The way we deal with unreachable expressions in trans is pretty ad hoc,
but this at least doesn't make it worse, and eliminates the LLVM
assertion failure reported in #5741.
This adds a lint mode for detecting unnecessary allocations on the heap. This isn't super fancy, currently it only has two rules
1. For a function's arguments, if you allocate a `[~|@]str` literal, when the type of the argument is a `&str`, emit a warning.
2. For the same case, emit warnings for boxed vectors when slices are required.
After adding the lint, I rampaged through the libraries and removed all the unnecessary allocations I could find.
With this, the build is almost 100% warning free.
One more can be fixed after the next snapshot, and there's one other that I filed an issue about already.
r? @nikomatsakis Impls can implement either zero or one traits; this has been true
more or less since we removed classes. So I got rid of the comments
saying "we should support multiple traits" and changed the code to
make it clear that we don't. This is just cleanup, and doesn't break
any existing tests.
Impls can implement either zero or one traits; this has been true
more or less since we removed classes. So I got rid of the comments
saying "we should support multiple traits" and changed the code to
make it clear that we don't. This is just cleanup, and doesn't break
any existing tests.
fail!() used to require owned strings but can handle static strings
now. Also, it can pass its arguments to fmt!() on its own, no need for
the caller to call fmt!() itself.
This pull request adds 4 atomic intrinsics to the compiler, in preparation for #5042.
* `atomic_load(src: &int) -> int` performs an atomic sequentially consistent load.
* `atomic_load_acq(src: &int) -> int` performs an atomic acquiring load.
* `atomic_store(dst: &mut int, val: int)` performs an atomic sequentially consistent store.
* `atomic_store_rel(dst: &mut int, val: int)` performs an atomic releasing store.
For more information about the whole acquire/release thing: http://llvm.org/docs/Atomics.html
r?
The default versions (atomic_load and atomic_store) are sequentially consistent.
The atomic_load_acq intrinsic acquires as described in [1].
The atomic_store_rel intrinsic releases as described in [1].
[1]: http://llvm.org/docs/Atomics.html
Closes#6183.
The first commit changes the compiler's method of treating a `for` loop, and all the remaining commits are just dealing with the fallout.
The biggest fallout was the `IterBytes` trait, although it's really a whole lot nicer now because all of the `iter_bytes_XX` methods are just and-ed together. Sadly there was a huge amount of stuff that's `cfg(stage0)` gated, but whoever lands the next snapshot is going to have a lot of fun deleting all this code!
&str can be turned into @~str on demand, using to_owned(), so for
strings, we can create a specialized interner that accepts &str for
intern() and find() but stores and returns @~str.
Use a bitset to represent built-in bounds. There are several places in the language where only builtin bounds (aka kinds) will be accepted, e.g. on closures, destructor type parameters perhaps, and on trait types.
r? @brson
Fix#6355 and #6272---we were not giving the correct index to the derefs that occur as part of the rooting process, resulting in extra copies and generally bogus behavior. Haven't quite produced the right test for this, but I thought I'd push the fix in the meantime. Test will follow shortly.
r? @graydon
Adds an `uninit` intrinsic.
It's just an empty function, so llvm optimizes it down to nothing.
I changed all of the `init` intrinsic usages to `uninit` where it seemed appropriate to.
its own type. Use a bitset to represent built-in bounds. There
are several places in the language where only builtin bounds (aka kinds)
will be accepted, e.g. on closures, destructor type parameters perhaps,
and on trait types.
&str can be turned into @~str on demand, using to_owned(), so for
strings, we can create a specialized interner that accepts &str for
intern() and find() but stores and returns @~str.
Hi there,
Really enjoying Rust. Noticed a few typos so I searched around for a few more--here's some fixes.
Ran `make check` and got `summary of 24 test runs: 4868 passed; 0 failed; 330 ignored`.
Thanks!
Sean
At the moment this only includes type checking and there is no code generation support yet. I wanted to get the design reviewed first.
From discussion with @graydon at #5841, re-implemented as `#[simd]` attribute on structs.
Progressing towards #3499.
I just had `git apply` fix most of them and then did a quick skim over the diff to fix a few cases where it did the wrong thing (mostly replacing tabs with 4 spaces, when someone's editor had them at 8 spaces).
Recent demoding makes the visitor glue leak. It hasn't shown up in tests
because the box annihilator deletes the leaked boxes. This affects the
new scheduler though which does not yet have a box annihilator.
I don't think there's any great way to test this besides setting up
a task that doesn't run the box annihilator and I don't know that that's
a capability we want tasks to have.
I don't know how one would write a separate test for this sort of thing. Building the compiler, and `make check` worked, which should mean I didn't screw anything.
I've added trt_field_vtable, trt_field_box, and trt_field_tydesc, and
inserted them in place of the "magic numbers" used to access trait
object fields through GEPi().
The drop block has been deprecated for quite some time. This patch series removes support for parsing it and all the related machinery that made drop work.
As a side feature of all this, I also added the ability to annote fields in structs. This allows comments to be properly associated with an individual field. However, I didn't update `rustdoc` to integrate these comment blocks into the documentation it generates.
Cases like `Either<@int,()>` have a null case with at most one value but
a nonzero number of fields; if we misreport this, then bad things can
happen inside of, for example, pattern matching.
Closes#6117.
Closes#3083.
This takes a similar approach to #5797 where a set is present on the `tcx` of used mutable definitions. Everything is by default warned about, and analyses must explicitly add mutable definitions to this set so they're not warned about.
Most of this was pretty straightforward, although there was one caveat that I ran into when implementing it. Apparently when the old modes are used (or maybe `legacy_modes`, I'm not sure) some different code paths are taken to cause spurious warnings to be issued which shouldn't be issued. I'm not really sure how modes even worked, so I was having a lot of trouble tracking this down. I figured that because they're a legacy thing that I'd just de-mode the compiler so that the warnings wouldn't be a problem anymore (or at least for the compiler).
Other than that, the entire compiler compiles without warnings of unused mutable variables. To prevent bad warnings, #5965 should be landed (which in turn is waiting on #5963) before landing this. I figured I'd stick it out for review anyway though.
As the name suggests this replaces many instances of cast::reinterpret_cast by cast::transmute. It's essentially the boring part of fixing #5163, the remaining reinterpret_casts should be more tricky to remove (unless I missed a boring case).
r? @catamorphism
This adds debugging symbol generation for boxes, bare functions, vectors, and strings, along with a tests for boxes and vectors.
Note that gdb will see them as their actual compiled representation with the refcount, tydesc, etc. fields, so if `b` refers to box, `b->boxed` will refer to its value. Also, since you seem to use the [C struct hack](http://c-faq.com/struct/structhack.html) for dynamic vectors, you won't be able to print out the whole vector at once, only one element at a time by indexing specific elements.
r? @nikomatsakis
This doesn't completely fix the x86 ABI for structs, but it does fix some cases. On linux, structs appear to be returned correctly now. On windows, structs are only returned by pointer when they are greater than 8 bytes. That scenario works now.
In the case where the struct is less than 8 bytes our generated code looks peculiar. When returning a pair of u16, C packs both variables into %eax to return them. Our generated code though expects to find one of the pair in %ax and the other in %dx. Similar for u8. I haven't looked into it yet.
There appears to also be struct passing problems on linux, where my `extern-pass-TwoU8s` and `extern-pass-TwoU16s` tests are failing.
This Adds a bunch of tests for passing and returning structs
of various sizes to C. It fixes the struct return rules on unix,
and on windows for structs of size > 8 bytes. Struct passing
on unix for structs under a certain size appears to still be broken.
Closes#5487, #1913, and #4568
I tracked this by adding all used unsafe blocks/functions to a set on the `tcx` passed around, and then when the lint pass comes around if an unsafe block/function isn't listed in that set, it's unused.
I also removed everything from the compiler that was unused, and up to stage2 is now compiling without any known unused unsafe blocks.
I chose `unused_unsafe` as the name of the lint attribute, but there may be a better name...
This takes care of one of the last remnants of assumptions about enum layout. A type visitor is now passed a function to read a value's discriminant, then accesses fields by being passed a byte offset for each one. The latter may not be fully general, despite the constraints imposed on representations by borrowed pointers, but works for any representations currently planned and is relatively simple.
Closes#5652.
This implements #5158. Currently it takes the command line args and the crate map. Since it doesn't take a `main` function pointer, you can't actually start the runtime easily, but that seems to be a shim to allow the current `rust_start` function to call into main.
However, you can do an end-run round the io library and do this:
```rust
use core::libc::{write, c_int, c_void, size_t, STDOUT_FILENO};
#[start]
fn my_start(_argc:int, _argv: **u8, _crate_map: *u8) -> int {
do str::as_buf("Hello World!\n") |s,len| {
unsafe {
write(STDOUT_FILENO, s as *c_void, len as size_t);
}
}
return 0;
}
```
Which is the most basic "Hello World" you can do in rust without starting up the runtime (though that has quite a lot to do with the fact that `core::io` uses `@` everywhere...)
Revert map.each to something which takes two parameters rather than a tuple. The current setup iterates over `BaseIter<(&'self K, &'self V)>` where 'self is a lifetime declared *in the `each()` method*. You can't place such a type in the impl declaration. The compiler currently allows it, but this will not be legal under #5656 and I'm pretty sure it's not sound now. It's too bad that maps can't implement `BaseIter` (at least not over a tuple as they do here) but I think it has to be this way for the time being.
r? @thestinger
rather than a tuple. The current setup iterates over
`BaseIter<(&'self K, &'self V)>` where 'self is a lifetime declared
*in the each method*. You can't place such a type in
the impl declaration. The compiler currently allows it,
but this will not be legal under #5656 and I'm pretty sure
it's not sound now.
A struct (inc. tuple struct) can be annotated with #[packed], so that there
is no padding between its elements, like GCC's `__attribute__((packed))`.
Closes#1704
- In a TraitRef, use the self type consistently to refer to the Self type:
- trait ref in `impl Trait<A,B,C> for S` has a self type of `S`.
- trait ref in `A:Trait` has the self type `A`
- trait ref associated with a trait decl has self type `Self`
- trait ref associated with a supertype has self type `Self`
- trait ref in an object type `@Trait` has no self type
- Rewrite `each_bound_traits_and_supertraits` to perform
substitutions as it goes, and thus yield a series of trait refs
that are always in the same 'namespace' as the type parameter
bound given as input. Before, we left this to the caller, but
this doesn't work because the caller lacks adequare information
to perform the type substitutions correctly.
- For provided methods, substitute the generics involved in the provided
method correctly.
- Introduce TypeParameterDef, which tracks the bounds declared on a type
parameter and brings them together with the def_id and (in the future)
other information (maybe even the parameter's name!).
- Introduce Subst trait, which helps to cleanup a lot of the
repetitive code involved with doing type substitution.
- Introduce Repr trait, which makes debug printouts far more convenient.
Fixes#4183. Needed for #5656.
bare function store (which is not in fact a kind of value) but rather
ty::TraitRef. Removes many uses of fail!() and other telltale signs of
type-semantic mismatch.
cc #4183 (not a fix, but related)
I believe this patch incorporates all expected syntax changes from extern
function reform (#3678). You can now write things like:
extern "<abi>" fn foo(s: S) -> T { ... }
extern "<abi>" mod { ... }
extern "<abi>" fn(S) -> T
The ABI for foreign functions is taken from this syntax (rather than from an
annotation). We support the full ABI specification I described on the mailing
list. The correct ABI is chosen based on the target architecture.
Calls by pointer to C functions are not yet supported, and the Rust type of
crust fns is still *u8.
Before it wouldn't warn about unused imports in the list if something in the list was used. These commits fix that case, add a test, and remove all unused imports in lists of imports throughout the compiler.
re bug that @nikomatsakis was hitting: when you define a `static` (old: `const`) containing a `&` or `&[]` expression, it will create temporaries (the underlying pointee) by creating a throwaway symbol for each temporary, each with _global_ linkage, and each named `"const"`. LLVM will helpfully rename multiple copies of this throwaway symbol to `"const1"` and `"const2"` and so forth in the _same_ library. But if you have _2 libraries_ -- say, libcore and librustc -- that both do this, the dynamic linker (at least on linux) will happily do horrible things like make the slice in one library point to the bytes of the vector from the other library. This is obviously a recipe for much hilarity and head-scratching.
The solution is to change the linkage to something else, internal or (in the case of this patch) _private_.
It will require a snapshot to integrate this into stage0 and thereby fix the problem / unblock patches that were hitting this in stage1.
Hey folks,
This patch series does some work on the json decoder, specifically with auto decoding of enums. Previously, we would take this code:
```
enum A {
B,
C(~str, uint)
}
```
and would encode a value of this enum to either `["B", []]` or `["C", ["D", 123]]`. I've changed this to `"B"` or `["C", "D", 123]`. This matches the style of the O'Caml json library [json-wheel](http://mjambon.com/json-wheel.html). I've added tests to make sure all this work.
In order to make this change, I added passing a `&[&str]` vec to `Decode::emit_enum_variant` so the json decoder can convert the name of a variant into it's position. I also changed the impl of `Encodable` for `Option<T>` to have the right upper casing.
I also did some work on the parser, which allows for `fn foo<T: ::cmp::Eq>() { ... }` statements (#5572), fixed the pretty printer properly expanding `debug!("...")` expressions, and removed `ast::expr_vstore_fixed`, which doesn't appear to be used anymore.
the types. Initially I thought it would be necessary to thread this data
through not only the AST but the types themselves, but then I remembered that
the pretty printer only cares about the AST. Regardless, I have elected to
leave the changes to the types intact since they will eventually be needed. I
left a few FIXMEs where it didn't seem worth finishing up since the code wasn't
crucial yet.
Various FIXME comments added around to denote copies which when removed cause
the compiler to segfault at some point before stage2. None of these copies
should even be necessary.
and from typeck, which is verboten. We are supposed to write inference results
into the FnCtxt and then these get copied over in writeback. Add assertions
that no inference by-products are added to this table.
Fixes#3888Fixes#4036Fixes#4492
r? @nikomatsakis The typechecker previously passed around a boolean return flag to
indicate whether it saw something with type _|_ (that is, something
it knows at compile-time will definitely diverge) and also had some
manual checks for the `ty_err` pseudo-type that represents a previous
type error. This was because the typing rules implemented by the
typechecker didn't properly propagate _|_ and ty_err. I fixed it.
This also required changing expected error messages in a few tests,
as now we're printing out fewer derived errors -- in fact, at this
point we should print out no derived errors, so report any that
you see (ones that include "[type error]") as bugs.
The typechecker previously passed around a boolean return flag to
indicate whether it saw something with type _|_ (that is, something
it knows at compile-time will definitely diverge) and also had some
manual checks for the `ty_err` pseudo-type that represents a previous
type error. This was because the typing rules implemented by the
typechecker didn't properly propagate _|_ and ty_err. I fixed it.
This also required changing expected error messages in a few tests,
as now we're printing out fewer derived errors -- in fact, at this
point we should print out no derived errors, so report any that
you see (ones that include "[type error]") as bugs.
Removes a lot of instances of `/*bad*/ copy` throughout libsyntax/librustc. On the plus side, this shaves about 2s off of the runtime when compiling `librustc` with optimizations.
Ideally I would have run a profiler to figure out which copies are the most critical to remove, but in reality there was a liberal amount of `git grep`s along with some spot checking and removing the easy ones.
For bootstrapping purposes, this commit does not remove all uses of
the keyword "pure" -- doing so would cause the compiler to no longer
bootstrap due to some syntax extensions ("deriving" in particular).
Instead, it makes the compiler ignore "pure". Post-snapshot, we can
remove "pure" from the language.
There are quite a few (~100) borrow check errors that were essentially
all the result of mutable fields or partial borrows of `@mut`. Per
discussions with Niko I think we want to allow partial borrows of
`@mut` but detect obvious footguns. We should also improve the error
message when `@mut` is erroneously reborrowed.
This is done in two steps:
First, we make foreign functions not consider modes at all. This is because previously ++ mode was the only way to pass structs to foreign functions and so forth. We also add a lint mode warning if you use `&&` mode in a foreign function, since the semantics of that change (it used to pass a pointer to the C function, now it doesn't).
Then, we remove by value and make it equivalent to `+` mode. At the same time, we stop parsing `-` mode and convert all uses of it to `+` mode (it was already being parsed to `+` mode anyhow).
This obsoletes pull request #5298.
r? @brson
adjusting a few foreign functions that were declared with by-ref
mode. This also allows us to remove by-val mode in the near future.
With copy mode, though, we have to be careful because Rust will implicitly pass
somethings by pointer but this may not be the C ABI rules. For example, rust
will pass a struct Foo as a Foo*. So I added some code into the adapters to
fix this (though the C ABI rules may put the pointer back, oh well).
This patch also includes a lint mode for the use of by-ref mode
in foreign functions as the semantics of this have changed.
Continuing #5140
For the sake of getting this merged I've disabled debuginfo tests on mac (where running gdb needs root). Please feel free to follow up with further improvements.
r? @graydon
This removes `log` from the language. Because we can't quite implement it as a syntax extension (probably need globals at the least) it simply renames the keyword to `__log` and hides it behind macros.
After this the only way to log is with `debug!`, `info!`, etc. I figure that if there is demand for `log!` we can add it back later.
I am not sure that we ever agreed on this course of action, though I *think* there is consensus that `log` shouldn't be a statement.
These changes make const translation use adjustments (autodereference, autoreference, bare-fn-to-closure), like normal code does, replacing some ad-hoc logic that wasn't always right.
As a convenient side-effect, explicit dereference (both of pointers and of newtypes) is also supported in const expressions.
There is also a “bonus fix” for a bug in the pretty-printer exposed by one of the added tests.
Struct and enum representations have some complicatedness that's no longer needed. Now that everything's in one place and has access to anything we'd want to know about the type, flatten some of that out. Slight changes to representations in some cases.
The only thing we really lose is that C-like enums with one variant and a
non-zero discriminant now take up space, but I do not think this is a
common usage. As previously noted, that was mostly there for
transitional compatibility with the pre-adt.rs codebase.
Out goes the extra layer of struct wrapping; the destructedness flag is
added to the end of the struct. This means that, if the struct
previously had alignment padding at the end, the flag will live there
instead of increasing the struct size.
Changes the ad-hoc closure adjustment into using adjustment info instead
of being separately driven from types, and likewise for autoderef.
Also takes care of autoref (the cases we should be seeing in consts,
at least, since we can't be doing method calls which would need the
ref-to-vec mode), which didn't quite work right previously.
However, "dereference" of a newtype isn't handled yet....
