diff --git a/src/if_perl.xs b/src/if_perl.xs
index 19292b3..b429b47 100644
--- a/src/if_perl.xs
+++ b/src/if_perl.xs
@@ -611,7 +611,7 @@
 perl_enabled(verbose)
     int		verbose;
 {
-#if WIN3264
+#ifdef WIN3264
     char *dll = DYNAMIC_PERL_DLL;
 #else
     char *dll = *p_perldll ? (char *)p_perldll : DYNAMIC_PERL_DLL;