* ggc-simple.c (IS_MARKED, IGNORE_MARK): New.
(GGC_ANY_MAGIC, GGC_ANY_MAGIC_MARK): New.
(struct ggc_any): Replace `mark' with `magic_mark'.
(ggc_alloc_string): Use memcpy, not bcopy.
(ggc_alloc_any): Set magic_mark. Update bytes_alloced_since_gc.
(ggc_free_{rtx,rtvec,tree,string}): Mark inline.
(ggc_free_any): New.
(ggc_mark_string): Use IGNORE_MARK. Calc back to struct gcc_string.
(ggc_mark): Use IGNORE_MARK. Abort if magic doesn't match.
(ggc_collect): Re-enable collection avoidance. Use GGC_ANY_MARK.
Use IS_MARKED. Use ggc_free_any.