diff --git a/mozilla/js2/tests/cpp/macbuild/js2.pbproj/project.pbxproj b/mozilla/js2/tests/cpp/macbuild/js2.pbproj/project.pbxproj
index 86c0f9e4956..c76deb75c8a 100644
--- a/mozilla/js2/tests/cpp/macbuild/js2.pbproj/project.pbxproj
+++ b/mozilla/js2/tests/cpp/macbuild/js2.pbproj/project.pbxproj
@@ -135,7 +135,7 @@
 				INSTALL_PATH = "$(HOME)/bin";
 				LIBRARY_SEARCH_PATHS = "";
 				OPTIMIZATION_CFLAGS = "-O0";
-				OTHER_CFLAGS = "-DXP_UNIX=1 -DDARWIN=1";
+				OTHER_CFLAGS = "-DXP_UNIX=1 -DDARWIN=1 -DDEBUG=1";
 				OTHER_LDFLAGS = "";
 				OTHER_REZFLAGS = "";
 				PRODUCT_NAME = js2;