diff --git a/taglib/taglib.pro b/taglib/taglib.pro
index 188179a4..a98727d9 100644
--- a/taglib/taglib.pro
+++ b/taglib/taglib.pro
@@ -6,7 +6,7 @@ TEMPLATE = lib
 CONFIG += lib_bundle
 CONFIG += x86 ppc
 CONFIG -= qt
-DEFINES += HAVE_ZLIB=1
+DEFINES += HAVE_ZLIB=1 NDEBUG
 LIBS += -lz
 TARGET = TagLib
 VERSION = 1.5