Filter global bounds from ParamEnv again.
This PR adds back the filtering of global bounds from ParamEnv as a temporary solution for #50825.
<details>
Long term, the fix seems like it should be changing the priority in `candidate_should_be_dropped_in_favor_of` so that (global) where clauses aren't considered as highly.
a722296b6e/src/librustc/traits/select.rs (L2017-L2022)
</details>
r? @nikomatsakis
rustc: Fix joint-ness of stringified token-streams
This commit fixes `StringReader`'s parsing of tokens which have been stringified
through procedural macros. Whether or not a token tree is joint is defined by
span information, but when working with procedural macros these spans are often
dummy and/or overridden which means that they end up considering all operators
joint if they can!
The fix here is to track the raw source span as opposed to the overridden span.
With this information we can more accurately classify `Punct` structs as either
joint or not.
Closes#50700
Escape combining characters in char::Debug
Although combining characters are technically printable, they make little sense to print on their own with `Debug`: it'd be better to escape them like non-printable characters.
This is a breaking change, but I imagine the fact `escape_debug` is rare and almost certainly primarily used for debugging that this is an acceptable change.
Resolves#41922.
r? @alexcrichton
cc @clarcharr
Fix issue #50811 (`NaN > NaN` was true).
Fix#50811
Make sure the float comparison output is consistent with the expected behavior when NaN is involved.
----
Note: This PR is a **BREAKING CHANGE**. If you have used `>` or `>=` to compare floats, and make the result as the length of a fixed array type, like:
```rust
use std::f64::NAN;
let x: [u8; (NAN > NAN) as usize] = [1];
```
then the code will no longer compile. Previously, all float comparison involving NaN will just return "Greater", i.e. `NAN > NAN` would wrongly return `true` during const evaluation. If you need to retain the old behavior (why), you may replace `a > b` with `a != a || b != b || a > b`.
stabilize opt-level={s,z}
closes#35784closes#47651
### Rationale
Since the lastest LLVM upgrade rustc / LLVM does more agressive loop unrolling. This results in increased binary size of embedded / no_std programs: a hundreds of bytes increase, or about a 7x increase, in the case of the smallest Cortex-M binary cf. #49260.
As we are shooting for embedded Rust on stable it would be great to also provide a way to optimize for size (which is pretty important for embedded applications that target resource constrained devices) on stable.
Also this has been baking in nightly for a long time.
r? @alexcrichton which team has to sign off this?
Switch Vec from doubling size on growth to using RawVec's reserve
On growth, Vec does not require to exactly double its size for correctness,
like, for example, VecDeque does.
Using reserve instead better expresses this intent. It also allows to reuse
Excess capacity on growth and for better growth-policies to be provided by
RawVec.
r? @sfackler
lexer: Fix span override for the first token in a string
Previously due to peculiarities of `StringReader` construction something like `"a b c d".parse::<TokenStream>()` gave you one non-overridden span for `a` and then three correctly overridden spans for `b`, `c` and `d`.
Now all the spans are overridden.
rustc: introduce {ast,hir}::AnonConst to consolidate so-called "embedded constants".
Previously, constants in array lengths and enum variant discriminants were "merely an expression", and had no separate ID for, e.g. type-checking or const-eval, instead reusing the expression's.
That complicated code working with bodies, because such constants were the only special case where the "owner" of the body wasn't the HIR parent, but rather the same node as the body itself.
Also, if the body happened to be a closure, we had no way to allocate a `DefId` for both the constant *and* the closure, leading to *several* bugs (mostly ICEs where type errors were expected).
This PR rectifies the situation by adding another (`{ast,hir}::AnonConst`) node around every such constant. Also, const generics are expected to rely on the new `AnonConst` nodes, as well (cc @varkor).
* fixes#48838
* fixes#50600
* fixes#50688
* fixes#50689
* obsoletes #50623
r? @nikomatsakis
Speed up the macro parser
These three commits reduce the number of allocations done by the macro parser, in some cases dramatically. For example, for a clean check builds of html5ever, the number of allocations is reduced by 40%.
Here are the rustc-benchmarks that are sped up by at least 1%.
```
html5ever-check
avg: -6.6% min: -10.3% max: -4.1%
html5ever
avg: -5.2% min: -9.5% max: -2.8%
html5ever-opt
avg: -4.3% min: -9.3% max: -1.6%
crates.io-check
avg: -1.8% min: -2.9% max: -0.6%
crates.io-opt
avg: -1.0% min: -2.2% max: -0.1%
crates.io
avg: -1.1% min: -2.2% max: -0.2%
```
rustc: Disallow modules and macros in expansions
This commit feature gates generating modules and macro definitions in procedural
macro expansions. Custom derive is exempt from this check as it would be a large
retroactive breaking change (#50587). It's hoped that we can hopefully stem the
bleeding to figure out a better solution here before opening up the floodgates.
The restriction here is specifically targeted at surprising hygiene results [1]
that result in non-"copy/paste" behavior. Hygiene and procedural macros is
intended to be avoided as much as possible for Macros 1.2 by saying everything
is "as if you copy/pasted the code", but modules and macros are sort of weird
exceptions to this rule that aren't fully fleshed out.
[1]: https://github.com/rust-lang/rust/issues/50504#issuecomment-387734625
cc #50504
Add target for Big-endian ARM Cortex-R4F/R5F MCUs
The ARM Real-Time (‘R’) profile provides high-performing processors for safety-critical environments.
Cortex-R has ARM, Thumb instruction whereas Cortex-M makes use of Thumb only.
CI/Dockerfile is intentionally in the `disabled` folder.
