fix a strange ConstProp ICE

rust-lang · Jul 6, 2022 · dc9e0bf · dc9e0bf
1 parent e685530
commit dc9e0bf
Show file tree

Hide file tree

Showing 2 changed files with 10 additions and 2 deletions.
diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -393,7 +393,11 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
             .layout_of(EarlyBinder(body.return_ty()).subst(tcx, substs))
             .ok()
             // Don't bother allocating memory for large values.
-            .filter(|ret_layout| ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT))
+            // I don't know how return types can seem to be unsized but this happens in the
+            // `type/type-unsatisfiable.rs` test.
+            .filter(|ret_layout| {
+                !ret_layout.is_unsized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
+            })
             .unwrap_or_else(|| ecx.layout_of(tcx.types.unit).unwrap());
 
         let ret = ecx

diff --git a/compiler/rustc_mir_transform/src/const_prop_lint.rs b/compiler/rustc_mir_transform/src/const_prop_lint.rs
@@ -387,7 +387,11 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
             .layout_of(EarlyBinder(body.return_ty()).subst(tcx, substs))
             .ok()
             // Don't bother allocating memory for large values.
-            .filter(|ret_layout| ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT))
+            // I don't know how return types can seem to be unsized but this happens in the
+            // `type/type-unsatisfiable.rs` test.
+            .filter(|ret_layout| {
+                !ret_layout.is_unsized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
+            })
             .unwrap_or_else(|| ecx.layout_of(tcx.types.unit).unwrap());
 
         let ret = ecx