diff --git a/Mac/Include/macglue.h b/Mac/Include/macglue.h
index dd3c28abe2f..dae4879cb2a 100644
--- a/Mac/Include/macglue.h
+++ b/Mac/Include/macglue.h
@@ -119,9 +119,7 @@ void PyMac_InitApplet(void);
 
 /* from macgetargv: */
 OSErr PyMac_init_process_location(void);
-#ifndef HAVE_STRDUP
 char *	strdup(const char *str);
-#endif
 
 #ifdef USE_GUSI2
 /* from pyGUSISIOUX.cp */
diff --git a/Mac/Include/pyconfig.h b/Mac/Include/pyconfig.h
index dc79dcbea86..ac4e15a9612 100644
--- a/Mac/Include/pyconfig.h
+++ b/Mac/Include/pyconfig.h
@@ -576,7 +576,7 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #undef HAVE_STATVFS
 
 /* Define if you have the strdup function.  */
-#undef HAVE_STRDUP
+#define HAVE_STRDUP
 
 /* Define if you have the strerror function.  */
 #define HAVE_STRERROR