bjoernager/rust
bjoernager/rust
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PR fixup

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This commit is contained in:
Aman Arora 2021-09-22 05:17:30 -04:00
parent d2cbe21756
commit 994793faab
19 changed files with 86 additions and 62 deletions
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23
compiler/rustc_ty_utils/src/needs_drop.rs
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@ -240,13 +240,22 @@ fn adt_significant_drop_tys(
def_id: DefId,
) -> Result<&ty::List<Ty<'_>>, AlwaysRequiresDrop> {
let adt_has_dtor = |adt_def: &ty::AdtDef| {
adt_def.destructor(tcx).map(|dtor| {
if tcx.has_attr(dtor.did, sym::rustc_insignificant_dtor) {
DtorType::Insignificant
} else {
DtorType::Significant
}
})
let is_marked_insig = tcx.has_attr(adt_def.did, sym::rustc_insignificant_dtor);
if is_marked_insig {
// In some cases like `std::collections::HashMap` where the struct is a wrapper around
// a type that is a Drop type, and the wrapped type (eg: `hashbrown::HashMap`) lies
// outside stdlib, we might choose to still annotate the the wrapper (std HashMap) with
// `rustc_insignificant_dtor`, even if the type itself doesn't have a `Drop` impl.
Some(DtorType::Insignificant)
} else if adt_def.destructor(tcx).is_some() {
// There is a Drop impl and the type isn't marked insignificant, therefore Drop must be
// significant.
Some(DtorType::Significant)
} else {
// No destructor found nor the type is annotated with `rustc_insignificant_dtor`, we
// treat this as the simple case of Drop impl for type.
None
}
};
adt_drop_tys_helper(tcx, def_id, adt_has_dtor)
}