Warning fixes:

Warning fixes:
        * class.c (build_utf8_ref): Initialize variable `field'.
        * decl.c (init_decl_processing): Initialize variable `field'.
        * expr.c (build_known_method_ref): Mark parameters `method_type',
        `method_signature' and `arg_list' with ATTRIBUTE_UNUSED.
        (process_jvm_instruction): Likewise for parameter `length'.
        * jvspec.c (lang_specific_driver): Mark variables `saw_math',
        `saw_libc', `saw_gc', `saw_threadlib' and `saw_libgcj' with
        ATTRIBUTE_UNUSED.
        * parse.y (maybe_generate_clinit): Remove unused variable
        `has_non_primitive_fields'.
        (find_in_imports_on_demand): Initialize variables `node_to_use'
        and `cl'.
        (patch_binop): Likewise for variable `prom_type'.
        (patch_unaryop): Likewise for variable `prom_type'.
        * verify.c (verify_jvm_instructions): Likewise for variable `last'.
        * xref.c (xref_table): Add missing initializer.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@27030 138bc75d-0d04-0410-961f-82ee72b054a4