diff --git a/repos/libports/src/test/ada_secondary_stack/target.mk b/repos/libports/src/test/ada_secondary_stack/target.mk
index 393a7c525..254cc8798 100644
--- a/repos/libports/src/test/ada_secondary_stack/target.mk
+++ b/repos/libports/src/test/ada_secondary_stack/target.mk
@@ -2,3 +2,5 @@ TARGET   = test-ada_secondary_stack
 SRC_ADB  = stack.adb
 SRC_CC   = main.cc
 LIBS     = base ada
+
+INC_DIR += $(PRG_DIR)