+# Set directory with CPU-specific optimization
+cpu_opt_dir=${cpu_include_dir}/opt
+test -d ${glibcxx_srcdir}/config/${cpu_include_dir}/opt ||
+cpu_opt_dir=cpu/generic/opt
+# For each header with CPU-specific optimizations check whether it
+# exists in ${cpu_opt_dir}. If not, point the variable at the
+# appropriate file in the generic directory.
+cpu_opt_ext_random=${cpu_opt_dir}/ext/opt_random.h
+test -f ${glibcxx_srcdir}/config/${cpu_opt_ext_random} ||
+cpu_opt_ext_random=cpu/generic/opt/ext/opt_random.h
+
+cpu_opt_bits_random=${cpu_opt_dir}/bits/opt_random.h
+test -f ${glibcxx_srcdir}/config/${cpu_opt_ext_random} ||
+cpu_opt_ext_random=cpu/generic/opt/bits/opt_random.h
+
+