diff --git a/Makefile.am b/Makefile.am
index 062feb42..9514cc59 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -82,6 +82,7 @@ libdrm_la_LIBADD = @CLOCK_LIB@
 
 libdrm_la_CPPFLAGS = -I$(top_srcdir)/include/drm
 AM_CFLAGS = \
+	$(WARN_CFLAGS) \
 	$(VALGRIND_CFLAGS)
 
 libdrm_la_SOURCES = $(LIBDRM_FILES)
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 37b8d3a1..f989d8e4 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,6 +1,7 @@
 NULL:=#
 
-AM_CPPFLAGS = \
+AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I $(top_srcdir)/include/drm \
 	-I $(top_srcdir)
 
diff --git a/tests/exynos/Makefile.am b/tests/exynos/Makefile.am
index 92de4e4b..b21d0169 100644
--- a/tests/exynos/Makefile.am
+++ b/tests/exynos/Makefile.am
@@ -1,4 +1,5 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I $(top_srcdir)/include/drm \
 	-I $(top_srcdir)/libkms/ \
 	-I $(top_srcdir)/exynos \
diff --git a/tests/kmstest/Makefile.am b/tests/kmstest/Makefile.am
index 7903a267..fd21e612 100644
--- a/tests/kmstest/Makefile.am
+++ b/tests/kmstest/Makefile.am
@@ -1,4 +1,5 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I$(top_srcdir)/include/drm \
 	-I$(top_srcdir)/libkms/ \
 	-I$(top_srcdir)
diff --git a/tests/modeprint/Makefile.am b/tests/modeprint/Makefile.am
index 6420ef33..895805fd 100644
--- a/tests/modeprint/Makefile.am
+++ b/tests/modeprint/Makefile.am
@@ -1,4 +1,5 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I$(top_srcdir)/include/drm \
 	-I$(top_srcdir)
 
diff --git a/tests/proptest/Makefile.am b/tests/proptest/Makefile.am
index f81a3c00..48a84c1e 100644
--- a/tests/proptest/Makefile.am
+++ b/tests/proptest/Makefile.am
@@ -1,4 +1,5 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I$(top_srcdir)/include/drm \
 	-I$(top_srcdir)
 
diff --git a/tests/radeon/Makefile.am b/tests/radeon/Makefile.am
index 1775669e..d18620da 100644
--- a/tests/radeon/Makefile.am
+++ b/tests/radeon/Makefile.am
@@ -1,4 +1,5 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I $(top_srcdir)/include/drm \
 	-I $(top_srcdir)
 
diff --git a/tests/tegra/Makefile.am b/tests/tegra/Makefile.am
index ca63d92f..8e625c8f 100644
--- a/tests/tegra/Makefile.am
+++ b/tests/tegra/Makefile.am
@@ -3,7 +3,7 @@ AM_CPPFLAGS = \
 	-I$(top_srcdir)/tegra \
 	-I$(top_srcdir)
 
-AM_CFLAGS = -Wall -Werror
+AM_CFLAGS = $(WARN_CFLAGS)
 
 LDADD = \
 	../../tegra/libdrm_tegra.la \
diff --git a/tests/vbltest/Makefile.am b/tests/vbltest/Makefile.am
index 34a35e7d..4d87887a 100644
--- a/tests/vbltest/Makefile.am
+++ b/tests/vbltest/Makefile.am
@@ -1,6 +1,8 @@
 AM_CFLAGS = \
+	$(WARN_CFLAGS)\
 	-I$(top_srcdir)/include/drm \
 	-I$(top_srcdir)
+
 if HAVE_INSTALL_TESTS
 bin_PROGRAMS = \
 	vbltest