Struct ImproperCTypesLint 

pub(crate) struct ImproperCTypesLint {
    known_safe: RefCell<FxHashSet<(Hash128, u8)>>,
}

Remembers types we already checked and found FFI-safe, so we don’t check the same type again every time it shows up in another function. We only remember “safe” types, never “unsafe” ones. That way we never need to keep the actual type around, just a fingerprint of it.

Fields

known_safe: RefCell<FxHashSet<(Hash128, u8)>>

A fingerprint of the type, not the type itself. Uses a big 128-bit fingerprint (not a smaller 64-bit one) so two different types can’t accidentally get treated as the same one.

Implementations

impl<'tcx> ImproperCTypesLint

fn cache_key( cx: &LateContext<'tcx>, ty: Ty<'tcx>, flags: RootUseFlags, ) -> (Hash128, u8)

fn check_ffi_type( &self, cx: &LateContext<'tcx>, ty: Ty<'tcx>, state: VisitorState, span: Span, mode: CItemKind, check: impl FnOnce() -> FfiResult<'tcx>, )

impl ImproperCTypesLint

pub fn lint_vec() -> LintVec

impl<'tcx> ImproperCTypesLint

fn check_type_for_external_abi_fnptr( &mut self, cx: &LateContext<'tcx>, state: VisitorState, hir_ty: &Ty<'tcx>, ty: Ty<'tcx>, fn_mode: CItemKind, )

Find any fn-ptr types with external ABIs in ty, and FFI-checks them. For example, Option<extern "C" fn()> FFI-checks extern "C" fn().

fn check_fn_for_external_abi_fnptr( &mut self, cx: &LateContext<'tcx>, fn_mode: CItemKind, def_id: LocalDefId, decl: &'tcx FnDecl<'_>, )

Regardless of a function’s need to be “ffi-safe”, look for fn-ptr argument/return types that need to be checked for ffi-safety.

fn check_reprc_adt( &mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>, adt_def: AdtDef<'tcx>, )

For a local definition of a #[repr(C)] struct/enum/union, check that it is indeed FFI-safe.

fn check_foreign_static( &mut self, cx: &LateContext<'tcx>, id: OwnerId, span: Span, )

fn check_foreign_fn( &mut self, cx: &LateContext<'tcx>, fn_mode: CItemKind, def_id: LocalDefId, decl: &'tcx FnDecl<'_>, )

Check if a function’s argument types and result type are “ffi-safe”.

fn process_ffi_result( &self, cx: &LateContext<'tcx>, sp: Span, res: FfiResult<'tcx>, fn_mode: CItemKind, )

fn emit_ffi_unsafe_type_lint( &self, cx: &LateContext<'tcx>, ty: Ty<'tcx>, sp: Span, note: DiagMessage, help: Option<DiagMessage>, fn_mode: CItemKind, )

Trait Implementations

impl Default for ImproperCTypesLint

fn default() -> Self

Returns the “default value” for a type.

impl<'tcx> LateLintPass<'tcx> for ImproperCTypesLint

ImproperCTypesDefinitions checks items outside of foreign items (e.g. stuff that isn’t in extern "C" { } blocks):

• extern "<abi>" fn definitions are checked in the same way as the ImproperCtypesDeclarations visitor checks functions if <abi> is external (e.g. “C”).
• All other items which contain types (e.g. other functions, struct definitions, etc) are checked for extern fn-ptrs with external ABIs.

fn check_foreign_item(&mut self, cx: &LateContext<'tcx>, it: &ForeignItem<'tcx>)

fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>)

fn check_field_def( &mut self, cx: &LateContext<'tcx>, field: &'tcx FieldDef<'tcx>, )

fn check_fn( &mut self, cx: &LateContext<'tcx>, kind: FnKind<'tcx>, decl: &'tcx FnDecl<'_>, _: &'tcx Body<'_>, _: Span, id: LocalDefId, )

fn check_body(&mut self, _: &LateContext<'tcx>, _: &Body<'tcx>)

fn check_body_post(&mut self, _: &LateContext<'tcx>, _: &Body<'tcx>)

fn check_crate(&mut self, _: &LateContext<'tcx>)

fn check_crate_post(&mut self, _: &LateContext<'tcx>)

fn check_mod( &mut self, _: &LateContext<'tcx>, _: &'tcx Mod<'tcx>, _: LocalModId, )

fn check_item_post(&mut self, _: &LateContext<'tcx>, _: &'tcx Item<'tcx>)

fn check_local(&mut self, _: &LateContext<'tcx>, _: &'tcx LetStmt<'tcx>)

fn check_block(&mut self, _: &LateContext<'tcx>, _: &'tcx Block<'tcx>)

fn check_block_post(&mut self, _: &LateContext<'tcx>, _: &'tcx Block<'tcx>)

fn check_stmt(&mut self, _: &LateContext<'tcx>, _: &'tcx Stmt<'tcx>)

fn check_arm(&mut self, _: &LateContext<'tcx>, _: &'tcx Arm<'tcx>)

fn check_pat(&mut self, _: &LateContext<'tcx>, _: &'tcx Pat<'tcx>)

fn check_lit(&mut self, _: &LateContext<'tcx>, _: HirId, _: Lit, _: bool)

fn check_expr(&mut self, _: &LateContext<'tcx>, _: &'tcx Expr<'tcx>)

fn check_expr_post(&mut self, _: &LateContext<'tcx>, _: &'tcx Expr<'tcx>)

fn check_ty(&mut self, _: &LateContext<'tcx>, _: &'tcx Ty<'tcx, AmbigArg>)

fn check_generic_param( &mut self, _: &LateContext<'tcx>, _: &'tcx GenericParam<'tcx>, )

fn check_generics(&mut self, _: &LateContext<'tcx>, _: &'tcx Generics<'tcx>)

fn check_poly_trait_ref( &mut self, _: &LateContext<'tcx>, _: &'tcx PolyTraitRef<'tcx>, )

fn check_trait_item(&mut self, _: &LateContext<'tcx>, _: &'tcx TraitItem<'tcx>)

fn check_impl_item(&mut self, _: &LateContext<'tcx>, _: &'tcx ImplItem<'tcx>)

fn check_impl_item_post( &mut self, _: &LateContext<'tcx>, _: &'tcx ImplItem<'tcx>, )

fn check_variant(&mut self, _: &LateContext<'tcx>, _: &'tcx Variant<'tcx>)

fn check_path(&mut self, _: &LateContext<'tcx>, _: &Path<'tcx>, _: HirId)

fn check_attribute(&mut self, _: &LateContext<'tcx>, _: &'tcx Attribute)

fn check_attributes(&mut self, _: &LateContext<'tcx>, _: &'tcx [Attribute])

fn check_attributes_post(&mut self, _: &LateContext<'tcx>, _: &'tcx [Attribute])

impl LintPass for ImproperCTypesLint

fn name(&self) -> &'static str

fn get_lints(&self) -> LintVec

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 40 bytes