CFG_RELEASE, CFG_VER_HASH and CFG_VER_DATE were only available as an output
to stdout from the driver::version() function that had an inconvenient
signature.
This makes it easier to experiment with improved quasiquoting as an ordinary
plugin library.
The list of quote macros in feature_gate.rs was already out of sync;
this commit also prevents that problem in the future.
Deprecates the `find_or_*` family of "internal mutation" methods on `HashMap` in
favour of the "external mutation" Entry API as part of RFC 60. Part of #17320,
but this still needs to be done on the rest of the maps. However they don't have
any internal mutation methods defined, so they can be done without deprecating
or breaking anything. Work on `BTree` is part of the complete rewrite in #17334.
The implemented API deviates from the API described in the RFC in two key places:
* `VacantEntry.set` yields a mutable reference to the inserted element to avoid code
duplication where complex logic needs to be done *regardless* of whether the entry
was vacant or not.
* `OccupiedEntry.into_mut` was added so that it is possible to return a reference
into the map beyond the lifetime of the Entry itself, providing functional parity
to `VacantEntry.set`.
This allows the full find_or_insert functionality to be implemented using this API.
A PR will be submitted to the RFC to amend this.
[breaking-change]
Change to resolve and update compiler and libs for uses.
[breaking-change]
Enum variants are now in both the value and type namespaces. This means that
if you have a variant with the same name as a type in scope in a module, you
will get a name clash and thus an error. The solution is to either rename the
type or the variant.
Recursive items are currently detected in the `check_const` pass which runs after type checking. This means a recursive static item used as an array length will cause type checking to blow the stack. This PR separates the recursion check out into a separate pass which is run before type checking.
Closes issue #17252
r? @nick29581
I would like to map this information back to AST nodes, so that we can print remarks with spans, and so that remarks can be enabled on a per-function basis. Unfortunately, doing this would require a lot more code restructuring — for example, we currently throw away the AST map and lots of other information before LLVM optimizations run. So for the time being, we print the remarks with debug location strings from LLVM. There's a warning if you use `-C remark` without `--debuginfo`.
Fixes#17116.
This new pass is run before type checking so that recursive items
are detected beforehand. This prevents going into an infinite
recursion during type checking when a recursive item is used in
an array type.
As a bonus, use `span_err` instead of `span_fatal` so multiple
errors can be reported.
Closes issue #17252
Closes#16813
r? @nikomatsakis I feel like I should be checking more things in check_rvalues, but not sure what - I don't properly understand expr_use_visitor
Refactor the code in `llvm::back` that invokes LLVM optimization and codegen
passes so that it can be called from worker threads. (Previously, it used
`&Session` extensively, and `Session` is not `Share`.) The new code can handle
multiple compilation units, by compiling each unit to `crate.0.o`, `crate.1.o`,
etc., and linking together all the `crate.N.o` files into a single `crate.o`
using `ld -r`. The later linking steps can then be run unchanged.
The new code preserves the behavior of `--emit`/`-o` when building a single
compilation unit. With multiple compilation units, the `--emit=asm/ir/bc`
options produce multiple files, so combinations like `--emit=ir -o foo.ll` will
not actually produce `foo.ll` (they instead produce several `foo.N.ll` files).
The new code supports `-Z lto` only when using a single compilation unit.
Compiling with multiple compilation units and `-Z lto` will produce an error.
(I can't think of any good reason to do such a thing.) Linking with `-Z lto`
against a library that was built as multiple compilation units will also fail,
because the rlib does not contain a `crate.bytecode.deflate` file. This could
be supported in the future by linking together the `crate.N.bc` files produced
when compiling the library into a single `crate.bc`, or by making the LTO code
support multiple `crate.N.bytecode.deflate` files.
Break up `CrateContext` into `SharedCrateContext` and `LocalCrateContext`. The
local piece corresponds to a single compilation unit, and contains all
LLVM-related components. (LLVM data structures are tied to a specific
`LLVMContext`, and we will need separate `LLVMContext`s to safely run
multithreaded optimization.) The shared piece contains data structures that
need to be shared across all compilation units, such as the `ty::ctxt` and some
tables related to crate metadata.
Different Identifiers and Names can have identical textual representations, but different internal representations, due to the macro hygiene machinery (syntax contexts and gensyms). This provides a way to see these internals by compiling with `--pretty expanded,hygiene`.
This is useful for debugging & hacking on macros (e.g. diagnosing https://github.com/rust-lang/rust/issues/15750/https://github.com/rust-lang/rust/issues/15962 likely would've been faster with this functionality).
E.g.
```rust
#![feature(macro_rules)]
// minimal junk
#![no_std]
macro_rules! foo {
($x: ident) => { y + $x }
}
fn bar() {
foo!(x)
}
```
```rust
#![feature(macro_rules)]
// minimal junk
#![no_std]
fn bar /* 61#0 */() { y /* 60#2 */ + x /* 58#3 */ }
```
`--pretty expanded,hygiene` is helpful with debugging macro issues,
since two identifiers/names can be textually the same, but different
internally (resulting in weird "undefined variable" errors).
This adds support for lint groups to the compiler. Lint groups are a way of
grouping a number of lints together under one name. For example, this also
defines a default lint for naming conventions, named `bad_style`. Writing
`#[allow(bad_style)]` is equivalent to writing
`#[allow(non_camel_case_types, non_snake_case, non_uppercase_statics)]`. These
lint groups can also be defined as a compiler plugin using the new
`Registry::register_lint_group` method.
This also adds two built-in lint groups, `bad_style` and `unused`. The contents
of these groups can be seen by running `rustc -W help`.
