gcc:
	* system.h [__cplusplus]: Wrap C function declarations in extern "C".

	include:
	* xregex.h (regoff_t): Define.

From-SVN: r176747

* xregex.h (_REGEX_RE_COMP): Define.
(re_comp): Define to xre_comp.
(re_exec): Define to xre_exec.

From-SVN: r44585

* xregex.h: New file to support libiberty regex.
* xregex2.h: Ditto.

From-SVN: r43913