diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs
index 56a320c8d3b..f251127b46c 100644
--- a/compiler/rustc_feature/src/active.rs
+++ b/compiler/rustc_feature/src/active.rs
@@ -692,7 +692,6 @@ pub const INCOMPLETE_FEATURES: &[Symbol] = &[
     sym::capture_disjoint_fields,
     sym::inherent_associated_types,
     sym::type_alias_impl_trait,
-    sym::rustc_insignificant_dtor,
     sym::unnamed_fields,
 ];
 
diff --git a/src/test/ui/feature-gates/rustc_insignificant_dtor.rs b/src/test/ui/feature-gates/rustc_insignificant_dtor.rs
new file mode 100644
index 00000000000..b3b214a7ce2
--- /dev/null
+++ b/src/test/ui/feature-gates/rustc_insignificant_dtor.rs
@@ -0,0 +1,2 @@
+#![feature(rustc_insignificant_dtor)] //~ ERROR unknown feature `rustc_insignificant_dtor`
+fn main() {}
diff --git a/src/test/ui/feature-gates/rustc_insignificant_dtor.stderr b/src/test/ui/feature-gates/rustc_insignificant_dtor.stderr
new file mode 100644
index 00000000000..560e27e34bc
--- /dev/null
+++ b/src/test/ui/feature-gates/rustc_insignificant_dtor.stderr
@@ -0,0 +1,9 @@
+error[E0635]: unknown feature `rustc_insignificant_dtor`
+  --> $DIR/rustc_insignificant_dtor.rs:1:12
+   |
+LL | #![feature(rustc_insignificant_dtor)]
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0635`.