diff --git a/src/libsysprof-profile/tests/test-profiler.c b/src/libsysprof-profile/tests/test-profiler.c
index af88276a..1ac31e10 100644
--- a/src/libsysprof-profile/tests/test-profiler.c
+++ b/src/libsysprof-profile/tests/test-profiler.c
@@ -226,6 +226,8 @@ main (int   argc,
         sysprof_capture_writer_cat (writer, reader);
     }
 
+  sysprof_capture_writer_flush (writer);
+
   g_clear_pointer (&reader, sysprof_capture_reader_unref);
   g_clear_pointer (&writer, sysprof_capture_writer_unref);