gcc.c (option_map): New flag -no-canonical-prefixes.
* gcc.c (option_map): New flag -no-canonical-prefixes.
* (display_help): Print help text for new flag.
* (process_command): Move options translation and language specifics
and handle new flag early. Use it to set a function pointer to a
prefix builder. Replace make_relative_prefix calls with calls to
the function pointed to. Ignore new flag in regular options handling.
* doc/invoke.texi (Overall Options): Documented -no-canonical-prefixes.
From-SVN: r149702