diff --git a/xpcom/tests/Makefile.in b/xpcom/tests/Makefile.in
index b5eaf93c590c..f8a020e1214d 100644
--- a/xpcom/tests/Makefile.in
+++ b/xpcom/tests/Makefile.in
@@ -29,7 +29,7 @@ CPPSRCS = \
 	TestFactory.cpp	\
 	$(NULL)
 
-INCLUDES=-I$(srcdir)/../src -I$(DIST)/include
+INCLUDES=-I$(srcdir)/../public -I$(DIST)/include
 
 ifndef NO_SHARED_LIB
 DIRS = dynamic