diff --git a/libtiff/config.h.in b/libtiff/config.h.in
index 97d51212..471e330c 100644
--- a/libtiff/config.h.in
+++ b/libtiff/config.h.in
@@ -102,7 +102,7 @@
 /* Define to 1 if the system has the type `_Bool'. */
 #undef HAVE__BOOL
 
-/* Set the native cpu bit order */
+/* Set the native cpu bit order (possible values are msb2lsb and lsb2msb) */
 #undef HOST_FILLORDER
 
 /* Name of package */
@@ -148,6 +148,12 @@
 /* Define to empty if `const' does not conform to ANSI C. */
 #undef const
 
+/* Define to `__inline__' or `__inline' if that's what the C compiler
+   calls it, or to nothing if 'inline' is not supported under any name.  */
+#ifndef __cplusplus
+#undef inline
+#endif
+
 /* Define to `long' if <sys/types.h> does not define. */
 #undef off_t