Introduce HirId, a replacement for ast::NodeId after lowering to HIR
This is the first step towards implementing #40303. This PR introduces the `HirId` type and generates a `HirId` for everything that would be assigned one (i.e. stuff in the HIR), but the HIR data types still use `NodeId` for now. Changing that is a big refactoring that I want to do in a separate PR.
A `HirId` uniquely identifies a node in the HIR of the current crate. It is composed of the `owner`, which is the `DefIndex` of the directly enclosing `hir::Item`, `hir::TraitItem`, or `hir::ImplItem` (i.e. the closest "item-like"), and the `local_id` which is unique within the given owner.
This PR is also running a number of consistency checks for the generated `HirId`s:
- Does `NodeId` in the HIR have a corresponding `HirId`?
- Is the `owner` part of each `HirId` consistent with its position in the HIR?
- Do the numerical values of the `local_id` part all lie within a dense range of integers?
cc @rust-lang/compiler
r? @eddyb or @nikomatsakis
Teach rustc --emit=mir
I'm opening this PR to discuss:
1. Is this a good idea?
1. Is this a good implementation?
I'm sure people will have opinions on both points!
This spawned from https://github.com/rust-lang/rust/issues/31847#issuecomment-279179057, so I figured a prototype implementation could help provide a seed to talk about.
Nit: LLVM & Clang latest version is 4.0
Small nit: since latest Clang version is 4.0 it's nice to reflect this in the documentation.
Also, I couldn't find anything, but there might be any hard-coded check that Clang version matches "3.X" anywhere in the build system; if there is one, it'd be great to bump that one too.
str: Make docs consistently punctuated
Every so slightly pointless one character PR, but this was driving me nuts while reading the docs a moment ago (all the [other public structs](https://doc.rust-lang.org/std/str/index.html#structs) have descriptions that end in a full-stop).
Make the filenames of .stamp files generated by compiletest shorter
Otherwise we run into filename length limitations on some file systems. See https://bugs.launchpad.net/ecryptfs/+bug/344878 for an example where we only can have ~145 characters for filenames.
r? @alexcrichton
appveyor: Use Ninja to build LLVM on MinGW
I have a suspicion that MinGW's make is the cause of #40546 rather than anything
else, but that's purely a suspicion without any facts to back it up. In any case
we'll eventually be moving the MSVC build over to Ninja in order to leverage
sccache regardless, so this commit simply jumpstarts that process by downloading
Ninja for use by MinGW anyway.
I'm not sure if this closes#40546 for real, but this is my current best shot at
closing it out, so...
Closes#40546
Forbid conflicts between macros 1.0 exports and macros 2.0 exports
This PR forbids for conflicts between `#[macro_export]`/`#[macro_reexport]` macro exports and `pub use` macro exports. For example,
```rust
// crate A:
pub use macros::foo;
//^ This is allowed today, will be forbidden by this PR.
// crate B:
extern crate A; // This triggers a confusing error today.
use A::foo; // This could refer to refer to either macro export in crate A.
```
r? @nrc
This replaces the `std::collections:#️⃣:table::RevMoveBuckets`
iterator with a simpler `while` loop. This iterator was only used for
dropping the remaining elements of a `RawTable`, so instead we can just
loop through directly and drop them in place.
This should be functionally equivalent to the former code, but a little
easier to read. I was hoping it might have some performance benefit
too, but it seems the optimizer was already good enough to see through
the iterator -- the generated code is nearly the same. Maybe it will
still help if an element type has more complicated drop code.
HirId has a more stable representation than NodeId, meaning that
modifications to one item don't influence (part of) the IDs within
other items. The other part is a DefIndex for which there already
is a way of stable hashing and persistence.
This commit introduces the HirId type and generates a HirId for
every NodeId during HIR lowering, but the resulting values are
not yet used anywhere, except in consistency checks.
This reverts commit dc0bb3f283, reversing
changes made to e879aa43ef.
This is a temporary step intended to fix regressions. A more
comprehensive fix for type inference and dead-code is in the works.
It's fairly common to expose an API which takes an `IntoIterator` and
immediately collects that into a vector. It's also common to buffer
a bunch of items into a vector and then pass that into one of these
APIs. If the iterator hasn't been advanced, we can make this `from_iter`
simply reassemble the original `Vec` with no actual iteration or
reallocation.
I have a suspicion that MinGW's make is the cause of #40546 rather than anything
else, but that's purely a suspicion without any facts to back it up. In any case
we'll eventually be moving the MSVC build over to Ninja in order to leverage
sccache regardless, so this commit simply jumpstarts that process by downloading
Ninja for use by MinGW anyway.
I'm not sure if this closes#40546 for real, but this is my current best shot at
closing it out, so...
Closes#40546