Expand documentation for `FpCategory`.
I intend these changes to be helpful to readers who are not yet familiar with the quirks of floating-point numbers. Additionally, I felt it was misleading to describe `Nan` as being the result of division by zero, since most divisions by zero (except for 0/0) produce `Infinite` floats, so I moved that remark to the `Infinite` variant with adjustment.
The first sentence of the `Nan` documentation is copied from `f32`; I followed the example of the `f64` documentation by referring to `f32` for general concepts, rather than duplicating the text.
----
I considered making similar changes to the documentation of the `is_*` methods of floats, but decided that that was a much larger and trickier problem; here, each of the variants' descriptions can be expected to be read in context of being mutually exclusive with the others.
Switch to our own mirror of libisl plus `ct-ng oldconfig` fixes
Switching to mirror the ISL libs (#89594) unearthed a (possibly long-standing?) issue with `ct-ng oldconfig`. It always overwrites the mirror config values. This PR adds the ISL mirror, gets rid of `ct-ng oldconfig` and adds crosstools-ng config files which can be used directly. (Edited)
Fixes#89593.
r? `@pietroalbini`
Useless exponent
Closes#7745
I'm open to some thoughts on dropping the exponents on suggestions when it's zero. I personally don't see any problem on this.
changelog: [`useless_exponent`] suggestion drops exponent when exponent value is zero
Move module declarations back into lib.rs
With #7673 we moved a lot of things from lib.rs to lib.foo.rs. Unfortunately, rustfmt doesn't seem to work when module declarations are included via `include!` (and trying the `mod foo; use foo::*;` trick doesn't seem to work much either in our specific case).
With this PR we continue generating everything in subfiles except for module declarations, which are now generated within lib.rs.
changelog: none
Consider unfulfilled obligations in binop errors
When encountering a binop where the types would have been accepted, if
all the predicates had been fulfilled, include information about the
predicates and suggest appropriate `#[derive]`s if possible.
Fix#84515.
When encountering a binop where the types would have been accepted, if
all the predicates had been fulfilled, include information about the
predicates and suggest appropriate `#[derive]`s if possible.
Point at trait(s) that needs to be `impl`emented.
Rollup of 10 pull requests
Successful merges:
- #88706 (Normalize associated type projections when checking return type of main)
- #88828 (Use `libc::sigaction()` instead of `sys::signal()` to prevent a deadlock)
- #88871 (Fix suggestion for nested struct patterns)
- #89317 (Move generic error message to separate branches)
- #89351 (for signed wrapping remainder, do not compare lhs with MIN)
- #89442 (Add check for duplicated doc aliases)
- #89502 (Fix Lower/UpperExp formatting for integers and precision zero)
- #89523 (Make `proc_macro_derive_resolution_fallback` a future-breakage lint)
- #89532 (Document behavior of `MaybeLiveLocals` regarding enums and field-senstivity)
- #89546 (Make an initial guess for metadata size to reduce buffer resizes)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Make an initial guess for metadata size to reduce buffer resizes
When reading metadata, the compiler starts with a `Vec::new()`, which will need to grow repeatedly as the metadata gets decompressed into it. Reduce the number of resizes by starting out at the size of the compressed data.
Document behavior of `MaybeLiveLocals` regarding enums and field-senstivity
This arose from a [discussion on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/189540-t-compiler.2Fwg-mir-opt/topic/MaybeLiveLocals.20and.20Discriminants) where a new contributor attempted to implement a dead-store elimination pass using this analysis. They ran into a nasty hack around `SetDiscriminant` the effect of which is to lets handle assignments of literals to enum-typed locals (e.g. `x = Some(4)`) correctly. This took me a while to figure out.
Document this oddity, so the next person will have an easier time, and add a test to enshrine the current behavior.
r? ``@tmiasko``
Make `proc_macro_derive_resolution_fallback` a future-breakage lint
When `cargo report future-incompatibilities` is stabilized
(see #71249), this will cause dependencies that trigger
this lint to be included in the report.
Fix Lower/UpperExp formatting for integers and precision zero
Fixes the integer part of #89493 (I daren't touch the floating-point formatting code). The issue is that the "subtracted" precision essentially behaves like extra trailing zeros, but this is not currently reflected in the code properly.
for signed wrapping remainder, do not compare lhs with MIN
Since the wrapped remainder is going to be 0 for all cases when the rhs is -1, there is no need to compare the lhs with MIN.
Move generic error message to separate branches
This decomposes an error message in generic constants into more specific branches, for better
readability.
r? ``@lcnr``
