2 files changed, 3 insertions, 2 deletions
diff --git a/compiler/rustc_abi/src/layout.rs b/compiler/rustc_abi/src/layout.rs
index aea88641f82..489a8403c3b 100644
--- a/compiler/rustc_abi/src/layout.rs
+++ b/compiler/rustc_abi/src/layout.rs
@@ -763,7 +763,9 @@ pub trait LayoutCalculator {
         let mut size = Size::ZERO;
         let only_variant = &variants[FIRST_VARIANT];
         for field in only_variant {
-            assert!(field.0.is_sized());
+            if field.0.is_unsized() {
+                self.delay_bug("unsized field in union".to_string());
+            }
 
             align = align.max(field.align());
             max_repr_align = max_repr_align.max(field.max_repr_align());
diff --git a/compiler/rustc_abi/src/lib.rs b/compiler/rustc_abi/src/lib.rs
index ef0c763ac20..93b29d037d6 100644
--- a/compiler/rustc_abi/src/lib.rs
+++ b/compiler/rustc_abi/src/lib.rs
@@ -1345,7 +1345,6 @@ impl Abi {
 
     /// Discard validity range information and allow undef.
     pub fn to_union(&self) -> Self {
-        assert!(self.is_sized());
         match *self {
             Abi::Scalar(s) => Abi::Scalar(s.to_union()),
             Abi::ScalarPair(s1, s2) => Abi::ScalarPair(s1.to_union(), s2.to_union()),