libstdc++.exp (check_v3_target_time): Discard unused compilation result thanks to...

libstdc++.exp (check_v3_target_time): Discard unused compilation result thanks to /dev/null.

2011-04-22  François Dumont  <francois.cppdevs@free.fr>

        * testsuite/lib/libstdc++.exp (check_v3_target_time): Discard
        unused compilation result thanks to /dev/null.
        * testsuite/lib/libstdc++.exp (check_v3_target_debug_mode
        check_v3_target_profile_mode check_v3_target_normal_mode
        check_v3_target_cstdint check_v3_target_cmath
        check_v3_target_atomic_builtins check_v3_target_gthreads
        check_v3_target_nanosleep check_v3_target_sched_yield
        check_v3_target_string_conversions check_v3_target_swprintf
        check_v3_target_binary_io): Use simple preprocessing rather than
        compilation. Discard unused preprocessing result thanks to /dev/null.

From-SVN: r172872