+2015-04-01 H.J. Lu <hongjiu.lu@intel.com>
+
+ * zlib.m4 (AM_ZLIB): Unset zlibdir and zlibinc only for
+ --with-system-zlib.
+
+2015-03-31 H.J. Lu <hongjiu.lu@intel.com>
+
+ * zlib.m4 (AM_ZLIB): Replace --with-zlib with --with-system-zlib.
+
2015-03-16 H.J. Lu <hongjiu.lu@intel.com>
* isl.m4: Sync with GCC tree.