diff --git a/src/config-win32.h b/src/config-win32.h
index 42264ecffd..ba60773eb0 100644
--- a/src/config-win32.h
+++ b/src/config-win32.h
@@ -10,3 +10,6 @@
 
 /* Define if you have the <io.h> header file.  */
 #define HAVE_IO_H 1
+ 
+/* Define if you have the strdup function.  */
+#define HAVE_STRDUP 1