Fix ICE with `#[repr(simd)]` on enum

1 files changed, 9 insertions, 0 deletions

diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index 28a44b09de2..6b1ec1b0646 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -672,6 +672,15 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
 
             // SIMD vector types.
             ty::Adt(def, substs) if def.repr.simd() => {
+                if !def.is_struct() {
+                    // Should have yielded E0517 by now.
+                    tcx.sess.delay_span_bug(
+                        DUMMY_SP,
+                        "#[repr(simd)] was applied to an ADT that is not a struct",
+                    );
+                    return Err(LayoutError::Unknown(ty));
+                }
+
                 // Supported SIMD vectors are homogeneous ADTs with at least one field:
                 //
                 // * #[repr(simd)] struct S(T, T, T, T);