nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2025-05-02 13:07:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

generator fields are not necessarily initialized

Browse Source
This commit is contained in:
Ralf Jung 2018-11-20 15:08:26 +01:00
parent 046e054a99
commit 6eeedbcd70
1 changed files with 22 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
src/librustc_mir/interpret/visitor.rs
View File

@ -142,6 +142,7 @@ macro_rules! make_value_visitor {
self.walk_value(v) self.walk_value(v)
} }
/// Visit the given value as a union. No automatic recursion can happen here. /// Visit the given value as a union. No automatic recursion can happen here.
/// Also called for the fields of a generator, which may or may not be initialized.
#[inline(always)] #[inline(always)]
fn visit_union(&mut self, _v: Self::V) -> EvalResult<'tcx> fn visit_union(&mut self, _v: Self::V) -> EvalResult<'tcx>
{ {
@ -291,17 +292,28 @@ macro_rules! make_value_visitor {
// use that as an unambiguous signal for detecting primitives. Make sure // use that as an unambiguous signal for detecting primitives. Make sure
// we did not miss any primitive. // we did not miss any primitive.
debug_assert!(fields > 0); debug_assert!(fields > 0);
self.visit_union(v)?; self.visit_union(v)
}, },
layout::FieldPlacement::Arbitrary { ref offsets, .. } => { layout::FieldPlacement::Arbitrary { ref offsets, .. } => {
// FIXME: We collect in a vec because otherwise there are lifetime errors: // Special handling needed for generators: All but the first field
// Projecting to a field needs (mutable!) access to `ecx`. // (which is the state) are actually implicitly `MaybeUninit`, i.e.,
// they may or may not be initialized, so we cannot visit them.
match v.layout().ty.sty {
ty::Generator(..) => {
let field = v.project_field(self.ecx(), 0)?;
self.visit_aggregate(v, std::iter::once(Ok(field)))
}
_ => {
// FIXME: We collect in a vec because otherwise there are lifetime
// errors: Projecting to a field needs access to `ecx`.
let fields: Vec<EvalResult<'tcx, Self::V>> = let fields: Vec<EvalResult<'tcx, Self::V>> =
(0..offsets.len()).map(|i| { (0..offsets.len()).map(|i| {
v.project_field(self.ecx(), i as u64) v.project_field(self.ecx(), i as u64)
}) })
.collect(); .collect();
self.visit_aggregate(v, fields.into_iter())?; self.visit_aggregate(v, fields.into_iter())
}
}
}, },
layout::FieldPlacement::Array { .. } => { layout::FieldPlacement::Array { .. } => {
// Let's get an mplace first. // Let's get an mplace first.
@ -317,10 +329,9 @@ macro_rules! make_value_visitor {
.map(|f| f.and_then(|f| { .map(|f| f.and_then(|f| {
Ok(Value::from_mem_place(f)) Ok(Value::from_mem_place(f))
})); }));
self.visit_aggregate(v, iter)?; self.visit_aggregate(v, iter)
} }
} }
Ok(())
} }
} }
} }