Guillaume Gomez [Tue, 30 Aug 2016 08:39:05 +0000 (10:39 +0200)]
Rollup merge of #35810 - matthew-piziak:fn-trait-example, r=steveklabnik
improve documentation for `Fn*` traits
This PR is not yet a serious attempt at contribution. Rather, I'm opening this for discussion. I can think of a few things we may want to accomplish with the documentation of the `Fn`, `FnMut`, and `FnOnce` traits:
- the relationship between these traits and the closures that implement them
- examples of non-closure implementations
- the relationship between these traits and Rust's ownership semantics
Fixes #36023 by backporting @majnemer's LLVM patch fixing [the LLVM bug](https://llvm.org/bugs/show_bug.cgi?id=29163.) where SimplifyCFG hoisted instructions andkept their metadata (conditional `!nonnull` loads could kill a null check later if hoisted).
bors [Mon, 29 Aug 2016 04:57:51 +0000 (21:57 -0700)]
Auto merge of #36062 - japaric:smarter-submodules, r=alexcrichton
rustbuild: smarter `git submodule`-ing
With this commit, if one bootstraps rust against system llvm then the
src/llvm submodule is not updated/checked-out. This saves considerable
network bandwith when starting from a fresh clone of rust-lang/rust as
the llvm submodule is never cloned.
cc #30107
r? @alexcrichton
cc @petevine
~~We could also avoid updating the jemalloc submodule if --disable-jemalloc is used. It just hasn't been implemented.~~ Done
This probably doesn't handle "recursive" submodules correctly but I think we don't have any of those right now.
I'm still testing a bootstrap but already confirmed that the llvm submodule doesn't get updated when `--llvm-root` is passed to `configure`.
bors [Sun, 28 Aug 2016 17:19:52 +0000 (10:19 -0700)]
Auto merge of #35984 - jonas-schievink:reproducible-builds, r=eddyb
Steps towards reproducible builds
cc #34902
Running `make dist` twice will result in a rustc tarball where only `librustc_back.so`, `librustc_llvm.so` and `librustc_trans.so` differ. Building `libstd` and `libcore` twice with the same compiler and flags produces identical artifacts.
bors [Sun, 28 Aug 2016 07:36:16 +0000 (00:36 -0700)]
Auto merge of #36028 - japaric:s390x, r=alexcrichton
initial support for s390x
A new target, `s390x-unknown-linux-gnu`, has been added to the compiler
and can be used to build no_core/no_std Rust programs.
Known limitations:
- librustc_trans/cabi_s390x.rs is missing. This means no support for
`extern "C" fn`.
- No support for this arch in libc. This means std can't be cross
compiled for this target.
r? @alexcrichton
This time I couldn't test running a binary cross compiled to this target under QEMU because the qemu-s390x that ships with Ubuntu 16.04 SIGABRTs with every s390x binary I run it with.
Change in binary size of `librustc_llvm.so`:
Without this commit (stage1): 41895736 bytes
With this commit (stage1): 42899016 bytes
bors [Sun, 28 Aug 2016 04:20:28 +0000 (21:20 -0700)]
Auto merge of #36027 - eddyb:unsized-prefix, r=nagisa
rustc_trans: don't round up the DST prefix size to its alignment.
Fixes #35815 by using `ty::layout` and `min_size` to compute the size of the DST prefix.
`ty::layout::Struct::min_size` is not rounded up to alignment, which could be smaller for the DST field.
Jorge Aparicio [Sun, 28 Aug 2016 02:33:38 +0000 (21:33 -0500)]
rustbuild: smarter `git submodule`-ing
With this commit, if one bootstraps rust against system llvm then the
src/llvm submodule is not updated/checked-out. This saves considerable
network bandwith when starting from a fresh clone of rust-lang/rust as
the llvm submodule is never cloned.
bors [Sat, 27 Aug 2016 14:52:20 +0000 (07:52 -0700)]
Auto merge of #35969 - bluss:memrchr-alignment, r=nagisa
memrchr: Correct aligned offset computation
The memrchr fallback did not compute the offset correctly. It was
intentioned to land on usize-aligned addresses but did not.
This was suspected to have resulted in a crash on ARMv7!
This bug affected non-linux platforms.
I think like this, if we have a slice with pointer `ptr` and length
`len`, we want to find the last usize-aligned offset in the slice.
The correct computation should be:
For example if ptr = 1 and len = 6, and `size_of::<usize>()` is 4:
```
[ x x x x x x ]
1 2 3 4 5 6
^-- last aligned address at offset 3 from the start.
```
The last aligned address is ptr + len - (ptr + len) % usize_size.
Jonas Schievink [Tue, 23 Aug 2016 20:02:47 +0000 (22:02 +0200)]
Make metadata encoding deterministic
`ty::Predicate` was being used as a key for a hash map, but its hash
implementation indirectly hashed addresses, which vary between each
compiler run. This is fixed by sorting predicates by their ID before
encoding them.
In my tests, rustc is now able to produce deterministic results when
compiling libcore and libstd.
I've beefed up `run-make/reproducible-build` to compare the produced
artifacts bit-by-bit. This doesn't catch everything, but should be a
good start.
Jonas Schievink [Mon, 22 Aug 2016 22:57:54 +0000 (00:57 +0200)]
Use `FnvHashMap` in more places
* A step towards #34902
* More stable error messages in some places related to crate loading
* Possible slight performance improvements since all `HashMap`s
replaced had small keys where `FnvHashMap` should be faster
(although I didn't measure)
One of `self.list`s has type
```
&ReFree(CodeExtent(15013/CallSiteScope { fn_id: 18907, body_id: 18912 }), BrNamed(0:DefIndex(3066), 'a(397), WontChange)) mut linked_list::LinkedList<T>
```
and other has type
```
&ReScope(CodeExtent(15018/Remainder(BlockRemainder { block: 18912, first_statement_index: 0 }))) mut linked_list::LinkedList<T>
```
(... but I'm not sure it's not a bug actually.)
2) Not hashing types is faster than hashing types.
Rollup merge of #36002 - eddyb:abstract-kindness, r=nikomatsakis
Combine types and regions in Substs into one interleaved list.
Previously, `Substs` would contain types and regions, in two separate vectors, for example:
```rust
<X as Trait<'a, 'b, A, B>>::method::<'p, 'q, T, U>
/* corresponds to */
Substs { regions: ['a, 'b, 'p, 'q], types: [X, A, B, T, U] }
```
This PR continues the work started in #35605 by further removing the distinction.
A new abstraction over types and regions is introduced in the compiler, `Kind`.
Each `Kind` is a pointer (`&TyS` or `&Region`), with the lowest two bits used as a tag.
Two bits were used instead of just one (type = `0`, region = `1`) to allow adding more kinds.
`Substs` contain only a `Vec<Kind>`, with `Self` first, followed by regions and types (in the definition order):
```rust
Substs { params: [X, 'a, 'b, A, B, 'p, 'q, T, U] }
```
The resulting interleaved list has the property of being the concatenation of parameters for the (potentially) nested generic items it describes, and can be sliced back into those components:
```rust
params[0..5] = [X, 'a, 'b, A, B] // <X as Trait<'a, 'b, A, B>>
params[5..9] = ['p, 'q, T, U] // <_>::method::<'p, 'q, T, U>
```
Rollup merge of #35953 - Aatch:better-missing-block-error, r=nrc
Improve error message when failing to parse a block
We want to catch this error:
```
if (foo)
bar;
```
as it's valid syntax in other languages, and say how to fix it.
Unfortunately it didn't care if the suggestion made sense and just
highlighted the unexpected token.
Now it attempts to parse a statement, and if it succeeds, it shows the
help message.
Rollup merge of #35124 - steveklabnik:remove_style, r=aturon
Remove style guide.
We originally imported this into the repository with the intent of
fixing it up. Instead, nothing happened.
Its appearance on rust-lang.org makes it seem semi-official, but it's
not. The rustfmt strike team will end up producing something like this
anyway, and leaving it around does nothing but mislead people.
Jorge Aparicio [Sat, 27 Aug 2016 02:05:16 +0000 (21:05 -0500)]
initial support for s390x
A new target, `s390x-unknown-linux-gnu`, has been added to the compiler
and can be used to build no_core/no_std Rust programs.
Known limitations:
- librustc_trans/cabi_s390x.rs is missing. This means no support for
`extern "C" fn`.
- No support for this arch in libc. This means std can be cross compiled
for this target.
bors [Fri, 26 Aug 2016 10:29:45 +0000 (03:29 -0700)]
Auto merge of #35975 - jonathandturner:error_buffering, r=alexcrichton
Buffer unix and lock windows to prevent message interleaving
When cargo does a build on multiple processes, multiple crates may error at the same time. If this happens, currently you'll see interleaving of the error messages, which makes for an unreadable message.
| | ^^^^^^^^^^ expected struct `std::io::Error`, found () expected struct `std::io::Error`, found ()
||
= = notenote: expected type `std::io::Error`: expected type `std::io::Error`
= = notenote: found type `()`: found type `()`
= = notenote: required because of the requirements on the impl of `futures_minihttp::Service<futures_minihttp::Request, futures_minihttp::Response>` for `[closure@src/bin/multithread-unix.rs:16:41: 22:6]`: required because of the requirements on the impl of `futures_minihttp::Service<futures_minihttp::Request, futures_minihttp::Response>` for `[closure@src/bin/singlethread.rs:16:30: 22:6]`
error: aborting due to previous error
error: aborting due to previous error
```
This patch uses two techniques to prevent this interleaving. On Unix systems, since they use the text-based ANSI protocol for coloring, we can safely buffer up whole messages before we emit. This PR does this buffering, and emits the whole message at once.
On Windows, term must use the Windows terminal API to color the output. This disallows us from using the same buffering technique. Instead, here we grab a Windows mutex (thanks to @alexcrichton for the lock code). This lock only works in Windows and will hold a mutex for the duration of a message output.
Steve Klabnik [Fri, 29 Jul 2016 22:56:09 +0000 (18:56 -0400)]
Remove style guide.
We originally imported this into the repository with the intent of
fixing it up. Instead, nothing happened.
Its appearance on rust-lang.org makes it seem semi-official, but it's
not. The rustfmt strike team will end up producing something like this
anyway, and leaving it around does nothing but mislead people.
bors [Thu, 25 Aug 2016 18:28:30 +0000 (11:28 -0700)]
Auto merge of #34923 - eddyb:deny-fn-item-transmute, r=nikomatsakis
Deny (by default) transmuting from fn item types to pointer-sized types.
This sets the #19925 lint (transmute from zero-sized fn item type) to `deny` by default.
Technically a `[breaking-change]`, but will not affect dependent crates because of `--cap-lints`.
bors [Thu, 25 Aug 2016 15:32:19 +0000 (08:32 -0700)]
Auto merge of #35884 - habnabit:freebsd-arc4rand, r=alexcrichton
Use arc4rand(9) on FreeBSD
From rust-lang-nursery/rand#112:
>After reading through #30691 it seems that there's general agreement that using OS-provided facilities for seeding rust userland processes is fine as long as it doesn't use too much from libc. FreeBSD's `arc4random_buf(3)` is not only a whole lot of libc code, but also not even currently exposed in the libc crate. Fortunately, the mechanism `arc4random_buf(3)` et al. use for getting entropy from the kernel ([`arc4rand(9)`](https://www.freebsd.org/cgi/man.cgi?query=arc4random&apropos=0&sektion=9&manpath=FreeBSD+10.3-RELEASE&arch=default&format=html)) is exposed via `sysctl(3)` with constants that are already in the libc crate.
>I haven't found too much documentation on `KERN_ARND`—it's missing or only briefly described in most of the places that cover sysctl mibs. But, from digging through the kernel source, it appears that the sysctl used in this PR is very close to just calling `arc4rand(9)` directly (with `reseed` set to 0 and no way to change it).
I expected [rand](/rust-lang-nursery/rand) to reply quicker, so I tried submitting it there first. It's been a few weeks with no comment, so I don't know the state of it, but maybe someone will see it here and have an opinion. This is basically the same patch. It pains me to duplicate the code but I guess it hasn't been factored out into just one place yet.
Rollup merge of #35916 - eddyb:mir-no-dead-allocas, r=Aatch
rustc_trans: do not generate allocas for unused locals.
This fixes a regression observed in a [`mio` test](https://travis-ci.org/carllerche/mio/jobs/152142886) which was referencing a 4MB `const` array.
Even though MIR rvalue promotion would promote the borrow of the array, a dead temp was left behind.
As the array doesn't have an immediate type, an `alloca` was generated for it, even though it had no uses.
The fix is pretty dumb: assume that locals need to be borrowed or assigned before being used.
And if it can't be used, it doesn't get an `alloca`, even if the type would otherwise demand it.
This could change in the future, but all the MIR we generate now doesn't break that rule.
Rollup merge of #35238 - vadimcn:macro-debug-locs, r=michaelwoerister
Fix debug line number info for macro expansions.
Macro expansions result in code tagged with completely different debug locations than the surrounding expressions. This wrecks havoc on debugger's ability the step over source lines.
This change fixes the problem by tagging expanded code as "inlined" at the macro expansion site, which allows the debugger to sort it out.
Note that only the outermost expansion is currently handled, stepping into a macro will still result in stepping craziness.
Vadim Chugunov [Thu, 25 Aug 2016 02:34:31 +0000 (19:34 -0700)]
Fix debug line info for macro expansions.
Macro expansions produce code tagged with debug locations that are completely different from the surrounding expressions. This wrecks havoc on debugger's ability the step over source lines.
In order to have a good line stepping behavior in debugger, we overwrite debug locations of macro expansions with that of the outermost expansion site.
bors [Thu, 25 Aug 2016 06:05:47 +0000 (23:05 -0700)]
Auto merge of #35814 - alexcrichton:armv7-no-neon, r=brson
rustc: Don't enable NEON by default on armv7 Linux
One of the primary platforms for the `armv7-unknown-linux-gnueabihf` target,
Linux distributions, do not enable NEON extensions by default. This PR disables
that feature by defualt but enables the `d16` feature which enables VFP3D16 that
distributions do enable.
bors [Wed, 24 Aug 2016 21:57:34 +0000 (14:57 -0700)]
Auto merge of #35764 - eddyb:byegone, r=nikomatsakis
Remove the old AST-based backend from rustc_trans.
Starting with Rust 1.13, `--disable-orbit` , `-Z orbit=off` and `#[rustc_no_mir]` have been removed.
Only the new MIR backend is left in the compiler, and only early const_eval uses ASTs from other crates.
Filling drop (previously "zeroing drop"), `#[unsafe_no_drop_flag]` and associated unstable APIs are gone.
Implementing `Drop` doesn't add a flag anymore to the type, all of the dynamic drop is function local.
This is a [breaking-change], please use `Option::None` and/or `mem::forget` if you are unsure about your ability to prevent/control the drop of a value. In the future, `union` will be usable in some such cases.
**NOTE**: DO NOT MERGE before we get the new beta as the stage0, there's some cruft to remove.
All of this will massively simplify any efforts to implement (and as such it blocks) features such as `union`s, safe use of `#[packed]` or new type layout optimizations, not to mention many other experiments.