`, is required to
expand to items like expressions, statements, etc.
* regression fix: https://github.com/rust-lang/cargo/pull/5390
* potentially breaking bug-fix: https://github.com/rust-lang/cargo/pull/5389
* Cargo now caches the result of `rustc -vV`. It checks `rustc` binary
mtime and rustup toolchain settings, so it should probably "just work"
with rustbuild.
Simon Sapin [Sun, 8 Apr 2018 08:09:52 +0000 (10:09 +0200)]
Add some f32 and f64 inherent methods in libcore
… previously in the unstable core::num::Float trait.
Per https://github.com/rust-lang/rust/issues/32110#issuecomment-379503183,
the `abs`, `signum`, and `powi` methods are *not* included for now
since they rely on LLVM intrinsics and we haven’t determined yet whether
those instrinsics lower to calls to libm functions on any platform.
Alex Crichton [Fri, 20 Apr 2018 14:50:39 +0000 (07:50 -0700)]
rustc: Tweak custom attribute capabilities
This commit starts to lay some groundwork for the stabilization of custom
attribute invocations and general procedural macros. It applies a number of
changes discussed on [internals] as well as a [recent issue][issue], namely:
* The path used to specify a custom attribute must be of length one and cannot
be a global path. This'll help future-proof us against any ambiguities and
give us more time to settle the precise syntax. In the meantime though a bare
identifier can be used and imported to invoke a custom attribute macro. A new
feature gate, `proc_macro_path_invoc`, was added to gate multi-segment paths
and absolute paths.
* The set of items which can be annotated by a custom procedural attribute has
been restricted. Statements, expressions, and modules are disallowed behind
two new feature gates: `proc_macro_expr` and `proc_macro_mod`.
* The input to procedural macro attributes has been restricted and adjusted.
Today an invocation like `#[foo(bar)]` will receive `(bar)` as the input token
stream, but after this PR it will only receive `bar` (the delimiters were
removed). Invocations like `#[foo]` are still allowed and will be invoked in
the same way as `#[foo()]`. This is a **breaking change** for all nightly
users as the syntax coming in to procedural macros will be tweaked slightly.
* Procedural macros (`foo!()` style) can only be expanded to item-like items by
default. A separate feature gate, `proc_macro_non_items`, is required to
expand to items like expressions, statements, etc.
Auto merge of #50088 - alexcrichton:std-tweaks, r=sfackler
Tweak some stabilizations in libstd
This commit tweaks a few stable APIs in the `beta` branch before they hit
stable. The `str::is_whitespace` and `str::is_alphanumeric` functions were
deleted (added in #49381, issue at #49657). The `and_modify` APIs added
in #44734 were altered to take a `FnOnce` closure rather than a `FnMut` closure.
Bring back old fallback semantics: Without feature(never_type), fallback to `()`, not `!`.
Note that this commit, since it is trying to be minimal in order to
ease backporting to the beta and release channels, does *not* include
the old future-proofing warnings that we used to have associated with
such fallback to `()`; see discussion at this comment:
Rollup merge of #50104 - mixi:libxml2-llvm, r=alexcrichton
Disable auto-detection of libxml2 when compiling llvm.
This broke cross-compiling rustc with internal llvm (with both the host and target being executable on the machine), because llvm's build system detected libxml2 on the host, therefore auto-enabled libxml2 support, but wouldn't compile as the target didn't have libxml2 installed.
Rollup merge of #50083 - alexcrichton:increase-wasm-stack, r=michaelwoerister
wasm: Increase default stack size to 1MB
This commit increases the dfeault stack size allocated to the
wasm32-unknown-unknown target to 1MB by default. Currently the default stack
size is one wasm page, or 64 kilobytes. This default stack is quite small and
has caused a stack overflow or two in the wild by accident.
The current "best practice" for fixing this is to pass `-Clink-args='-z
stack-size=$bigger'` but that's not great nor always easy to do. A default of
1MB matches more closely with other platforms where it's "pretty big" by
default.
Note that it was tested and if the users uses `-C link-args` to pass a custom
stack size that's still resepected as lld seems to take the first argument, and
where rustc is passing it will always be last.
Auto merge of #50062 - varkor:xpy-check-rustdoc, r=Mark-Simulacrum
Add rustdoc to x.py check
Modifying rustc can often cause errors in rustdoc, so it's useful to include it in the steps that are checked.
One thing that I was unsure about was when to call `clear_if_dirty` (both in this step, and in other steps in relation to this one) — we want to be sure rustdoc will always be rechecked after modifying previous steps — but does this belong in rustdoc, or the other steps?
Auto merge of #50052 - nnethercote:char_lit, r=Mark-Simulacrum
Avoid allocating when parsing \u{...} literals.
`char_lit` uses an allocation in order to ignore '_' chars in \u{...}
literals. This patch changes it to not do that by processing the chars
more directly.
This improves various rustc-perf benchmark measurements by up to 6%,
particularly regex, futures, clap, coercions, hyper, and encoding.
rustc-perf results, on a stage 2 build with jemalloc disabled:
Auto merge of #50069 - alexcrichton:fix-proc-macro, r=nrc
proc_macro: Stay on the "use the cache" path more
Discovered in #50061 we're falling off the "happy path" of using a stringified
token stream more often than we should. This was due to the fact that a
user-written token like `0xf` is equality-different from the stringified token
of `15` (despite being semantically equivalent).
This patch updates the call to `eq_unspanned` with an even more awful solution,
`probably_equal_for_proc_macro`, which ignores the value of each token and
basically only compares the structure of the token stream, assuming that the AST
doesn't change just one token at a time.
While this is a step towards fixing #50061 there is still one regression
from #49154 which needs to be fixed.
Auto merge of #50051 - nnethercote:no-env-var, r=Mark-Simulacrum
Lazily evaluate EvalErrorKind::*.into() calls.
eval_context.rs calls `ok_or` in multiple places with an eagerly
evaluated `EvalErrorKind::*.into()` argument, which calls
EvalError::from(), which calls env::var("MIRI_BACKTRACE"), which
allocates a String. This code is hot enough for this to have a
measurable effect on some benchmarks.
This patch changes the `ok_or` calls into `ok_or_else`, thus avoiding
the evaluations when they're not needed. As a result, most of the
rustc-perf benchmarks get a measurable speedup, particularly the
shorter-running ones, where the improvement is as high as 6%.
Output from rustc-perf, comparing stage 2 builds with jemalloc disabled:
Alex Crichton [Thu, 19 Apr 2018 22:52:14 +0000 (15:52 -0700)]
Tweak some stabilizations in libstd
This commit tweaks a few stable APIs in the `beta` branch before they hit
stable. The `str::is_whitespace` and `str::is_alphanumeric` functions were
deleted (added in #49381, issue at #49657). The `and_modify` APIs added
in #44734 were altered to take a `FnOnce` closure rather than a `FnMut` closure.
Auto merge of #48553 - seanmonstar:atomic-debug, r=alexcrichton
atomic: remove 'Atomic*' from Debug output
For the same reason that we don't show `Vec { data: [0, 1, 2, 3] }`, but just the array, the `AtomicUsize(1000)` is noisy, and seeing just `1000` is likely better.
Alex Crichton [Thu, 19 Apr 2018 21:51:59 +0000 (14:51 -0700)]
wasm: Increase default stack size to 1MB
This commit increases the dfeault stack size allocated to the
wasm32-unknown-unknown target to 1MB by default. Currently the default stack
size is one wasm page, or 64 kilobytes. This default stack is quite small and
has caused a stack overflow or two in the wild by accident.
The current "best practice" for fixing this is to pass `-Clink-args='-z
stack-size=$bigger'` but that's not great nor always easy to do. A default of
1MB matches more closely with other platforms where it's "pretty big" by
default.
Note that it was tested and if the users uses `-C link-args` to pass a custom
stack size that's still resepected as lld seems to take the first argument, and
where rustc is passing it will always be last.
Auto merge of #49900 - pnkfelix:compare-mode-nll-followup-3, r=nikomatsakis
Add src/test/ui regression testing for NLL
This PR changes `x.py test` so that when you are running the `ui` test suite, it will also always run `compiletest` in the new `--compare-mode=nll`, which just double-checks that when running under the experimental NLL mode, the output matches the `<source-name>.nll.stderr` file, if present.
In order to reduce the chance of a developer revolt in response to this change, this PR also includes some changes to make the `--compare-mode=nll` more user-friendly:
1. It now generates nll-specific .stamp files, and uses them (so that repeated runs can reuse previously cached results).
2. Each line of terminal output distinguishes whether we are running under `--compare-mode=nll` by printing with the prefix `[ui (nll)]` instead of just the prefix `[ui]`.
Auto merge of #49890 - varkor:xpy-check-rustc_trans, r=alexcrichton
Add rustc_trans to x.py check
r? @Mark-Simulacrum
I looked at `bootstrap/compile.rs` and `bootstrap/check.rs` to try to work out which steps were appropriate, but I'm sure I've overlooked some details here, so it's worth checking carefully I've got all the steps right (e.g. I wasn't sure whether we want to build LLVM if necessary with `x.py check`, though I thought it was probably better to than to not).
From a quick test, it seems to be working, though.
Alex Crichton [Thu, 19 Apr 2018 02:36:48 +0000 (19:36 -0700)]
proc_macro: Stay on the "use the cache" path more
Discovered in #50061 we're falling off the "happy path" of using a stringified
token stream more often than we should. This was due to the fact that a
user-written token like `0xf` is equality-different from the stringified token
of `15` (despite being semantically equivalent).
This patch updates the call to `eq_unspanned` with an even more awful solution,
`probably_equal_for_proc_macro`, which ignores the value of each token and
basically only compares the structure of the token stream, assuming that the AST
doesn't change just one token at a time.
While this is a step towards fixing #50061 there is still one regression
from #49154 which needs to be fixed.
`char_lit` uses an allocation in order to ignore '_' chars in \u{...}
literals. This patch changes it to not do that by processing the chars
more directly.
This improves various rustc-perf benchmark measurements by up to 6%,
particularly regex, futures, clap, coercions, hyper, and encoding.
eval_context.rs calls `ok_or` in multiple places with an eagerly
evaluated `EvalErrorKind::*.into()` argument, which calls
EvalError::from(), which calls env::var("MIRI_BACKTRACE"), which
allocates a String. This code is hot enough for this to have a
measurable effect on some benchmarks.
This patch changes the `ok_or` calls into `ok_or_else`, thus avoiding
the evaluations when they're not needed. As a result, most of the
rustc-perf benchmarks get a measurable speedup, particularly the
shorter-running ones, where the improvement is as high as 6%.
Auto merge of #50022 - nrc:doc-analysis, r=mark-simulacrum
Only emit save-analysis data for `cargo build` tasks
Previously, we were emittinng analysis data for all tasks, including `doc`. That meant we got two sets of save-analysis data, one from the normal build and one from the docs. That means indexing with the RLS took twice as long and made downloads larger and build times longer.
cc https://github.com/rust-lang-nursery/rls/issues/826
Auto merge of #50017 - tinaun:stabilize-all-the-things, r=sfackler
stabilize a bunch of minor api additions
besides `ptr::NonNull::cast` (which is 4 days away from end of FCP) all of these have been finished with FCP for a few weeks now with minimal issues raised
When running under compare-mode=nll, generate expected output to `foo.nll.stderr`
This allows easy revision of the update-references.sh script (included
here) so that it can update the expected output for nll rather than
stderr. It also reminds the rustc developer via the filename that they
are looking at output generated under comapre-mode=nll.
One could argue that there is still a problem with the strategy encoded here:
if we reach a scenario where a change to the compiler brings the output
under AST and NLL modes back into sync, this code will continue to still
generate output to distinct `foo.stderr` and `foo.nll.stderr` files, and
will continue to copy those two files back to corresponding distinct
files in the source tree, even if the *content* of the two files is now the
same.
* Arguably the "right thing" to do in that case is to remove the
`foo.nll.stderr` file entirely.
* However, I think the real answer is that we will probably want to
double-check such cases by hand anyway. We should be regularly
double-checking the diffs between `foo.stderr` and
`foo.nll.stderr`, and if we see a zero-diff case, then we should
evaluate whether that is correct, and if so, remove the file by
hand.)
* In any case, I think the default behavior encoded here (or at
least *intended* to be encoded here) is superior to the
alternative of *only* generating a `foo.nll.stderr` file if one
already existed in the source tree at the time that `compiletest`
was invoked (and otherwise unconditionally generating a
`foo.stderr` file, as was the behavior prior to this commit),
because that alternative is more likely to cause rustc developers
to overwrite a `foo.stderr` file with the stderr output from a
compare-mode=nll run, which will then break the *normal*
`compiletest` run and probably be much more confusing for the
average rustc developer.
Workaround rust-lang/rust#49998 by opting into experimental `-Z nll-subminimal-causes` flag
This commit only applies the flag to the one test case,
ui/span/dropck_vec_cycle_checked.rs, that absolutely needs it. Without
the flag, that test takes an unknown amount of time (greater than 1
minute) to compile. But its possible that other tests would also
benefit from the flag, and we may want to make it the default (after
evaluating its impact on other tests).
In terms of its known impact on other tests, I have only evaluated the
ui tests, and the *only* ui test I have found that the flag impacts
(running under NLL mode, of course), is src/test/ui/nll/issue-31567.rs
In particular:
```
% ./build/x86_64-unknown-linux-gnu/stage1/bin/rustc ../src/test/ui/nll/issue-31567.rs
error[E0597]: `*v.0` does not live long enough
--> ../src/test/ui/nll/issue-31567.rs:22:26
|
22 | let s_inner: &'a S = &*v.0; //~ ERROR `*v.0` does not live long enough
| ^^^^^ borrowed value does not live long enough
23 | &s_inner.0
24 | }
| - borrowed value only lives until here
|
note: borrowed value must be valid for the lifetime 'a as defined on the function body at 21:1...
--> ../src/test/ui/nll/issue-31567.rs:21:1
|
21 | fn get_dangling<'a>(v: VecWrapper<'a>) -> &'a u32 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to previous error
For more information about this error, try `rustc --explain E0597`.
% ./build/x86_64-unknown-linux-gnu/stage1/bin/rustc ../src/test/ui/nll/issue-31567.rs -Z nll-subminimal-causes
error[E0597]: `*v.0` does not live long enough
--> ../src/test/ui/nll/issue-31567.rs:22:26
|
22 | let s_inner: &'a S = &*v.0; //~ ERROR `*v.0` does not live long enough
| ^^^^^ borrowed value does not live long enough
23 | &s_inner.0
24 | }
| -
| |
| borrowed value only lives until here
| borrow later used here, when `v` is dropped
error: aborting due to previous error
For more information about this error, try `rustc --explain E0597`.
%
```
projects / rust.git / log