2006-10-31  Hristian Kirtchev  <kirtchev@adacore.com>
	    Jose Ruiz  <ruiz@adacore.com>

	* a-calend-vms.adb (Leap_Sec_Ops): Temp body for package in private
	part of Ada.Calendar: all subprogram raise Unimplemented.
	(Split_W_Offset): Temp function body, raising Unimplemented

	* a-calend.ads, a-calend-vms.ads: 
	Add imported variable Invalid_TZ_Offset used to designate targets unable
	to support time zones.
	(Unimplemented): Temporary function raised by the body of new
	subprograms below.
	(Leap_Sec_Ops): New package in the private part of Ada.Calendar. This
	unit provides handling of leap seconds and is used by the new Ada 2005
	packages Ada.Calendar.Arithmetic and Ada.Calendar.Formatting.
	(Split_W_Offset): Identical spec to that of Ada.Calendar.Split. This
	version returns an extra value which is the offset to UTC.

	* a-calend.adb (Split_W_Offset): Add call to localtime_tzoff.
	(Leap_Sec_Ops): New body for package in private part of Ada.Calendar.
	(Split_W_Offset): New function body.
	(Time_Of): When a date is close to UNIX epoch, compute the time for
	that date plus one day (that amount is later substracted after
	executing mktime) so there are no problems with time zone adjustments.

	* a-calend-mingw.adb: Remove Windows specific version no longer needed.

	* a-calari.ads, a-calari.adb, a-calfor.ads, a-calfor.adb,
	a-catizo.ads, a-catizo.adb: New files.

        * impunit.adb: Add new Ada 2005 entries

	* sysdep.c: Add external variable __gnat_invalid_tz_offset.
	Rename all occurences of "__gnat_localtime_r" to
	"__gnat_localtime_tzoff".
	(__gnat_localtime_tzoff for Windows): Add logic to retrieve the time
	zone data and calculate the GMT offset.
	(__gnat_localtime_tzoff for Darwin, Free BSD, Linux, Lynx and Tru64):
	Use the field "tm_gmtoff" to extract the GMT offset.
	(__gnat_localtime_tzoff for AIX, HPUX, SGI Irix and Sun Solaris): Use
	the external variable "timezone" to calculate the GMT offset.

From-SVN: r118234