Corey Farwell [Tue, 28 Feb 2017 13:33:10 +0000 (08:33 -0500)]
Rollup merge of #40131 - MajorBreakfast:patch-3, r=steveklabnik
Make lifetime elision docs clearer
Previously it said
"It's forbidden to allow reasoning about types based on the item signature alone."
I think that sentence is wrong. Rust **uses** the item signatures to perform type inference within the body. I think what's meant is the other way around: It does not infer types for item signatures.
Corey Farwell [Tue, 28 Feb 2017 13:33:07 +0000 (08:33 -0500)]
Rollup merge of #40122 - robinst:process-add-example-for-writing-to-stdin, r=alexcrichton
Example for how to provide stdin using std::process::Command
Spawning a child process and writing to its stdin is a bit tricky due to
`as_mut` and having to use a limited borrow. An example for this might
help newer users.
Corey Farwell [Tue, 28 Feb 2017 13:33:04 +0000 (08:33 -0500)]
Rollup merge of #40056 - keeperofdakeys:contributing, r=alexcrichton
Replace ./configure with config.toml in README.md and CONTRIBUTING.md
Replace ./configure with config.toml in README.md and CONTRIBUTING.md, so that new users aren't confused about which build system to use, and how to configure the build process.
Corey Farwell [Tue, 28 Feb 2017 13:33:00 +0000 (08:33 -0500)]
Rollup merge of #39977 - frewsxcv:error-reporting-cleanup, r=eddyb
librustc error_reporting.rs cleanup.
Read some code in librustc, mainly in error_reporting.rs, and cleaned up some things along the way. I recommend looking at each commit individually or looking at the [whitespace insensitive diff](https://github.com/rust-lang/rust/pull/39977/files?w=1).
bors [Tue, 28 Feb 2017 10:00:31 +0000 (10:00 +0000)]
Auto merge of #40135 - alexcrichton:split-android, r=aturon
travis: Split Android into dist/test images
PRs can't land againt beta right now because the android bot is filling up on
disk space. I don't really know what's going on but the android bot is the
longest one to run anyway so it'll benefit from being split up regardless.
bors [Tue, 28 Feb 2017 07:59:25 +0000 (07:59 +0000)]
Auto merge of #40008 - eddyb:lazy-12, r=nikomatsakis
[12/12] On-demand type-checking, const-evaluation, MIR building & const-qualification.
_This is the last of a series ([prev](https://github.com/rust-lang/rust/pull/38813)) of patches designed to rework rustc into an out-of-order on-demand pipeline model for both better feature support (e.g. [MIR-based](https://github.com/solson/miri) early constant evaluation) and incremental execution of compiler passes (e.g. type-checking), with beneficial consequences to IDE support as well.
If any motivation is unclear, please ask for additional PR description clarifications or code comments._
<hr>
As this contains all of the changes that didn't fit neatly into other PRs, I'll be elaborating a bit:
### User-facing changes
* when determining whether an `impl Trait` type implements an auto-trait (e.g. `Send` or `Sync`), the function the `impl Trait` came from has to be inferred and type-checking, disallowing cycles
* this results from not having an obvious place to put the "deferred obligation" in on-demand atm
* while we could model side-effects like that and "post-processing passes" better, it's still more limiting than being able to know the result in the original function (e.g. specialization) *and* there are serious problems around region-checking (if a `Send` impl required `'static`, it wasn't enforced)
* early const-eval requires type-checking and const-qualification to be performed first, which means:
* you get the intended errors before (if any) constant evaluation error that is simply fallout
* associated consts should always work now, and `const fn` type parameters are properly tracked
* don't get too excited, array lengths still can't depend on type parameters
* #38864 works as intended now, with `Self` being allowed in `impl` bounds
* #32205 is largely improved, with associated types being limited to "exact match" `impl`s (as opposed to traversing the specialization graph to resolve unspecified type parameters to their defaults in another `impl` or in the `trait`) *while* checking for overlaps building the specialization graph for that trait - once all the trait impls' have been checked for coherence (including ahead-of-time/on-demand), it's uniform
* [crater report](https://gist.github.com/eddyb/bbb869072468c7e08d6d808e75938051) looks clean (aside from `clippy` which broke due to `rustc` internal changes)
### Compiler-internal changes
* `ty::Generics`
* no longer contains the actual type parameter defaults, instead they're associated with the type parameter's `DefId`, like associated types in a trait definition
* this allows computing `ty::Generics` as a leaf (reading only its own HIR)
* holds a mapping from `DefIndex` of type parameters to their indices
* `ty::AdtDef`
* only tracks `#[repr(simd)]` in its `ReprOptions` `repr` field
* doesn't contain `enum` discriminant values, but instead each variant either refers to either an explicit value for its discriminant, or the distance from the last explicit discriminant, if any
* the `.discriminants(tcx)` method produces an iterator of `ConstInt` values, looking up explicit discriminants in a separate map, if necessary
* this allows computing `ty::AdtDef` as a leaf (reading only its own HIR)
* Small note: the two above (`Generics`, `AdtDef`), `TraitDef` and `AssociatedItem` should probably end up as part of the HIR, eventually, as they're trivially constructed from it
* `ty::FnSig`
* now also holds ABI and unsafety, alongside argument types, return type and C variadicity
* `&ty::BareFnTy` and `ty::ClosureTy` have been replaced with `PolyFnSig = Binder<FnSig>`
* `BareFnTy` was interned and `ClosureTy` was treated as non-trivial to `Clone` because they had a `PolyFnSig` and so used to contain a `Vec<Ty>` (now `&[Ty]`)
* `ty::maps`
* all the `DepTrackingMap`s have been grouped in a structure available at `tcx.maps`
* when creating the `tcx`, a set of `Providers` (one `fn` pointer per map) is required for the local crate, and one for all other crates (i.e. metadata loading), `librustc_driver` plugging the various crates (e.g. `librustc_metadata`, `librustc_typeck`, `librustc_mir`) into it
* when a map is queried and the value is missing, the appropriate `fn` pointer from the `Providers` of that crate is called with the `TyCtxt` and the key being queried, to produce the value on-demand
* `rustc_const_eval`
* demands both `typeck_tables` and `mir_const_qualif` (in preparation for miri)
* tracks `Substs` in `ConstVal::Function` for `const fn` calls
* returns `TypeckError` if type-checking has failed (or cases that can only be reached if it had)
* this error kind is never reported, resulting in less noisy/redundant diagnostics
* fixes #39548 (testcase by @larsluthman, taken from #39812, which this supersedes)
* on-demand has so far been hooked up to:
* `rustc_metadata::cstore_impl`: `ty`, `generics`, `predicates`, `super_predicates`, `trait_def`, `adt_def`, `variances`, `associated_item_def_ids`, `associated_item`, `impl_trait_ref`, `custom_coerce_unsized_kind`, `mir`, `mir_const_qualif`, `typeck_tables`, `closure_kind`, `closure_type`
* `rustc_typeck::collect`: `ty`, `generics`, `predicates`, `super_predicates`, `type_param_predicates`, `trait_def`, `adt_def`, `impl_trait_ref`
* `rustc_typeck::coherence`: `coherent_trait`, `coherent_inherent_impls`
* `rustc_typeck::check`: `typeck_tables`, `closure_type`, `closure_kind`
* `rustc_mir::mir_map`: `mir`
* `rustc_mir::transform::qualify_consts`: `mir_const_qualif`
Alex Crichton [Mon, 27 Feb 2017 22:53:12 +0000 (14:53 -0800)]
travis: Split Android into dist/test images
PRs can't land againt beta right now because the android bot is filling up on
disk space. I don't really know what's going on but the android bot is the
longest one to run anyway so it'll benefit from being split up regardless.
bors [Tue, 28 Feb 2017 02:26:09 +0000 (02:26 +0000)]
Auto merge of #40095 - alexcrichton:sccache-mingw, r=brson
appveyor: Use sccache on pc-windows-gnu for caching
Now that mozilla/sccache#43 is fixed the caching works for MinGW on Windows. We
still can't use it for MSVC just yet, but I'll try to revive that branch at some
point.
Alex Crichton [Sat, 25 Feb 2017 08:53:12 +0000 (00:53 -0800)]
appveyor: Use sccache on pc-windows-gnu for caching
Now that mozilla/sccache#43 is fixed the caching works for MinGW on Windows. We
still can't use it for MSVC just yet, but I'll try to revive that branch at some
point.
bors [Mon, 27 Feb 2017 17:21:37 +0000 (17:21 +0000)]
Auto merge of #38165 - Yamakaky:better-backtrace, r=petrochenkov
Improve backtrace formating while panicking.
Fixes #37783.
Done:
- Fix alignment of file paths for better readability
- `RUST_BACKTRACE=full` prints all the informations (current behaviour)
- `RUST_BACKTRACE=(short|yes)` is the default and does:
- Skip irrelevant frames at the beginning and the end
- Remove function address
- Remove the current directory from the absolute paths
- Remove `::hfabe6541873` at the end of the symbols
- `RUST_BACKTRACE=(0|no)` disables the backtrace.
- `RUST_BACKTRACE=<everything else>` is equivalent to `short` for
backward compatibility.
- doc
- More uniform printing across platforms.
Removed, TODO in a new PR:
- Remove path prefix for libraries and libstd
Example of short backtrace:
```rust
fn fail() {
panic!();
}
fn main() {
let closure = || fail();
closure();
}
```
Short:
```
thread 'main' panicked at 'explicit panic', t.rs:2
Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
0: t::fail
at ./t.rs:2
1: t::main::{{closure}}
at ./t.rs:6
2: t::main
at ./t.rs:7
```
Full:
```
thread 'main' panicked at 'This function never returns!', t.rs:2
stack backtrace:
0: 0x558ddf666478 - std::sys::imp::backtrace::tracing::imp::unwind_backtrace::hec84c9dd8389cc5d
at /home/yamakaky/dev/rust/rust/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
1: 0x558ddf65d90e - std::sys_common::backtrace::_print::hfa25f8b31f4b4353
at /home/yamakaky/dev/rust/rust/src/libstd/sys_common/backtrace.rs:71
2: 0x558ddf65cb5e - std::sys_common::backtrace::print::h9b711e11ac3ba805
at /home/yamakaky/dev/rust/rust/src/libstd/sys_common/backtrace.rs:60
3: 0x558ddf66796e - std::panicking::default_hook::{{closure}}::h736d216e74748044
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:355
4: 0x558ddf66743c - std::panicking::default_hook::h16baff397e46ea10
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:371
5: 0x558ddf6682bc - std::panicking::rust_panic_with_hook::h6d5a9bb4eca42c80
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:559
6: 0x558ddf64ea93 - std::panicking::begin_panic::h17dc549df2f10b99
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:521
7: 0x558ddf64ec42 - t::diverges::he6bc43fc925905f5
at /tmp/p/t.rs:2
8: 0x558ddf64ec5a - t::main::h0ffc20356b8a69c0
at /tmp/p/t.rs:6
9: 0x558ddf6687f5 - core::ops::FnOnce::call_once::hce41f19c0db56f93
10: 0x558ddf667cde - std::panicking::try::do_call::hd4c8c97efb4291df
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:464
11: 0x558ddf698d77 - __rust_try
12: 0x558ddf698c57 - __rust_maybe_catch_panic
at /home/yamakaky/dev/rust/rust/src/libpanic_unwind/lib.rs:98
13: 0x558ddf667adb - std::panicking::try::h2c56ed2a59ec1d12
at /home/yamakaky/dev/rust/rust/src/libstd/panicking.rs:440
14: 0x558ddf66cc9a - std::panic::catch_unwind::h390834e0251cc9af
at /home/yamakaky/dev/rust/rust/src/libstd/panic.rs:361
15: 0x558ddf6809ee - std::rt::lang_start::hb73087428e233982
at /home/yamakaky/dev/rust/rust/src/libstd/rt.rs:57
16: 0x558ddf64ec92 - main
17: 0x7fecb869e290 - __libc_start_main
18: 0x558ddf64e8b9 - _start
19: 0x0 - <unknown>
```
Robin Stocker [Mon, 27 Feb 2017 06:01:47 +0000 (17:01 +1100)]
Example for how to provide stdin using std::process::Command
Spawning a child process and writing to its stdin is a bit tricky due to
`as_mut` and having to use a limited borrow. An example for this might
help newer users.
bors [Sun, 26 Feb 2017 15:15:23 +0000 (15:15 +0000)]
Auto merge of #40112 - alexcrichton:fetch-all, r=brson
travis: Make more network requests retryable
This commit attempts to move more network operations to being retryable through
various operations. For example git submodule updates, downloading snapshots,
etc, are now all in retryable steps.
Hopefully this commit can cut down on the number of network failures we've been
seeing!
Alex Crichton [Sat, 25 Feb 2017 08:00:47 +0000 (00:00 -0800)]
travis: Make more network requests retryable
This commit attempts to move more network operations to being retryable through
various operations. For example git submodule updates, downloading snapshots,
etc, are now all in retryable steps.
Hopefully this commit can cut down on the number of network failures we've been
seeing!
Rollup merge of #40037 - froydnj:overflow-checks, r=alexcrichton
add `-C overflow-checks` option
In addition to defining and handling the new option, we also add a method on librustc::Session for determining the necessity of overflow checks. This method provides a single point to sort out the three (!) different ways for turning on overflow checks: -C debug-assertions, -C overflow-checks, and -Z force-overflow-checks.
I was seeing a [run-pass/issue-28950.rs](https://github.com/rust-lang/rust/blob/b1363a73ede57ae595f3a1be2bb75d308ba4f7f6/src/test/run-pass/issue-28950.rs) failure on my machine with these patches, but I was also seeing the failure without the changes to the core compiler. We'll see what travis says.
Rollup merge of #40024 - raphlinus:readdir, r=alexcrichton
Switch Fuchsia to readdir (instead of readdir_r)
The readdir_r function is deprecated on newer Posix systems because of
various problems, and not implemented at all for Fuchsia. There are
already implementations using both, and this patch switches Fuchsia
over to the readdir-based one.
Fixes #40021 for Fuchsia, but that issue also contains discussion of
what should happen for other Posix systems.
Rollup merge of #40019 - alexcrichton:fix-musl, r=brson
travis: Compile a more compatible libc.a for musl
The mitigations for #34978 involve passing `-Wa,-mrelax-relocations=no` to all C
code we compile, and we just forgot to pass it when compiling musl itself.
Rollup merge of #39995 - Aatch:vtable-ptr-metadata, r=arielb1
Set metadata for vtable-related loads
Give LLVM much more information about vtable pointers. Without the extra
information, LLVM has to be rather pessimistic about vtables, preventing
a number of obvious optimisations.
* Makes the vtable pointer argument noalias and readonly.
* Marks loads of the vtable pointer as nonnull.
* Marks load from the vtable with `!invariant.load` metadata.
Rollup merge of #39988 - arthurprs:hm-adapt2, r=alexcrichton
Simplify/fix adaptive hashmap
Please see https://github.com/rust-lang/rust/pull/38368#issuecomment-280957863 for context.
The shift length math is broken. It turns out that checking for the shift length is complicated. Using simulations it's possible to see that a value of 2000 will only get probabilities down to ~1e-7 when the hashmap load factor is 90% (rust goes up to 90.9% as of today). That's probably not good enough to go into the stdlib with pluggable hashers.
So this PR simplify the adaptive behavior to only consider displacement, which is much safer and very useful by itself.
There's two comments because one of them is already being tested to be merged by bors.
Rollup merge of #39945 - petrochenkov:llvmtarg, r=alexcrichton
Use ARM instead of SystemZ for testing uninstalled targets
This needs some explanation.
`config.toml` has section `targets` listing backends that are built during LLVM build:
```
targets = "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX"
```
It would be reasonable to expect that `targets = "X86"` would be enough for doing a local build in typical case (building on x86 and not working on some non-x86 platform-specific functionality).
However, for `x.py test` to pass successfully you have to add ARM and SystemZ to the target list as well (`targets = "X86;ARM;SystemZ"`), because two tests (`compile-fail/issue-37131.rs` and `run-make\target-without-atomics`) require these architectures to be enabled in LLVM.
This patch moves `compile-fail/issue-37131.rs` from SystemZ to ARM, so `targets = "X86;ARM"` becomes sufficient for running the full test suite without errors.
Rollup merge of #39914 - raphlinus:mx_handle_wait, r=alexcrichton
Follow rename of mx_handle_wait Magenta syscalls
The mx_handle_wait_* syscalls in Magenta were renamed to
mx_object_wait. The syscall is used in the Magenta/Fuchsia
implementation of std::process, to wait on child processes.
In addition, this patch enables the use of the system provided
libbacktrace library on Fuchsia targets. Symbolization is not yet
working, but at least it allows printing hex addresses in a backtrace
and makes building succeed when the backtrace feature is not disabled.
Rollup merge of #39888 - nagisa:on-fail-bootstrap, r=alexcrichton
[rustbuild] add a way to run command after failure
This is a simple way to workaround the debugging issues caused by the rustc
wrapper used in the bootstrap process. Namely, it uses some obscure environment
variables and you can't just copy the failed command and run it in the shell or
debugger to examine the failure more closely.
With `--on-fail` its possible to run an arbitrary command within exactly the
same environment under which rustc failed. Theres's multiple ways to use this
new flag:
$ python x.py build --stage=1 --on-fail=env
would print a list of environment variables and the failed command, so a
few copy-pastes and you now can run the same rust in your shell outside the
bootstrap system.
$ python x.py build --stage=1 --on-fail=bash
Is a more useful variation of the command above in that it launches a whole
shell with environment already in place! All that's left to do is copy-paste
the command just above the shell prompt!
bors [Sat, 25 Feb 2017 03:10:23 +0000 (03:10 +0000)]
Auto merge of #40084 - alexcrichton:update-sccache, r=aturon
Update sccache binaries on CI
Currently CI builds can fail spuriously during the LLVM build (#39003). I
believe this is due to sccache, and I believe that in turn was due to the fact
that the sccache server used to just be a raw mio server. Historically raw mio
servers are quite complicated to get right, but this is why we built Tokio! The
sccache server has been migrated to Tokio which I suspect would fix any latent
issues.
I have no confirmation of this (never been able to reproduce the deadlock
locally), but my hunch is that updating sccache to the master branch will fix
the timeouts during the LLVM build.
The binaries previously came from Gecko's infrastructure, but I've built new
ones by hand for Win/Mac/Linux and uploaded them to our CI bucket.
Alex Crichton [Fri, 24 Feb 2017 21:16:54 +0000 (13:16 -0800)]
Update sccache binaries on CI
Currently CI builds can fail spuriously during the LLVM build (#39003). I
believe this is due to sccache, and I believe that in turn was due to the fact
that the sccache server used to just be a raw mio server. Historically raw mio
servers are quite complicated to get right, but this is why we built Tokio! The
sccache server has been migrated to Tokio which I suspect would fix any latent
issues.
I have no confirmation of this (never been able to reproduce the deadlock
locally), but my hunch is that updating sccache to the master branch will fix
the timeouts during the LLVM build.
The binaries previously came from Gecko's infrastructure, but I've built new
ones by hand for Win/Mac/Linux and uploaded them to our CI bucket.
Previously the sysroot directory was purged on every build and mingw startup objects were rebuilt unconditionally and always triggered test reruns.
Now mingw startup objects are built in the native directory and then copied into the sysroot directory. They are also rebuilt only when necessary, so test caching works.