diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
index 3b62148abb7..8ef25d4e2ff 100644
--- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
@@ -93,23 +93,26 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     return;
                 }
 
-                if let OperandValue::Immediate(v) = cg_elem.val {
-                    let start = dest.val.llval;
-                    let size = bx.const_usize(dest.layout.size.bytes());
+                match cg_elem.val {
+                    OperandValue::Immediate(v) => {
+                        let start = dest.val.llval;
+                        let size = bx.const_usize(dest.layout.size.bytes());
 
-                    // Use llvm.memset.p0i8.* to initialize all zero arrays
-                    if bx.cx().const_to_opt_u128(v, false) == Some(0) {
-                        let fill = bx.cx().const_u8(0);
-                        bx.memset(start, fill, size, dest.val.align, MemFlags::empty());
-                        return;
-                    }
+                        // Use llvm.memset.p0i8.* to initialize all zero arrays
+                        if bx.cx().const_to_opt_u128(v, false) == Some(0) {
+                            let fill = bx.cx().const_u8(0);
+                            bx.memset(start, fill, size, dest.val.align, MemFlags::empty());
+                            return;
+                        }
 
-                    // Use llvm.memset.p0i8.* to initialize byte arrays
-                    let v = bx.from_immediate(v);
-                    if bx.cx().val_ty(v) == bx.cx().type_i8() {
-                        bx.memset(start, v, size, dest.val.align, MemFlags::empty());
-                        return;
+                        // Use llvm.memset.p0i8.* to initialize byte arrays
+                        let v = bx.from_immediate(v);
+                        if bx.cx().val_ty(v) == bx.cx().type_i8() {
+                            bx.memset(start, v, size, dest.val.align, MemFlags::empty());
+                            return;
+                        }
                     }
+                    _ => (),
                 }
 
                 let count = self