diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_ty_utils/src/abi.rs | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/compiler/rustc_ty_utils/src/abi.rs b/compiler/rustc_ty_utils/src/abi.rs index d644cbccea1..73d2d278f93 100644 --- a/compiler/rustc_ty_utils/src/abi.rs +++ b/compiler/rustc_ty_utils/src/abi.rs @@ -273,9 +273,11 @@ fn adjust_for_rust_scalar<'tcx>( | PointerKind::UniqueBorrowed | PointerKind::UniqueBorrowedPinned => false, PointerKind::UniqueOwned => noalias_for_box, - PointerKind::Frozen => !is_return, + PointerKind::Frozen => true, }; - if no_alias { + // We can never add `noalias` in return position; that LLVM attribute has some very surprising semantics + // (see <https://github.com/rust-lang/unsafe-code-guidelines/issues/385#issuecomment-1368055745>). + if no_alias && !is_return { attrs.set(ArgAttribute::NoAlias); } |