diff --git a/its/tests/projects/sample-c/src/file.c b/its/tests/projects/sample-c/src/file.c
index 852f9645e7..b51df2c060 100644
--- a/its/tests/projects/sample-c/src/file.c
+++ b/its/tests/projects/sample-c/src/file.c
@@ -1,2 +1,4 @@
+void end_of_preamble();
+
 #import "foo.h" // Noncompliant