Use the trait-environment+type as the key. Note that these
are only invoked on types that live for the entire compilation
(no inference artifacts). We no longer need the various special-case
bits and caches that were in place before.
rustc: Add a new `-Z force-unstable-if-unmarked` flag
This commit adds a new `-Z` flag to the compiler for use when bootstrapping the
compiler itself. We want to be able to use crates.io crates, but we also want
the usage of such crates to be as ergonomic as possible! To that end compiler
crates are a little tricky in that the crates.io crates are not annotated as
unstable, nor do they expect to pull in unstable dependencies.
To cover all these situations it's intended that the compiler will forever now
bootstrap with `-Z force-unstable-if-unmarked`. This flags serves a dual purpose
of forcing crates.io crates to themselves be unstable while also allowing them
to use other "unstable" crates.io crates. This should mean that adding a
dependency to compiler no longer requires upstream modification with
unstable/staged_api attributes for inclusion!
Operand: 72 -> 24 B
Statement: 192 -> 96 B
Terminator: 256 -> 112 B
librustc translation memory usage: 1795 -> 1669 MB
next step would be interning lvalues, I suppose?
refactor NonZero, Shared, and Unique APIs
Major difference is that I removed Deref impls, as apparently LLVM has
trouble maintaining metadata with a `&ptr -> &ptr` API. This was cited
as a blocker for ever stabilizing this API. It wasn't that ergonomic
anyway.
* Added `get` to NonZero to replace Deref impl
* Added `ptr` getter to Shared/Unique to replace Deref impl
* Added Unique's `get` and `get_mut` conveniences to Shared
* Deprecated `as_mut_ptr` on Shared in favour of `ptr`
Note that Shared used to primarily expose only `*const` but there isn't
a good justification for that, so I made it `*mut`.
Consider changing to & for let bindings #40402
This is a fix for #40402
For the example
```
fn main() {
let v = vec![String::from("oh no")];
let e = v[0];
}
```
It gives
```
error[E0507]: cannot move out of indexed content
--> ex1.rs:4:13
|
4 | let e = v[0];
| ^^^^ cannot move out of indexed content
|
= help: consider changing to `&v[0]`
error: aborting due to previous error
```
Another alternative is
```
error[E0507]: cannot move out of indexed content
--> ex1.rs:4:13
|
4 | let e = v[0];
| ^^^^ consider changing to `&v[0]`
error: aborting due to previous error
```
Also refer to #41564 for more details.
r? @nikomatsakis
Overall goal: reduce the amount of context a mir pass needs so that it
resembles a query.
- The hooks are no longer "threaded down" to the pass, but rather run
automatically from the top-level (we also thread down the current pass
number, so that the files are sorted better).
- The hook now receives a *single* callback, rather than a callback per-MIR.
- The traits are no longer lifetime parameters, which moved to the
methods -- given that we required
`for<'tcx>` objecs, there wasn't much point to that.
- Several passes now store a `String` instead of a `&'l str` (again, no
point).
Instead of requesting the region maps for the entire crate, request for
a given item etc. Several bits of code were modified to take
`&RegionMaps` as input (e.g., the `resolve_regions_and_report_errors()`
function). I am not totally happy with this setup -- I *think* I'd
rather have the region maps be part of typeck tables -- but at least the
`RegionMaps` works in a "parallel" way to `FreeRegionMap`, so it's not
too bad. Given that I expect a lot of this code to go away with NLL, I
didn't want to invest *too* much energy tweaking it.
remove unnecessary tasks
Remove various unnecessary tasks. All of these are "always execute" tasks that don't do any writes to tracked state (or else an assert would trigger, anyhow). In some cases, they issue lints or errors, but we''ll deal with that -- and anyway side-effects outside of a task don't cause problems for anything that I can see.
The one non-trivial refactoring here is the borrowck conversion, which adds the requirement to go from a `DefId` to a `BodyId`. I tried to make a useful helper here.
r? @eddyb
cc #40746
cc @cramertj @michaelwoerister
borrowck::mir::dataflow: ignore unwind edges of empty drops
This avoids creating drop flags in many unnecessary situations.
Fixes#41110.
r? @nagisa
beta-nominating because regression. However, that is merely a small perf regression and codegen changes are always risky, so we might let this slide for 1.17.
borrowck: consolidate `mut` suggestions
This converts all of borrowck's `mut` suggestions to a new
`mc::ImmutabilityBlame` API instead of the current mix of various hacks.
Fixes#35937.
Fixes#40823.
Fixes#40859.
cc @estebank
r? @pnkfelix
