bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

skip all refs-to-uninit-local, not just arguments

Browse source
This commit is contained in:
Ralf Jung 2019-10-19 18:16:22 +02:00
parent 282403e6bd
commit f907fbe1a6
1 changed files with 6 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

11
src/librustc_mir/transform/const_prop.rs
View file

@ -523,18 +523,19 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
// local. There's nothing it can do here: taking a reference needs an allocation // local. There's nothing it can do here: taking a reference needs an allocation
// which needs to know the size. Normally that's okay as during execution // which needs to know the size. Normally that's okay as during execution
// (e.g. for CTFE) it can never happen. But here in const_prop // (e.g. for CTFE) it can never happen. But here in const_prop
// we leave function arguments uninitialized, so if one of these is unsized // unknown data is uninitialized, so if e.g. a function argument is unsized
// and has a reference taken, we get an ICE. // and has a reference taken, we get an ICE.
Rvalue::Ref(_, _, Place { base: PlaceBase::Local(local), projection: box [] }) => { Rvalue::Ref(_, _, Place { base: PlaceBase::Local(local), projection: box [] }) => {
trace!("checking Ref({:?})", place); trace!("checking Ref({:?})", place);
let alive = let alive =
if let LocalValue::Live(_) = self.ecx.frame().locals[*local].value { if let LocalValue::Live(_) = self.ecx.frame().locals[*local].value {
true true
} else { false }; } else {
false
};
// local 0 is the return place; locals 1..=arg_count are the arguments. if !alive {
if local.as_usize() <= self.ecx.frame().body.arg_count && !alive { trace!("skipping Ref({:?}) to uninitialized local", place);
trace!("skipping Ref({:?})", place);
return None; return None;
} }
} }