diff --git a/tests/Makefile.am b/tests/Makefile.am
index f64fc107..5f2884df 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -30,7 +30,7 @@ OBJECTS = main.c spdylay_pq_test.c spdylay_map_test.c spdylay_queue_test.c \
 	spdylay_frame_test.c
 
 HFILES = spdylay_pq_test.h spdylay_map_test.h spdylay_queue_test.h \
-	spdylay_buffer_test.h spdylay_zlib_test.h spdylay_session_test.h
+	spdylay_buffer_test.h spdylay_zlib_test.h spdylay_session_test.h \
 	spdylay_frame_test.h
 
 main_SOURCES = $(HFILES) $(OBJECTS)