diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index d0b1e8bcf7b..ca9b61a80af 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -2,6 +2,7 @@
 
 	* configure.ac: Check size of size_t.
 	* configure: Regenerate.
+	* config.in: Regenerate.
 
 2015-11-09  Alan Modra  <amodra@gmail.com>
 
diff --git a/libiberty/config.in b/libiberty/config.in
index 0dedbf08e0f..1ff50c67f60 100644
--- a/libiberty/config.in
+++ b/libiberty/config.in
@@ -470,6 +470,9 @@
 /* The size of `long long', as computed by sizeof. */
 #undef SIZEOF_LONG_LONG
 
+/* The size of `size_t', as computed by sizeof. */
+#undef SIZEOF_SIZE_T
+
 /* Define if you know the direction of stack growth for your system; otherwise
    it will be automatically deduced at run-time. STACK_DIRECTION > 0 => grows
    toward higher addresses STACK_DIRECTION < 0 => grows toward lower addresses