portability fixes
diff --git a/config.h.in b/config.h.in
index 1910711..0133b2b 100644
--- a/config.h.in
+++ b/config.h.in
@@ -1,7 +1,7 @@
/* config.h.in. Generated from configure.in by autoheader. */
-/* Define to 1 if you have the <errno.h> header file. */
-#undef HAVE_ERRNO_H
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
/* Define to 1 if you have the <inttypes.h> header file. */
#undef HAVE_INTTYPES_H
@@ -9,6 +9,9 @@
/* Define to 1 if you have the <memory.h> header file. */
#undef HAVE_MEMORY_H
+/* Define to 1 if you have the `mergesort' function. */
+#undef HAVE_MERGESORT
+
/* Define to 1 if you have the <stdint.h> header file. */
#undef HAVE_STDINT_H
@@ -27,6 +30,9 @@
/* Define to 1 if you have the `strtoll' function. */
#undef HAVE_STRTOLL
+/* Define to 1 if you have the <sys/param.h> header file. */
+#undef HAVE_SYS_PARAM_H
+
/* Define to 1 if you have the <sys/stat.h> header file. */
#undef HAVE_SYS_STAT_H