Currently, we serialize the same crate metadata for proc-macro crates as
we do for normal crates. This is quite wasteful - almost none of this
metadata is ever used, and much of it can't even be deserialized (if it
contains a foreign `CrateNum`).
This PR changes metadata encoding to skip encoding the majority of crate
metadata for proc-macro crates. Most of the `Lazy<[T]>` fields are left
completetly empty, while the non-lazy fields are left as-is.
Additionally, proc-macros now have a def span that does not include
their body. This was done for normal functions in #75465, but was missed
for proc-macros.
As a result of this PR, we should only ever encode local `CrateNum`s
when encoding proc-macro crates. I've added a specialized serialization
impl for `CrateNum` to assert this.
Remove TrustedLen requirement from BuilderMethods::switch
The main use case of TrustedLen is allowing APIs to specialize on it,
but no use of it uses that specialization. Instead, only the .len()
function provided by ExactSizeIterator is used, which is already
required to be accurate.
Thus, the TrustedLen requirement on BuilderMethods::switch is redundant.
Add `#![feature(const_fn_floating_point_arithmetic)]`
cc #76618
This is a template for splitting up `const_fn` into granular feature gates. I think this will make it easier, both for us and for users, to track stabilization of each individual feature. We don't *have* to do this, however. We could also keep stabilizing things out from under `const_fn`.
cc @rust-lang/wg-const-eval
r? @oli-obk
Add `x.py setup`
Closes#76503.
- Suggest `x.py setup` if config.toml doesn't exist yet
- Prompt for a profile if not given on the command line
- Print the configuration that will be used
- Print helpful starting commands after setup
- Link to the dev-guide after finishing
Explicitly document the size guarantees that Option makes.
Triggered by a discussion on wg-unsafe-code-guidelines about which layouts of `Option<T>` one can guarantee are optimised to a single pointer.
CC @RalfJung
Std/thread: deny unsafe op in unsafe fn
Partial fix of #73904.
This encloses `unsafe` operations in `unsafe fn` in `libstd/thread`.
`@rustbot` modify labels: F-unsafe-block-in-unsafe-fn
Move from {{closure}}#0 syntax to {closure#0} for (def) path components
Part of #70334
I followed the approach described by `@eddyb` and introduced a `DefPathDataName` enum.
To preserve compatibility, in various places, I had to rely on formatting manually by calling `format!("{{{{{}}}}}", namespace)`.
My questions are:
* Do we want to convert for places to use the new naming scheme? Or shall I re-add `DefPathData::as_symbol` but renamed as `DefPathData::as_legacy_symbol` to avoid manually allocating the legacy symbols?
* Do we want to `impl Display for DisambiguatedDefPathData` to avoid manually calling `write!(s, "{{{}#{}}}", namespace, component.disambiguator)`?
* We might also want to improve naming for `DefPathDataName` and `DefPathData::get_name`
r? `@eddyb`