This commit is an implementation of [RFC 1183][rfc] which allows swapping out
the default allocator on nightly Rust. No new stable surface area should be
added as a part of this commit.
[rfc]: https://github.com/rust-lang/rfcs/pull/1183
Two new attributes have been added to the compiler:
* `#![needs_allocator]` - this is used by liballoc (and likely only liballoc) to
indicate that it requires an allocator crate to be in scope.
* `#![allocator]` - this is a indicator that the crate is an allocator which can
satisfy the `needs_allocator` attribute above.
The ABI of the allocator crate is defined to be a set of symbols that implement
the standard Rust allocation/deallocation functions. The symbols are not
currently checked for exhaustiveness or typechecked. There are also a number of
restrictions on these crates:
* An allocator crate cannot transitively depend on a crate that is flagged as
needing an allocator (e.g. allocator crates can't depend on liballoc).
* There can only be one explicitly linked allocator in a final image.
* If no allocator is explicitly requested one will be injected on behalf of the
compiler. Binaries and Rust dylibs will use jemalloc by default where
available and staticlibs/other dylibs will use the system allocator by
default.
Two allocators are provided by the distribution by default, `alloc_system` and
`alloc_jemalloc` which operate as advertised.
Closes#27389
To correctly reexport statically included libraries from a DLL on Windows, the
compiler will soon need to have knowledge about what symbols are statically
included and which are not. To solve this problem a new unstable
`#[linked_from]` attribute is being added and recognized on `extern` blocks to
indicate which native library the symbols are coming from.
The compiler then keeps track of what the set of FFI symbols are that are
included statically. This information will be used in a future commit to
configure how we invoke the linker on Windows.
This search happens a lot! Locally, compiling hyper sees the following improvements:
before
real 0m30.843s
user 0m51.644s
sys 0m2.128s
real 0m30.164s
user 0m53.320s
sys 0m2.208s
after
real 0m28.438s
user 0m51.076s
sys 0m2.276s
real 0m28.612s
user 0m51.560s
sys 0m2.192s
Many of these have long since reached their stage of being obsolete, so this
commit starts the removal process for all of them. The unstable features that
were deprecated are:
* cmp_partial
* fs_time
* hash_default
* int_slice
* iter_min_max
* iter_reset_fuse
* iter_to_vec
* map_in_place
* move_from
* owned_ascii_ext
* page_size
* read_and_zero
* scan_state
* slice_chars
* slice_position_elem
* subslice_offset
This commit is an implementation of [RFC 1044][rfc] which adds additional
surface area to the `std::fs` module. All new APIs are `#[unstable]` behind
assorted feature names for each one.
[rfc]: https://github.com/rust-lang/rfcs/pull/1044
The new APIs added are:
* `fs::canonicalize` - bindings to `realpath` on unix and
`GetFinalPathNameByHandle` on windows.
* `fs::symlink_metadata` - similar to `lstat` on unix
* `fs::FileType` and accessor methods as `is_{file,dir,symlink}`
* `fs::Metadata::file_type` - accessor for the raw file type
* `fs::DirEntry::metadata` - acquisition of metadata which is free on Windows
but requires a syscall on unix.
* `fs::DirEntry::file_type` - access the file type which may not require a
syscall on most platforms.
* `fs::DirEntry::file_name` - access just the file name without leading
components.
* `fs::PathExt::symlink_metadata` - convenience method for the top-level
function.
* `fs::PathExt::canonicalize` - convenience method for the top-level
function.
* `fs::PathExt::read_link` - convenience method for the top-level
function.
* `fs::PathExt::read_dir` - convenience method for the top-level
function.
* `std::os::raw` - type definitions for raw OS/C types available on all
platforms.
* `std::os::$platform` - new modules have been added for all currently supported
platforms (e.g. those more specific than just `unix`).
* `std::os::$platform::raw` - platform-specific type definitions. These modules
are populated with the bare essentials necessary for lowing I/O types into
their raw representations, and currently largely consist of the `stat`
definition for unix platforms.
This commit also deprecates `Metadata::{modified, accessed}` in favor of
inspecting the raw representations via the lowering methods of `Metadata`.
Closes https://github.com/rust-lang/rust/issues/24796
This commit is an implementation of [RFC 1044][rfc] which adds additional
surface area to the `std::fs` module. All new APIs are `#[unstable]` behind
assorted feature names for each one.
[rfc]: https://github.com/rust-lang/rfcs/pull/1044
The new APIs added are:
* `fs::canonicalize` - bindings to `realpath` on unix and
`GetFinalPathNameByHandle` on windows.
* `fs::symlink_metadata` - similar to `lstat` on unix
* `fs::FileType` and accessor methods as `is_{file,dir,symlink}`
* `fs::Metadata::file_type` - accessor for the raw file type
* `fs::DirEntry::metadata` - acquisition of metadata which is free on Windows
but requires a syscall on unix.
* `fs::DirEntry::file_type` - access the file type which may not require a
syscall on most platforms.
* `fs::DirEntry::file_name` - access just the file name without leading
components.
* `fs::PathExt::symlink_metadata` - convenience method for the top-level
function.
* `fs::PathExt::canonicalize` - convenience method for the top-level
function.
* `fs::PathExt::read_link` - convenience method for the top-level
function.
* `fs::PathExt::read_dir` - convenience method for the top-level
function.
* `std::os::raw` - type definitions for raw OS/C types available on all
platforms.
* `std::os::$platform` - new modules have been added for all currently supported
platforms (e.g. those more specific than just `unix`).
* `std::os::$platform::raw` - platform-specific type definitions. These modules
are populated with the bare essentials necessary for lowing I/O types into
their raw representations, and currently largely consist of the `stat`
definition for unix platforms.
This commit also deprecates `Metadata::{modified, accessed}` in favor of
inspecting the raw representations via the lowering methods of `Metadata`.
- Functions in parser.rs return PResult<> rather than panicing
- Other functions in libsyntax call panic! explicitly for now if they rely on panicing behaviour.
- 'panictry!' macro added as scaffolding while converting panicing functions.
(This does the same as 'unwrap()' but is easier to grep for and turn into try!())
- Leaves panicing wrappers for the following functions so that the
quote_* macros behave the same:
- parse_expr, parse_item, parse_pat, parse_arm, parse_ty, parse_stmt
This commit removes parser support for `extern crate "foo" as bar` as the
renamed crate is now required to be an identifier. Additionally this commit
enables hard errors on crate names that contain hyphens in them, they must now
solely contain alphanumeric characters or underscores.
If the crate name is inferred from the file name, however, the file name
`foo-bar.rs` will have the crate name inferred as `foo_bar`. If a binary is
being emitted it will have the name `foo-bar` and a library will have the name
`libfoo_bar.rlib`.
This commit is a breaking change for a number of reasons:
* Old syntax is being removed. This was previously only issuing warnings.
* The output for the compiler when input is received on stdin is now `rust_out`
instead of `rust-out`.
* The crate name for a crate in the file `foo-bar.rs` is now `foo_bar` which can
affect infrastructure such as logging.
[breaking-change]
The compiler will now issue a warning for crates that have syntax of the form
`extern crate "foo" as bar`, but it will still continue to accept this syntax.
Additionally, the string `foo-bar` will match the crate name `foo_bar` to assist
in the transition period as well.
This patch will land hopefully in tandem with a Cargo patch that will start
translating all crate names to have underscores instead of hyphens.
cc #23533
Unstable items used in a macro expansion will now always trigger
stability warnings, *unless* the unstable items are directly inside a
macro marked with `#[allow_internal_unstable]`. IOW, the compiler warns
unless the span of the unstable item is a subspan of the definition of a
macro marked with that attribute.
E.g.
#[allow_internal_unstable]
macro_rules! foo {
($e: expr) => {{
$e;
unstable(); // no warning
only_called_by_foo!();
}}
}
macro_rules! only_called_by_foo {
() => { unstable() } // warning
}
foo!(unstable()) // warning
The unstable inside `foo` is fine, due to the attribute. But the
`unstable` inside `only_called_by_foo` is not, since that macro doesn't
have the attribute, and the `unstable` passed into `foo` is also not
fine since it isn't contained in the macro itself (that is, even though
it is only used directly in the macro).
In the process this makes the stability tracking much more precise,
e.g. previously `println!("{}", unstable())` got no warning, but now it
does. As such, this is a bug fix that may cause [breaking-change]s.
The attribute is definitely feature gated, since it explicitly allows
side-stepping the feature gating system.
This commit deprecates the majority of std::old_io::fs in favor of std::fs and
its new functionality. Some functions remain non-deprecated but are now behind a
feature gate called `old_fs`. These functions will be deprecated once
suitable replacements have been implemented.
The compiler has been migrated to new `std::fs` and `std::path` APIs where
appropriate as part of this change.
This allows to create proper debuginfo line information for items inlined from other crates (e.g. instantiations of generics).
Only the codemap's 'metadata' is stored in a crate's metadata. That is, just filename, line-beginnings, etc. but not the actual source code itself. We are thus missing the opportunity of making Rust the first "open-source-only" programming language out there. Pity.
#[plugin] #[no_link] extern crate bleh;
becomes a crate attribute
#![plugin(bleh)]
The feature gate is still required.
It's almost never correct to link a plugin into the resulting library /
executable, because it will bring all of libsyntax and librustc with it.
However if you really want this behavior, you can get it with a separate
`extern crate` item in addition to the `plugin` attribute.
Fixes#21043.
Fixes#20769.
[breaking-change]
Add special error for this case and help message `please recompile this crate using --crate-type lib`, also list found candidates.
See issue #14416
r? @alexcrichton
Previously if --extern was specified it would not override crates in the
standard distribution, leading to issues like #21771. This commit alters the
behavior such that if --extern is passed then it will always override any other
choice of crates and no previous match will be used (unless it is the same path
as --extern).
Closes#21771
With the addition of separate search paths to the compiler, it was intended that
applications such as Cargo could require a `--extern` flag per `extern crate`
directive in the source. The system can currently be subverted, however, due to
the `existing_match()` logic in the crate loader.
When loading crates we first attempt to match an `extern crate` directive
against all previously loaded crates to avoid reading metadata twice. This "hit
the cache if possible" step was erroneously leaking crates across the search
path boundaries, however. For example:
extern crate b;
extern crate a;
If `b` depends on `a`, then it will load crate `a` when the `extern crate b`
directive is being processed. When the compiler reaches `extern crate a` it will
use the previously loaded version no matter what. If the compiler was not
invoked with `-L crate=path/to/a`, it will still succeed.
This behavior is allowing `extern crate` declarations in Cargo without a
corresponding declaration in the manifest of a dependency, which is considered
a bug.
This commit fixes this problem by keeping track of the origin search path for a
crate. Crates loaded from the dependency search path are not candidates for
crates which are loaded from the crate search path.
As a result of this fix, this is a likely a breaking change for a number of
Cargo packages. If the compiler starts informing that a crate can no longer be
found, it likely means that the dependency was forgotten in your Cargo.toml.
[breaking-change]
This warning has been around in the compiler for quite some time now, but the
real place for a warning like this, if it should exist, is in Cargo, not in the
compiler itself. It's a first-class feature of Cargo that multiple versions of a
crate can be compiled into the same executable, and we shouldn't be warning
about our first-class features.
