rustc_codegen_ssa: don't treat inlined variables as debuginfo arguments.
Fixes#67586 by limiting `ArgumentVariable` special-casing to `VarDebugInfo` entries that are in `OUTERMOST_SOURCE_SCOPE`, i.e. the function's own argument scope.
That excludes `VarDebugInfo` from inlined callees, which can also point to the caller's argument locals.
This is a snippet from the optimized MIR (including inlining) of the testcase:
```rust
fn foo(_1: usize) -> usize {
debug bar => _1; // in scope 0 at ./example.rs:2:12: 2:15
let mut _0: usize; // return place in scope 0 at ./example.rs:2:27: 2:32
scope 1 {
debug x => _1; // in scope 1 at /rustc/9ed29b6ff6aa2e048b09c27af8f62ee3040bdb37/src/libcore/convert/mod.rs:106:26: 106:27
}
```
`scope 1` is from inlining the `identity` call, and `debug x => _1;` comes from the body of `core::convert::identity`, so they are now ignored for the purposes of determining the `ArgumentVariable` debuginfo associated to `_1`.
rustc_target: treat enum variants like union members, in call ABIs.
Fixes#68190, by handling non-C-like `enum`s as-if they were an `union` of `struct`s, in call ABIs.
Tests were provided by @sw17ch, from theirs and @bitwalker's original examples.
cc @nagisa @rkruppe
One calls into C functions passing non-c-like enumerations by
value. The other calls into C expecting non-C-like enumerations as
returns.
These test cases are based on the tests provided by @bitwalker on
issue #68190. The original tests were provided at:
2688d5c672
Remove some unsound specializations
This removes the unsound and exploitable specializations in the standard library
* The `PartialEq` and `Hash` implementations for `RangeInclusive` are changed to avoid specialization.
* The `PartialOrd` specialization for slices now specializes on a limited set of concrete types.
* Added some tests for the soundness problems.
replace the leak check with universes, take 2
This PR is an attempt to revive the "universe-based region check", which is an important step towards lazy normalization. Unlike before, we also modify the definition of `'empty` so that it is indexed by a universe. This sidesteps some of the surprising effects we saw before -- at the core, we no longer think that `exists<'a> { forall<'b> { 'b: 'a } }` is solveable. The new region lattice looks like this:
```
static ----------+-----...------+ (greatest)
| | |
early-bound and | |
free regions | |
| | |
scope regions | |
| | |
empty(root) placeholder(U1) |
| / |
| / placeholder(Un)
empty(U1) -- /
| /
... /
| /
empty(Un) -------- (smallest)
```
This PR has three effects:
* It changes a fair number of error messages, I think for the better.
* It fixes a number of bugs. The old algorithm was too conservative and caused us to reject legal subtypings.
* It also causes two regressions (things that used to compile, but now do not).
* `coherence-subtyping.rs` gets an additional error. This is expected.
* `issue-57639.rs` regresses as before, for the reasons covered in #57639.
Both of the regressions stem from the same underlying property: without the leak check, the instantaneous "subtype" check is not able to tell whether higher-ranked subtyping will succeed or not. In both cases, we might be able to fix the problem by doing a 'leak-check like change' at some later point (e.g., as part of coherence).
This is a draft PR because:
* I didn't finish ripping out the leak-check completely.
* We might want to consider a crater run before landing this.
* We might want some kind of design meeting to cover the overall strategy.
* I just remembered I never finished 100% integrating this into the canonicalization code.
* I should also review what happens in NLL region checking -- it probably still has a notion of bottom (empty set).
r? @matthewjasper
Add GitHub issue templates
This PR adds GitHub's issue templates to the repository. Adding templates for two of the most common issues we create on the repository. We could add more specific templates (e.g. ICEs) depending on the response to initial templates. I've included a screenshot of what it looks like, and people can also try out the UI and specific templates, by going to [`XAMPPRocky/rust`](https://github.com/XAMPPRocky/rust/issues/new/choose).
<img width="1115" alt="Screenshot 2020-01-21 at 13 57 46" src="https://user-images.githubusercontent.com/4464295/72807027-c51baa00-3c56-11ea-8a4c-98238489b345.png">
Selectively disable sanitizer instrumentation
Add `no_sanitize` attribute that allows to opt out from sanitizer
instrumentation in an annotated function.
BtreeMap range_search spruced up
#39457 created a lower level entry point for `range_search` to operate on, but it's really not hard to move it up a level of abstraction, making it somewhat shorter and reusing existing unsafe code (`new_edge` is unsafe although it is currently not tagged as such).
Benchmark added. Comparison says there's no real difference:
```
>cargo benchcmp old3.txt new3.txt --threshold 5
name old3.txt ns/iter new3.txt ns/iter diff ns/iter diff % speedup
btree::map::find_seq_100 19 21 2 10.53% x 0.90
btree::map::range_excluded_unbounded 3,117 2,838 -279 -8.95% x 1.10
btree::map::range_included_unbounded 1,768 1,871 103 5.83% x 0.94
btree::set::intersection_10k_neg_vs_10k_pos 35 37 2 5.71% x 0.95
btree::set::intersection_staggered_100_vs_10k 2,488 2,314 -174 -6.99% x 1.08
btree::set::is_subset_10k_vs_100 3 2 -1 -33.33% x 1.50
```
r? @Mark-Simulacrum
It's tautological, and Rust-specific Jargon.
This changes various Option/Result methods to consistently describe unwrapping
behavior using the words "return", "contain", "consume".
It also renames the closure argument of `Return::unwrap_or_else` to `default` to
be consistent with `Option`.
error code examples: replace some more ignore with compile_fail
Now that #68664 has been merged and `compile_fail` attempts a full build rather than `--emit=metadata`, these errors should be caught by `compile_fail` and do not need to be ignored.
Mark fn map_or() as eagerly evaluated.
In the docs for option.rs and result.rs, it is noted for all *_or()
functions that they are eagerly evaluated, except for the map_or()
function.
This commit adds this missing documentation to the two files.
Closes#68866