Rollup merge of #116829 - fmease:rust-aint-c, r=compiler-errors

Make `#[repr(Rust)]` incompatible with other (non-modifier) representation hints like `C` and `simd`

Read more about this change here: https://github.com/rust-lang/rust/pull/116829#issuecomment-1768618240.

Fixes [after backport] #116825.
This commit is contained in:
León Orell Valerian Liehr
2023-10-19 04:34:46 +02:00
committed by GitHub
4 changed files with 80 additions and 4 deletions

View File

@@ -1776,6 +1776,7 @@ impl CheckAttrVisitor<'_> {
.collect();
let mut int_reprs = 0;
let mut is_explicit_rust = false;
let mut is_c = false;
let mut is_simd = false;
let mut is_transparent = false;
@@ -1787,7 +1788,9 @@ impl CheckAttrVisitor<'_> {
}
match hint.name_or_empty() {
sym::Rust => {}
sym::Rust => {
is_explicit_rust = true;
}
sym::C => {
is_c = true;
match target {
@@ -1897,12 +1900,16 @@ impl CheckAttrVisitor<'_> {
// Error on repr(transparent, <anything else>).
if is_transparent && hints.len() > 1 {
let hint_spans: Vec<_> = hint_spans.clone().collect();
let hint_spans = hint_spans.clone().collect();
self.tcx.sess.emit_err(errors::TransparentIncompatible {
hint_spans,
target: target.to_string(),
});
}
if is_explicit_rust && (int_reprs > 0 || is_c || is_simd) {
let hint_spans = hint_spans.clone().collect();
self.tcx.sess.emit_err(errors::ReprConflicting { hint_spans });
}
// Warn on repr(u8, u16), repr(C, simd), and c-like-enum-repr(C, u8)
if (int_reprs > 1)
|| (is_simd && is_c)
@@ -1919,7 +1926,7 @@ impl CheckAttrVisitor<'_> {
CONFLICTING_REPR_HINTS,
hir_id,
hint_spans.collect::<Vec<Span>>(),
errors::ReprConflicting,
errors::ReprConflictingLint,
);
}
}