This commit is an implementation of adding custom sections to wasm artifacts in
rustc. The intention here is to expose the ability of the wasm binary format to
contain custom sections with arbitrary user-defined data. Currently neither our
version of LLVM nor LLD supports this so the implementation is currently custom
to rustc itself.
The implementation here is to attach a `#[wasm_custom_section = "foo"]`
attribute to any `const` which has a type like `[u8; N]`. Other types of
constants aren't supported yet but may be added one day! This should hopefully
be enough to get off the ground with *some* custom section support.
The current semantics are that any constant tagged with `#[wasm_custom_section]`
section will be *appended* to the corresponding section in the final output wasm
artifact (and this affects dependencies linked in as well, not just the final
crate). This means that whatever is interpreting the contents must be able to
interpret binary-concatenated sections (or each constant needs to be in its own
custom section).
To test this change the existing `run-make` test suite was moved to a
`run-make-fulldeps` folder and a new `run-make` test suite was added which
applies to all targets by default. This test suite currently only has one test
which only runs for the wasm target (using a node.js script to use `WebAssembly`
in JS to parse the wasm output).
Suggest removing `&`s
This implements the error message discussed in #47744.
We check whether removing each `&` yields a type that satisfies the requested obligation.
Also, it was created a new `NodeId` field in `ObligationCause` in order to iterate through the `&`s. The way it's implemented now, it iterates through the obligation snippet and counts the number of `&`.
r? @estebank
check stability of macro invocations
I haven't implemented tests yet but this should be a pretty solid prototype. I think as-implemented it will also stability-check macro invocations in the same crate, dunno if we want that or not.
I don't know if we want this to go through `rustc::middle::stability` or not, considering the information there wouldn't be available at the time of macro expansion (even for external crates, right?).
r? @nrc
closes#34079
cc @petrochenkov @durka @jseyfried #38356
Fix ICE on malformed plugin attributes
See #48941 for some discussion.
This bug had several duplicate reports which were never closed as dupes:
Fixes#47612Fixes#48387Fixes#48941Fixes#48982
They are disallowed because they have different precedence than
expressions. I assume parenthesis in pattern will be soon stabilized and
thus write that as suggestion directly.
Stabilise feature(never_type). Introduce feature(exhaustive_patterns)
This stabilizes `!`, removing the feature gate as well as the old defaulting-to-`()` behavior. The pattern exhaustiveness checks which were covered by `feature(never_type)` have been moved behind a new `feature(exhaustive_patterns)` gate.
