diff --git a/pyconfig.h.in b/pyconfig.h.in
index 1ba3e58..26197fb 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -85,6 +85,9 @@
 /* Define to 1 if you have the <conio.h> header file. */
 #undef HAVE_CONIO_H
 
+/* Define to 1 if you have the `copysign' function. */
+#undef HAVE_COPYSIGN
+
 /* Define to 1 if you have the `ctermid' function. */
 #undef HAVE_CTERMID
 
@@ -288,6 +291,15 @@
 /* Define to 1 if you have the <io.h> header file. */
 #undef HAVE_IO_H
 
+/* Define to 1 if you have the `isfinite' function. */
+#undef HAVE_ISFINITE
+
+/* Define to 1 if you have the `isinf' function. */
+#undef HAVE_ISINF
+
+/* Define to 1 if you have the `isnan' function. */
+#undef HAVE_ISNAN
+
 /* Define to 1 if you have the `kill' function. */
 #undef HAVE_KILL
 
@@ -1028,3 +1040,4 @@
 
 #endif /*Py_PYCONFIG_H*/
 
+