omp-low.c (optimize_omp_library_calls): Use types_compatible_p instead of comparing TYPE_MAIN_VARIANT for equality.

        * omp-low.c (optimize_omp_library_calls): Use types_compatible_p
        instead of comparing TYPE_MAIN_VARIANT for equality.
        * tree-vect-patterns.c (vect_recog_dot_prod_pattern,
        vect_recog_widen_mult_pattern, vect_recog_widen_sum_pattern): Ditto.
        * tree-vect-loop.c (vect_is_simple_reduction): Ditto.
        * gimplify.c (goa_lhs_expr_p): Ditto and use
        STRIP_USELESS_TYPE_CONVERSION.

From-SVN: r150936