diff --git a/src/test/ui/lint/known-tool-in-submodule/root.rs b/src/test/ui/lint/known-tool-in-submodule/root.rs
new file mode 100644
index 00000000000..80806dcbd28
--- /dev/null
+++ b/src/test/ui/lint/known-tool-in-submodule/root.rs
@@ -0,0 +1,10 @@
+// check-pass
+
+#![feature(register_tool)]
+#![register_tool(tool)]
+
+mod submodule;
+
+fn main() {
+    submodule::foo();
+}
diff --git a/src/test/ui/lint/known-tool-in-submodule/submodule.rs b/src/test/ui/lint/known-tool-in-submodule/submodule.rs
new file mode 100644
index 00000000000..bb25e10056f
--- /dev/null
+++ b/src/test/ui/lint/known-tool-in-submodule/submodule.rs
@@ -0,0 +1,4 @@
+// ignore-test: not a test
+
+#[allow(tool::lint)]
+pub fn foo() {}