diff --git a/test/Makefile.am b/test/Makefile.am
index 971d9739..2e7e05d6 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -72,7 +72,7 @@ unit_tests_LDFLAGS = \
 
 unit_tests_CPPFLAGS = \
 	-Icommon \
-	-I$(srcdir)/../ \
+	-I$(top_srcdir)/ \
 	-g \
 	-I$(top_builddir)/headers \
 	$(CURL_CFLAGS) \
@@ -127,7 +127,7 @@ regression_tests_LDFLAGS = \
 
 regression_tests_CPPFLAGS = \
 	-Icommon \
-	-I$(srcdir)../ \
+	-I$(top_srcdir) \
 	-g \
 	-I$(top_builddir)/headers \
 	$(CURL_CFLAGS) \
@@ -179,7 +179,7 @@ rules_optimization_LDFLAGS = \
 
 rules_optimization_CPPFLAGS = \
 	-Icommon \
-	-I$(srcdir)/../ \
+	-I$(top_srcdir)/ \
 	-g \
 	-I$(top_builddir)/headers \
 	$(CURL_CFLAGS) \