borrow checker and generalize what moves are allowed. Fixes a nasty
bug or two in the pattern move checking code. Unifies dataflow code
used for initialization and other things. First step towards
once fns. Everybody wins.
Fixes#4384. Fixes#4715. cc once fns (#2202), optimizing local moves (#5016).
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.
Currently, trait_info is a hashmap that allows a quick lookup of all
methods contained in a given trait, but we actually only use it to
lookup traits that contain a given method. Adjusting the map to support
the lookup we actually need gives a nice speed boost, reducing the time
required for the resolution step for librustc from ~2.6s to ~1.0s on my
box.
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.
Every unresolved import is reported. An additional error message isn't useful
and obscures (imo) the real errors: I need to take it into account when
looking at the error count.
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.
This improves error reporting for the following class of imports:
```rust
use foo::bar;
```
Where foo, the topmost module, is unresolved. It now results in:
```text
/tmp/foo.rs:1:4: 1:7 error: unresolved import. perhapsyou forgot an 'extern mod foo'?
/tmp/foo.rs:1 use foo::bar;
^~~
/tmp/foo.rs:1:4: 1:12 error: failed to resolve import: foo::bar
/tmp/foo.rs:1 use foo::bar;
^~~~~~~~
error: failed to resolve imports
error: aborting due to 3 previous errors
```
This is the first of a series of changes I plan on making to unresolved name error messages.
&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.
r? @ILyoan
This pulls all the logic for discovering the crate entry point into a new pass (out of resolve and typeck), then changes it so that main is only looked for at the crate level (`#[main]` can still be used anywhere).
I don't understand the special android logic here and worry that I may have broken it.
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.
I didn't know how to use "use" initially, and an error message like this would
have solved quite a bit of frustration. I think this properly handles cases
where it's not appropriate but I'm not sure.
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.
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...)
There's no unifying theme here; I'm just trying to clear a bunch of small commits: removing dead code, adding comments, renaming to an upper-case type, fixing one test case.
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.
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, if anything in a list was used, the entire list was considered to be
used. This corrects this and also warns on a span of the actual unused import
instead of the entire list.
Impose a limit so that the typo suggester only shows reasonable
suggestions (i.e. don't suggest `args` when the error is `foobar`).
A tiny bit of progress on #2281.
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.
Major changes are:
- replace ~[ty_param] with Generics structure, which includes
both OptVec<TyParam> and OptVec<Lifetime>;
- the use of syntax::opt_vec to avoid allocation for empty lists;
cc #4846
