bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Handle UnsafePointer coercions in one place

Browse source
This commit is contained in:
Oli Scherer 2025-04-09 09:49:24 +00:00
parent c6c179662d
commit f20efc4c61
1 changed files with 22 additions and 36 deletions
Download patch file Download diff file Expand all files Collapse all files

58
compiler/rustc_hir_typeck/src/coercion.rs
View file

@ -247,7 +247,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
ty::FnPtr(a_sig_tys, a_hdr) => {
// We permit coercion of fn pointers to drop the
// unsafe qualifier.
self.coerce_from_fn_pointer(a, a_sig_tys.with(a_hdr), b)
self.coerce_from_fn_pointer(a_sig_tys.with(a_hdr), b)
}
ty::Closure(closure_def_id_a, args_a) => {
// Non-capturing closures are coercible to
@ -813,18 +813,12 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
})
}
fn coerce_from_safe_fn<F, G>(
fn coerce_from_safe_fn(
&self,
a: Ty<'tcx>,
fn_ty_a: ty::PolyFnSig<'tcx>,
b: Ty<'tcx>,
to_unsafe: F,
normal: G,
) -> CoerceResult<'tcx>
where
F: FnOnce(Ty<'tcx>) -> Vec<Adjustment<'tcx>>,
G: FnOnce(Ty<'tcx>) -> Vec<Adjustment<'tcx>>,
{
adjustment: Option<Adjust>,
) -> CoerceResult<'tcx> {
self.commit_if_ok(|snapshot| {
let outer_universe = self.infcx.universe();
@ -833,9 +827,22 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
&& hdr_b.safety.is_unsafe()
{
let unsafe_a = self.tcx.safe_to_unsafe_fn_ty(fn_ty_a);
self.unify_and(unsafe_a, b, to_unsafe)
self.unify_and(unsafe_a, b, |target| match adjustment {
Some(kind) => vec![
Adjustment { kind, target: Ty::new_fn_ptr(self.tcx, fn_ty_a) },
Adjustment {
kind: Adjust::Pointer(PointerCoercion::UnsafeFnPointer),
target,
},
],
None => simple(Adjust::Pointer(PointerCoercion::UnsafeFnPointer))(target),
})
} else {
self.unify_and(a, b, normal)
let a = Ty::new_fn_ptr(self.tcx, fn_ty_a);
self.unify_and(a, b, |target| match adjustment {
None => vec![],
Some(kind) => vec![Adjustment { kind, target }],
})
};
// FIXME(#73154): This is a hack. Currently LUB can generate
@ -852,7 +859,6 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
fn coerce_from_fn_pointer(
&self,
a: Ty<'tcx>,
fn_ty_a: ty::PolyFnSig<'tcx>,
b: Ty<'tcx>,
) -> CoerceResult<'tcx> {
@ -861,15 +867,9 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
//!
let b = self.shallow_resolve(b);
debug!("coerce_from_fn_pointer(a={:?}, b={:?})", a, b);
debug!(?fn_ty_a, ?b, "coerce_from_fn_pointer");
self.coerce_from_safe_fn(
a,
fn_ty_a,
b,
simple(Adjust::Pointer(PointerCoercion::UnsafeFnPointer)),
identity,
)
self.coerce_from_safe_fn(fn_ty_a, b, None)
}
fn coerce_from_fn_item(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> CoerceResult<'tcx> {
@ -916,24 +916,10 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
self.at(&self.cause, self.param_env).normalize(a_sig);
obligations.extend(o1);
let a_fn_pointer = Ty::new_fn_ptr(self.tcx, a_sig);
let InferOk { value, obligations: o2 } = self.coerce_from_safe_fn(
a_fn_pointer,
a_sig,
b,
|unsafe_ty| {
vec![
Adjustment {
kind: Adjust::Pointer(PointerCoercion::ReifyFnPointer),
target: a_fn_pointer,
},
Adjustment {
kind: Adjust::Pointer(PointerCoercion::UnsafeFnPointer),
target: unsafe_ty,
},
]
},
simple(Adjust::Pointer(PointerCoercion::ReifyFnPointer)),
Some(Adjust::Pointer(PointerCoercion::ReifyFnPointer)),
)?;
obligations.extend(o2);