diff --git a/libcelt/tests/mathops-test.c b/libcelt/tests/mathops-test.c
index ef25f5d0600c722531b4c3382a4f9d6bd3fa08ea..b4eb3c0bb8cb29d500bec94a68ba89de2e4ec9c3 100644
--- a/libcelt/tests/mathops-test.c
+++ b/libcelt/tests/mathops-test.c
@@ -2,6 +2,8 @@
 #include "config.h"
 #endif
 
+#define CELT_C
+
 #include "mathops.c"
 #include "entenc.c"
 #include "entdec.c"