bors [Sat, 30 Jan 2016 00:25:44 +0000 (00:25 +0000)]
Auto merge of #30448 - alexcrichton:llvmup, r=nikomatsakis
These commits perform a few high-level changes with the goal of enabling i686 MSVC unwinding:
* LLVM is upgraded to pick up the new exception handling instructions and intrinsics for MSVC. This puts us somewhere along the 3.8 branch, but we should still be compatible with LLVM 3.7 for non-MSVC targets.
* All unwinding for MSVC targets (both 32 and 64-bit) are implemented in terms of this new LLVM support. I would like to also extend this to Windows GNU targets to drop the runtime dependencies we have on MinGW, but I'd like to land this first.
* Some tests were fixed up for i686 MSVC here and there where necessary. The full test suite should be passing now for that target.
In terms of landing this I plan to have this go through first, then verify that i686 MSVC works, then I'll enable `make check` on the bots for that target instead of just `make` as-is today.
Alex Crichton [Sat, 24 Oct 2015 01:18:44 +0000 (18:18 -0700)]
trans: Reimplement unwinding on MSVC
This commit transitions the compiler to using the new exception handling
instructions in LLVM for implementing unwinding for MSVC. This affects both 32
and 64-bit MSVC as they're both now using SEH-based strategies. In terms of
standard library support, lots more details about how SEH unwinding is
implemented can be found in the commits.
In terms of trans, this change necessitated a few modifications:
* Branches were added to detect when the old landingpad instruction is used or
the new cleanuppad instruction is used to `trans::cleanup`.
* The return value from `cleanuppad` is not stored in an `alloca` (because it
cannot be).
* Each block in trans now has an `Option<LandingPad>` instead of `is_lpad: bool`
for indicating whether it's in a landing pad or not. The new exception
handling intrinsics require that on MSVC each `call` inside of a landing pad
is annotated with which landing pad that it's in. This change to the basic
block means that whenever a `call` or `invoke` instruction is generated we
know whether to annotate it as part of a cleanuppad or not.
* Lots of modifications were made to the instruction builders to construct the
new instructions as well as pass the tagging information for the call/invoke
instructions.
* The translation of the `try` intrinsics for MSVC has been overhauled to use
the new `catchpad` instruction. The filter function is now also a
rustc-generated function instead of a purely libstd-defined function. The
libstd definition still exists, it just has a stable ABI across architectures
and leaves some of the really weird implementation details to the compiler
(e.g. the `localescape` and `localrecover` intrinsics).
Alex Crichton [Fri, 23 Oct 2015 05:07:19 +0000 (22:07 -0700)]
trans: Upgrade LLVM
This brings some routine upgrades to the bundled LLVM that we're using, the most
notable of which is a bug fix to the way we handle range asserts when loading
the discriminant of an enum. This fix ended up being very similar to f9d4149c
where we basically can't have a range assert when loading a discriminant due to
filling drop, and appropriate flags were added to communicate this to
`trans::adt`.
bors [Fri, 29 Jan 2016 20:58:09 +0000 (20:58 +0000)]
Auto merge of #31283 - dotdash:32_64_cc, r=alexcrichton
When cross compiling for a target that has a larger usize type than the
host system, we use a truncated value to mark data as dropped,
eventually leading to drop calls on already dropped data. To properly
handle this, the drop pattern needs to be of type u64.
Since C_integral truncates its given value to the requested size anyway,
we can also drop the function that chose between the u32 and u64 values,
and always use the u64 constant.
Rollup merge of #31275 - alexcrichton:fix-rumprun, r=brson
Looks like the rumprun build has bitrotted over time, so this includes some libc
fixes and some various libstd fixes which gets it back to bootstrapping.
Rollup merge of #31264 - est31:block_coment_parent, r=alexcrichton
Block comments don't have to be in the format `/*! ... !*/`
in order to be read as doc comments about the parent block.
The format `/*! ... */` is enough.
Rollup merge of #31252 - alexcrichton:ios-old-mac, r=brson
Unfortunately older clang compilers don't support this argument, so the
bootstrap will fail. We don't actually really need to optimized the C code we
compile, however, as currently we're just compiling jemalloc and not much else.
bors [Fri, 29 Jan 2016 13:45:03 +0000 (13:45 +0000)]
Auto merge of #31212 - jseyfried:fix_ICE_in_resolve, r=nrc
This fixes an ICE introduced by #31065 that occurs when a path cannot be resolved because of a certain class of unresolved import (`Indeterminate` imports).
For example, this currently causes an ICE:
```rust
mod foo { pub use self::*; }
fn main() { foo::f() }
```
Björn Steinbrink [Thu, 28 Jan 2016 20:54:09 +0000 (21:54 +0100)]
Fix truncated drop pattern on 32bit -> 64bit cross compilation
When cross compiling for a target that has a larger usize type than the
host system, we use a truncated value to mark data as dropped,
eventually leading to drop calls on already dropped data. To properly
handle this, the drop pattern needs to be of type u64.
Since C_integral truncates its given value to the requested size anyway,
we can also drop the function that chose between the u32 and u64 values,
and always use the u64 constant.
bors [Fri, 29 Jan 2016 11:21:58 +0000 (11:21 +0000)]
Auto merge of #31144 - jseyfried:remove_import_ordering_restriction, r=nrc
We no longer require `use` and `extern crate` items to precede other items in modules thanks to [RFC #385](https://github.com/rust-lang/rfcs/pull/385), but we still require `use` and `extern crate` items to precede statements in blocks (other items can appear anywhere in a block).
I think that this is a needless distinction between imports and other items that contradicts the intent of the RFC.
Oliver Schneider [Thu, 28 Jan 2016 11:56:06 +0000 (12:56 +0100)]
don't leak RUST_BACKTRACE into test process
If the tests were run with `RUST_BACKTRACE=1 make check` this test failed. If they were run without it it succeeded.
We need to use `env_remove` instead of `env_clear` because the latter will never work on windows
bors [Fri, 29 Jan 2016 08:37:20 +0000 (08:37 +0000)]
Auto merge of #31132 - gchp:internals, r=brson
This adds the basic structure for the internals documentation, and also the initial version of the "Overview".
This first section gives and overview of the compilation process. It mentions the individual phases, and gives mention to their function & links to the relevant crates in the source tree.
This is a very general overview which is meant to lead in to the next section which will cover the `driver`. That section will give more in-depth information on each of the phases & cover things like sessions and the driver API. I wanted to give a more general introduction before getting into that detail.
bors [Fri, 29 Jan 2016 06:41:22 +0000 (06:41 +0000)]
Auto merge of #30948 - fabricedesre:rpi2, r=alexcrichton
This adds support for the armv7 crosstool-ng toolchain for the Raspberry Pi 2.
Getting the toolchain ready:
Checkout crosstool-ng from https://github.com/crosstool-ng/crosstool-ng
Build crosstool-ng
Configure the rpi2 target with |ct-ng armv7-rpi2-linux-gnueabihf|
Build the toolchain with |ct-build| and add the path to $toolchain_install_dir/bin to your $PATH
Then, on the rust side:
configure --target=armv7-rpi2-linux-gnueabihf && make && make install
To cross compile for the rpi2,
add $rust_install_path/lib to your $LD_LIBRARY_PATH, then use
rustc --target=armv7-rpi2-linux-gnueabihf -C linker=armv7-rpi2-linux-gnueabihf-g++ hello.rs
bors [Fri, 29 Jan 2016 03:41:44 +0000 (03:41 +0000)]
Auto merge of #30900 - michaelwoerister:trans_item_collect, r=nikomatsakis
The purpose of the translation item collector is to find all monomorphic instances of functions, methods and statics that need to be translated into LLVM IR in order to compile the current crate.
So far these instances have been discovered lazily during the trans path. For incremental compilation we want to know the set of these instances in advance, and that is what the trans::collect module provides.
In the future, incremental and regular translation will be driven by the collector implemented here.
This module is responsible for discovering all items that will contribute to
to code generation of the crate. The important part here is that it not only
needs to find syntax-level items (functions, structs, etc) but also all
their monomorphized instantiations. Every non-generic, non-const function
maps to one LLVM artifact. Every generic function can produce
from zero to N artifacts, depending on the sets of type arguments it
is instantiated with.
This also applies to generic items from other crates: A generic definition
in crate X might produce monomorphizations that are compiled into crate Y.
We also have to collect these here.
The following kinds of "translation items" are handled here:
The following things also result in LLVM artifacts, but are not collected
here, since we instantiate them locally on demand when needed in a given
codegen unit:
- Constants
- Vtables
- Object Shims
General Algorithm
-----------------
Let's define some terms first:
- A "translation item" is something that results in a function or global in
the LLVM IR of a codegen unit. Translation items do not stand on their
own, they can reference other translation items. For example, if function
`foo()` calls function `bar()` then the translation item for `foo()`
references the translation item for function `bar()`. In general, the
definition for translation item A referencing a translation item B is that
the LLVM artifact produced for A references the LLVM artifact produced
for B.
- Translation items and the references between them for a directed graph,
where the translation items are the nodes and references form the edges.
Let's call this graph the "translation item graph".
- The translation item graph for a program contains all translation items
that are needed in order to produce the complete LLVM IR of the program.
The purpose of the algorithm implemented in this module is to build the
translation item graph for the current crate. It runs in two phases:
1. Discover the roots of the graph by traversing the HIR of the crate.
2. Starting from the roots, find neighboring nodes by inspecting the MIR
representation of the item corresponding to a given node, until no more
new nodes are found.
The roots of the translation item graph correspond to the non-generic
syntactic items in the source code. We find them by walking the HIR of the
crate, and whenever we hit upon a function, method, or static item, we
create a translation item consisting of the items DefId and, since we only
consider non-generic items, an empty type-substitution set.
Given a translation item node, we can discover neighbors by inspecting its
MIR. We walk the MIR and any time we hit upon something that signifies a
reference to another translation item, we have found a neighbor. Since the
translation item we are currently at is always monomorphic, we also know the
concrete type arguments of its neighbors, and so all neighbors again will be
monomorphic. The specific forms a reference to a neighboring node can take
in MIR are quite diverse. Here is an overview:
The most obvious form of one translation item referencing another is a
function or method call (represented by a CALL terminator in MIR). But
calls are not the only thing that might introduce a reference between two
function translation items, and as we will see below, they are just a
specialized of the form described next, and consequently will don't get any
special treatment in the algorithm.
A function does not need to actually be called in order to be a neighbor of
another function. It suffices to just take a reference in order to introduce
an edge. Consider the following example:
fn main() {
let print_i32 = print_val::<i32>;
call_fn(&print_i32, 0);
}
```
The MIR of none of these functions will contain an explicit call to
`print_val::<i32>`. Nonetheless, in order to translate this program, we need
an instance of this function. Thus, whenever we encounter a function or
method in operand position, we treat it as a neighbor of the current
translation item. Calls are just a special case of that.
In a way, closures are a simple case. Since every closure object needs to be
constructed somewhere, we can reliably discover them by observing
`RValue::Aggregate` expressions with `AggregateKind::Closure`. This is also
true for closures inlined from other crates.
Drop glue translation items are introduced by MIR drop-statements. The
generated translation item will again have drop-glue item neighbors if the
type to be dropped contains nested values that also need to be dropped. It
might also have a function item neighbor for the explicit `Drop::drop`
implementation of its type.
A subtle way of introducing neighbor edges is by casting to a trait object.
Since the resulting fat-pointer contains a reference to a vtable, we need to
instantiate all object-save methods of the trait, as we need to store
pointers to these functions even if they never get called anywhere. This can
be seen as a special case of taking a function reference.
Since `Box` expression have special compiler support, no explicit calls to
`exchange_malloc()` and `exchange_free()` may show up in MIR, even if the
compiler will generate them. We have to observe `Rvalue::Box` expressions
and Box-typed drop-statements for that purpose.
Interaction with Cross-Crate Inlining
-------------------------------------
The binary of a crate will not only contain machine code for the items
defined in the source code of that crate. It will also contain monomorphic
instantiations of any extern generic functions and of functions marked with
The collection algorithm handles this more or less transparently. When
constructing a neighbor node for an item, the algorithm will always call
`inline::get_local_instance()` before proceeding. If no local instance can
be acquired (e.g. for a function that is just linked to) no node is created;
which is exactly what we want, since no machine code should be generated in
the current crate for such an item. On the other hand, if we can
successfully inline the function, we subsequently can just treat it like a
local item, walking it's MIR et cetera.
Eager and Lazy Collection Mode
------------------------------
Translation item collection can be performed in one of two modes:
- Lazy mode means that items will only be instantiated when actually
referenced. The goal is to produce the least amount of machine code
possible.
- Eager mode is meant to be used in conjunction with incremental compilation
where a stable set of translation items is more important than a minimal
one. Thus, eager mode will instantiate drop-glue for every drop-able type
in the crate, even of no drop call for that type exists (yet). It will
also instantiate default implementations of trait methods, something that
otherwise is only done on demand.
Open Issues
-----------
Some things are not yet fully implemented in the current version of this
module.
Since no MIR is constructed yet for initializer expressions of constants and
statics we cannot inspect these properly.
Ideally, no translation item should be generated for const fns unless there
is a call to them that cannot be evaluated at compile time. At the moment
this is not implemented however: a translation item will be produced
regardless of whether it is actually needed or not.
Alex Crichton [Fri, 29 Jan 2016 03:33:29 +0000 (19:33 -0800)]
std: Fix rumprun build
Looks like the rumprun build has bitrotted over time, so this includes some libc
fixes and some various libstd fixes which gets it back to bootstrapping.
Rustdoc could trigger a code path that relied on the
$CFG_COMPILER_HOST_TRIPLE environment variable being
set, causing an ICE if it was not. This fixes that,
emitting an error instead of crashing.
est31 [Thu, 28 Jan 2016 17:39:39 +0000 (18:39 +0100)]
Fix reference info about parent doc block comments
Block comments don't have to be in the format `/*! ... !*/`
in order to be read as doc comments about the parent block.
The format `/*! ... */` is enough.
Alex Crichton [Thu, 28 Jan 2016 06:34:26 +0000 (22:34 -0800)]
mk: Remove the -mfpu=vfp4 argument from arm iOS
Unfortunately older clang compilers don't support this argument, so the
bootstrap will fail. We don't actually really need to optimized the C code we
compile, however, as currently we're just compiling jemalloc and not much else.
Rollup merge of #31186 - gchp:contributing, r=alexcrichton
I recently wrote a blog post on contributing to the Rust compiler which
gained some interest. It was mentioned in a comment on Reddit that it
would be useful to integrate some of the information from that post to
the official contributing guide.
This is the start of my efforts to integrate what I wrote with the
official guide.
This commit adds information on the build system. It is not a complete
guide on the build system, but it should be enough to provide a good
starting place for those wishing to contribute.
bors [Wed, 27 Jan 2016 16:25:36 +0000 (16:25 +0000)]
Auto merge of #31224 - bluss:deque-hashing, r=Gankro
Hash VecDeque in its slice parts
Use .as_slices() for a more efficient code path in VecDeque's Hash impl.
This still hashes the elements in the same order.
Before/after timing of VecDeque hashing 1024 elements of u8 and
u64 shows that the vecdeque now can match the Vec
(test_hashing_vec_of_u64 is the Vec run).
bors [Wed, 27 Jan 2016 12:12:52 +0000 (12:12 +0000)]
Auto merge of #31089 - fhahn:macro-ice, r=pnkfelix
This is a work in progress PR that potentially should fix #29084, #28308, #25385, #28288, #31011. I think this may also adresse parts of #2887.
The problem in this issues seems to be that when transcribing macro arguments, we just clone the argument Nonterminal, which still has to original spans. This leads to the unprintable spans. One solution would be to update the spans of the inserted argument to match the argument in the macro definition. So for [this testcase](https://github.com/rust-lang/rust/compare/master...fhahn:macro-ice?expand=1#diff-f7def7420c51621640707b6337726876R2) the error message would be displayed in the macro definition:
src/test/compile-fail/issue-31011.rs:4:12: 4:22 error: attempted access of field `trace` on type `&T`, but no field with that name was found
src/test/compile-fail/issue-31011.rs:4 if $ctx.trace {
Currently I've added a very simple `update_span` function, which updates the span of the outer-most expression of a `NtExpr`, but this `update_span` function should be updated to handle all Nonterminals. But I'm pretty new to the macro system and would like to check if this approach makes sense, before doing that.
bors [Wed, 27 Jan 2016 03:30:14 +0000 (03:30 +0000)]
Auto merge of #30859 - aliclark:musl-nx-issue, r=brson
This explicitly adds an option telling the linker on these platforms to make the stack and heap non-executable (should already be the case for Windows, and likely OS X).
Without this option there is some risk of accidentally losing NX protection, as the linker will not enable NX if any of the binary's constituent objects don't contain the .note.GNU-stack header.
We're not aware of any users who would want a binary with executable stack or heap, but in future this could be made possible by passing a flag to disable the protection, which would also help document the fact to the crate's users.
Edit: older discussion of previous quickfix to add a .note.GNU-stack header to libunwind's assembly:
Short term solution for issue #30824 to ensure that object files generated from assembler contain the .note.GNU-stack header.
When this header is not present in any constituent object files, the linker refrains from making the stack NX in the final executable.
Further actions:
I'll try to get this change merged in with upstream too, and then update these instructions to just compile the fixed version.
It seems a good idea to use issue #30824 or some other issue to add a test that similar security regressions can be automatically caught in future.
Ulrik Sverdrup [Tue, 26 Jan 2016 20:31:33 +0000 (21:31 +0100)]
collections: Hash VecDeque in its slice parts
Use .as_slices() for a more efficient code path in VecDeque's Hash impl.
This still hashes the elements in the same order.
Before/after timing of VecDeque hashing 1024 elements of u8 and
u64 shows that the vecdeque now can match the Vec
(test_hashing_vec_of_u64 is the Vec run).
bors [Tue, 26 Jan 2016 22:10:10 +0000 (22:10 +0000)]
Auto merge of #31120 - alexcrichton:attribute-deny-warnings, r=brson
This commit removes the `-D warnings` flag being passed through the makefiles to
all crates to instead be a crate attribute. We want these attributes always
applied for all our standard builds, and this is more amenable to Cargo-based
builds as well.
Note that all `deny(warnings)` attributes are gated with a `cfg(stage0)`
attribute currently to match the same semantics we have today
bors [Tue, 26 Jan 2016 19:30:54 +0000 (19:30 +0000)]
Auto merge of #31081 - alexcrichton:stabilize-hasher, r=aturon
This commit implements the stabilization of the custom hasher support intended
for 1.7 but left out due to some last-minute questions that needed some
decisions. A summary of the actions done in this PR are:
* `std::collections::hash_state`
* `std::collections::hash_state::HashState` - this trait was also moved into
`std::hash` with a reexport here to ensure that we can have a blanket impl to
prevent immediate breakage on nightly. Note that this is unstable in both
location.
* `HashMap::with_hash_state` - renamed
* `HashMap::with_capacity_and_hash_state` - renamed
* `HashSet::with_hash_state` - renamed
* `HashSet::with_capacity_and_hash_state` - renamed
bors [Tue, 26 Jan 2016 16:50:27 +0000 (16:50 +0000)]
Auto merge of #30402 - jooert:prettypanic, r=alexcrichton
This splits the output of panics into two lines as proposed in #15239 and adds a
note about how to get a backtrace. Because the default panic message consists of
multiple lines now, this changes the test runner's failure output to not indent
the first line anymore.
Alex Crichton [Thu, 21 Jan 2016 18:28:39 +0000 (10:28 -0800)]
std: Stabilize custom hasher support in HashMap
This commit implements the stabilization of the custom hasher support intended
for 1.7 but left out due to some last-minute questions that needed some
decisions. A summary of the actions done in this PR are:
* `std::collections::hash_state`
* `std::collections::hash_state::HashState` - this trait was also moved into
`std::hash` with a reexport here to ensure that we can have a blanket impl to
prevent immediate breakage on nightly. Note that this is unstable in both
location.
* `HashMap::with_hash_state` - renamed
* `HashMap::with_capacity_and_hash_state` - renamed
* `HashSet::with_hash_state` - renamed
* `HashSet::with_capacity_and_hash_state` - renamed
The purpose of the translation item collector is to find all monomorphic instances of functions, methods and statics that need to be translated into LLVM IR in order to compile the current crate.
So far these instances have been discovered lazily during the trans path. For incremental compilation we want to know the set of these instances in advance, and that is what the trans::collect module provides.
In the future, incremental and regular translation will be driven by the collector implemented here.
Rollup merge of #31177 - alexcrichton:no-stdio, r=sfackler
On all platforms, reading from stdin where the actual stdin isn't present should
return 0 bytes as having been read rather than the entire buffer.
On Windows, handle the case where we're inheriting stdio handles but one of them
isn't present. Currently the behavior is to fail returning an I/O error but
instead this commit corrects it to detecting this situation and propagating the
non-set handle.
Rollup merge of #31172 - SimonSapin:patch-17, r=sfackler
The previous example did not do what its description said. In it panicked on integer overflow in debug mode, and went into an infinite loop in release mode (wrapping back to 0 after printing 254).
Simon Sapin [Sun, 24 Jan 2016 23:56:34 +0000 (00:56 +0100)]
RangeFrom::step_by docs: fix example
The previous example did not do what its description said. In it panicked on integer overflow in debug mode, and went into an infinite loop in release mode (wrapping back to 0 after printing 254).
bors [Tue, 26 Jan 2016 11:24:18 +0000 (11:24 +0000)]
Auto merge of #31105 - jseyfried:fix_lexical_scoping, r=nrc
This fixes #23880, a scoping bug in which items in a block are shadowed by local variables and type parameters that are in scope.
After this PR, an item in a block will shadow any local variables or type parameters above the item in the scope hierarchy. Items in a block will continue to be shadowed by local variables in the same block (even if the item is defined after the local variable).
This is a [breaking-change]. For example, the following code breaks:
```rust
fn foo() {
let mut f = 1;
{
fn f() {}
f += 1; // This will resolve to the function instead of the local variable
}
}