Remove dead code

crates/compiler/mono/src/layout.rs

@@ -2351,41 +2351,6 @@ impl<'a> Layout<'a> {
         false // TODO this should use is_zero_sized once doing so doesn't break things!
     }
 
-    /// Like stack_size, but doesn't require target info because
-    /// whether something is zero sized is not target-dependent.
-    #[allow(dead_code)]
-    fn is_zero_sized(&self) -> bool {
-        match self {
-            // There are no zero-sized builtins
-            Layout::Builtin(_) => false,
-            // Functions are never zero-sized
-            Layout::LambdaSet(_) => false,
-            // Empty structs, or structs with all zero-sized fields, are zero-sized
-            Layout::Struct { field_layouts, .. } => field_layouts.iter().all(Self::is_zero_sized),
-            // A Box that points to nothing should be unwrapped
-            Layout::Boxed(content) => content.is_zero_sized(),
-            Layout::Union(union_layout) => match union_layout {
-                UnionLayout::NonRecursive(tags)
-                | UnionLayout::Recursive(tags)
-                | UnionLayout::NullableWrapped {
-                    other_tags: tags, ..
-                } => tags
-                    .iter()
-                    .all(|payloads| payloads.iter().all(Self::is_zero_sized)),
-                UnionLayout::NonNullableUnwrapped(tags)
-                | UnionLayout::NullableUnwrapped {
-                    other_fields: tags, ..
-                } => tags.iter().all(Self::is_zero_sized),
-            },
-            // Recursive pointers are considered zero-sized because
-            // if you have a recursive data structure where everything
-            // else but the recutsive pointer is zero-sized, then
-            // the whole thing is unnecessary at runtime and should
-            // be zero-sized.
-            Layout::RecursivePointer => true,
-        }
-    }
-
     pub fn is_passed_by_reference<I>(&self, interner: &I, target_info: TargetInfo) -> bool
     where
         I: Interner<'a, Layout<'a>>,