typestrong const integers
~~It would be great if someone could run crater on this PR, as this has a high danger of breaking valid code~~ Crater ran. Good to go.
----
So this PR does a few things:
1. ~~const eval array values when const evaluating an array expression~~
2. ~~const eval repeat value when const evaluating a repeat expression~~
3. ~~const eval all struct and tuple fields when evaluating a struct/tuple expression~~
4. remove the `ConstVal::Int` and `ConstVal::Uint` variants and replace them with a single enum (`ConstInt`) which has variants for all integral types
* `usize`/`isize` are also enums with variants for 32 and 64 bit. At creation and various usage steps there are assertions in place checking if the target bitwidth matches with the chosen enum variant
5. enum discriminants (`ty::Disr`) are now `ConstInt`
6. trans has its own `Disr` type now (newtype around `u64`)
This obviously can't be done without breaking changes (the ones that are noticable in stable)
We could probably write lints that find those situations and error on it for a cycle or two. But then again, those situations are rare and really bugs imo anyway:
```rust
let v10 = 10 as i8;
let v4 = 4 as isize;
assert_eq!(v10 << v4 as usize, 160 as i8);
```
stops compiling because 160 is not a valid i8
```rust
struct S<T, S> {
a: T,
b: u8,
c: S
}
let s = S { a: 0xff_ff_ff_ffu32, b: 1, c: 0xaa_aa_aa_aa as i32 };
```
stops compiling because `0xaa_aa_aa_aa` is not a valid i32
----
cc @eddyb @pnkfelix
related: https://github.com/rust-lang/rfcs/issues/1071
std: Fix tracking issues and clean deprecated APIs
This PR fixes up a number of discrepancies found with tracking issues (some closed, some needed new ones, etc), and also cleans out all pre-1.8 deprecated APIs. The big beast here was dealing with `std::dynamic_lib`, and via many applications of a large hammer it's now out of the standard library.
Removes all unstable and deprecated APIs prior to the 1.8 release. All APIs that
are deprecated in the 1.8 release are sticking around for the rest of this
cycle.
Some notable changes are:
* The `dynamic_lib` module was moved into `rustc_back` as the compiler still
relies on a few bits and pieces.
* The `DebugTuple` formatter now special-cases an empty struct name with only
one field to append a trailing comma.
Add a link validator to rustbuild
This commit was originally targeted at just adding a link checking script to the rustbuild system. This ended up snowballing a bit to extend rustbuild to be amenable to various tools we have as part of the build system in general.
There's a new `src/tools` directory which has a number of scripts/programs that are purely intended to be used as part of the build system and CI of this repository. This is currently inhabited by rustbook, the error index generator, and a new linkchecker script added as part of this PR. I suspect that more tools like compiletest, tidy scripts, snapshot scripts, etc will migrate their way into this directory over time.
The commit which adds the error index generator shows the steps necessary to add new tools to the build system, namely:
1. New steps are defined for building the tool and running the tool
2. The dependencies are configured
3. The steps are implemented
In terms of the link checker, these commits do a few things:
* A new `src/tools/linkchecker` script is added. This will read an entire documentation tree looking for broken relative links (HTTP links aren't followed yet).
* A large number of broken links throughout the documentation were fixed. Many of these were just broken when viewed from core as opposed to std, but were easily fixed.
* A few rustdoc bugs here and there were fixed
rustdoc: correct src-link url
It would have been nice for htmldocck to catch this, especially since there are rustdoc tests specifically for checking src-links.
fixes#32113
Distinguish fn item types to allow reification from nothing to fn pointers.
The first commit is a rebase of #26284, except for files that have moved since.
This is a [breaking-change], due to:
* each FFI function has a distinct type, like all other functions currently do
* all generic parameters on functions are recorded in their item types, e.g.:
`size_of::<u8>` & `size_of::<i8>`'s types differ despite their identical signature.
* function items are zero-sized, which will stop transmutes from working on them
The first two cases are handled in most cases with the new coerce-unify logic,
which will combine incompatible function item types into function pointers,
at the outer-most level of if-else chains, match arms and array literals.
The last case is specially handled during type-checking such that transmutes
from a function item type to a pointer or integer type will continue to work for
another release cycle, but are being linted against. To get rid of warnings and
ensure your code will continue to compile, cast to a pointer before transmuting.
There's a lot of stuff wrong with the representation of these types:
TyFnDef doesn't actually uniquely identify a function, TyFnPtr is used to
represent method calls, TyFnDef in the sub-expression of a cast isn't
correctly reified, and probably some other stuff I haven't discovered yet.
Splitting them seems like the right first step, though.
Right now whenever rustdoc inlines a struct or enum from another crate it ends
up inlining *all* `impl` items found in the other crate at the same time. The
rationale for this was to discover all trait impls which are otherwise not
probed for. This unfortunately picks up a lot of impls of public traits for
private types, causing lots of broken links.
This commit instead hoards all of those inlined impls into a temporary storage
location which is then selectively drawn from whenever we inline a new type.
This should ensure that we still inline all relevant impls while avoiding all
private ones.
This is mostly cleanup of individual code bits and code reuse for `clean::Attribute` handling.
The only change in behaviour should be that emitted sources are now being recorded and queried when trying to create src-links to local source-files.
r? @alexcrichton
- Empty `.sidebar .location` caused "grey line" on top of the documentation page (under 700px) fixed.
- `.sidebar .location` appearance improvement in responsive mode.
For summary descriptions we need the first paragraph (adjacent lines
until a blank line) - but the rendered markdown of a code block did not
leave a blank line in the html and was thus included in the summary line.
