* ggc.h (rtvec_def): Forward declare.
        (tree_node): Likewise.
        (ggc_root): Define.
        (roots): Declare.
        (ggc_set_mark_rtx): Add prototype.
        (ggc_set_mark_rtvec): Likewise.
        (ggc_set_mark_tree): Likewise.
        * ggc-simple.c (ggc_root): Don't define.
        (roots): Don't declare.
        (ggc_mark_rtx): Remove.
        (ggc_mark_rtvec): Likewise.
        (ggc_mark_tree): Likewise.
        (ggc_mark_varray): Likewise.
        (ggc_mark_tree_hash_table_entry): Likewise.
        (ggc_mark_tree_hash_table): Likewise.
        (ggc_set_mart_rtx): New function.
        (ggc_set_mark_rtvec): Likewise.
        (ggc_set_mark_tree): Likewise.
        (ggc_add_root): Remove.
        (ggc_add_rtx_root): Likewise.
        (ggc_remove_tree_root): Likewise.
        (ggc_add_string_root): Likewise.
        (ggc_add_tree_varray_root): Likewise.
        (ggc_add_tree_hash_table_root): Likewise.
        (ggc_del_root): Likewise.
        (ggc_mark_rtx_ptr): Likewise.
        (ggc_mark_tree_ptr): Likewise.
        (ggc_mark_string_ptr): Likewise.
        (ggc_mark_tree_varray_ptr): Likewise.
        (ggc_mark_tree_hash_table_ptr): Likewise.
        * ggc-common.c: New file.
        * Makefile.in (OBJS): Add ggc-common.o.
        (ggc-common.o): List dependencies.

From-SVN: r29281