bjoernager/rust
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Make UnsafetyChecker visitor iterate instead of recurse

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This commit is contained in:
Santiago Pastorino 2019-06-05 21:01:17 +02:00
parent 47f4975cd7
commit 2bdaccbbcf
1 changed files with 39 additions and 40 deletions
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79
src/librustc_mir/transform/check_unsafety.rs
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@ -199,11 +199,39 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
fn visit_place(&mut self,
place: &Place<'tcx>,
context: PlaceContext,
location: Location) {
match place {
&Place::Projection(box Projection {
ref base, ref elem
}) => {
_location: Location) {
place.iterate(|place_base, place_projections| {
match place_base {
PlaceBase::Local(..) => {
// Locals are safe.
}
PlaceBase::Static(box Static { kind: StaticKind::Promoted(_), .. }) => {
bug!("unsafety checking should happen before promotion")
}
PlaceBase::Static(box Static { kind: StaticKind::Static(def_id), .. }) => {
if self.tcx.is_mutable_static(*def_id) {
self.require_unsafe("use of mutable static",
"mutable statics can be mutated by multiple threads: aliasing \
violations or data races will cause undefined behavior",
UnsafetyViolationKind::General);
} else if self.tcx.is_foreign_item(*def_id) {
let source_info = self.source_info;
let lint_root =
self.source_scope_local_data[source_info.scope].lint_root;
self.register_violations(&[UnsafetyViolation {
source_info,
description: InternedString::intern("use of extern static"),
details: InternedString::intern(
"extern statics are not controlled by the Rust type system: \
invalid data, aliasing violations or data races will cause \
undefined behavior"),
kind: UnsafetyViolationKind::ExternStatic(lint_root)
}], &[]);
}
}
}
for proj in place_projections {
if context.is_borrow() {
if util::is_disaligned(self.tcx, self.mir, self.param_env, place) {
let source_info = self.source_info;
@ -220,7 +248,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
}], &[]);
}
}
let is_borrow_of_interior_mut = context.is_borrow() && !base
let is_borrow_of_interior_mut = context.is_borrow() && !proj.base
.ty(self.mir, self.tcx)
.ty
.is_freeze(self.tcx, self.param_env, self.source_info.span);
@ -236,7 +264,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
);
}
let old_source_info = self.source_info;
if let &Place::Base(PlaceBase::Local(local)) = base {
if let Place::Base(PlaceBase::Local(local)) = proj.base {
if self.mir.local_decls[local].internal {
// Internal locals are used in the `move_val_init` desugaring.
// We want to check unsafety against the source info of the
@ -244,7 +272,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
self.source_info = self.mir.local_decls[local].source_info;
}
}
let base_ty = base.ty(self.mir, self.tcx).ty;
let base_ty = proj.base.ty(self.mir, self.tcx).ty;
match base_ty.sty {
ty::RawPtr(..) => {
self.require_unsafe("dereference of raw pointer",
@ -260,8 +288,8 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
MutatingUseContext::AsmOutput
)
{
let elem_ty = match elem {
&ProjectionElem::Field(_, ty) => ty,
let elem_ty = match proj.elem {
ProjectionElem::Field(_, ty) => ty,
_ => span_bug!(
self.source_info.span,
"non-field projection {:?} from union?",
@ -292,36 +320,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
}
self.source_info = old_source_info;
}
&Place::Base(PlaceBase::Local(..)) => {
// locals are safe
}
&Place::Base(PlaceBase::Static(box Static { kind: StaticKind::Promoted(_), .. })) => {
bug!("unsafety checking should happen before promotion")
}
&Place::Base(
PlaceBase::Static(box Static { kind: StaticKind::Static(def_id), .. })
) => {
if self.tcx.is_mutable_static(def_id) {
self.require_unsafe("use of mutable static",
"mutable statics can be mutated by multiple threads: aliasing violations \
or data races will cause undefined behavior",
UnsafetyViolationKind::General);
} else if self.tcx.is_foreign_item(def_id) {
let source_info = self.source_info;
let lint_root =
self.source_scope_local_data[source_info.scope].lint_root;
self.register_violations(&[UnsafetyViolation {
source_info,
description: InternedString::intern("use of extern static"),
details: InternedString::intern(
"extern statics are not controlled by the Rust type system: invalid \
data, aliasing violations or data races will cause undefined behavior"),
kind: UnsafetyViolationKind::ExternStatic(lint_root)
}], &[]);
}
}
};
self.super_place(place, context, location);
});
}
}