2019-01-28  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        * common.opt (-Wattribute-alias): Remove "no-" from name.
        Make -Wattribute-alias command line option and
        #pragma GCC diagnostic ignored "-Wattribute-alias" work again.

testsuite:
2019-01-28  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        * gcc.dg/Wattribute-alias.c: Add test for #pragma GCC diagnostic ignored
        "-Wattribute-alias".

From-SVN: r268336