2007-09-26  Hristian Kirtchev  <kirtchev@adacore.com>

	* sem_ch8.adb (Analyze_Use_Type): Code cleanup.
	(Applicable_Use): Emit a warning when a package tries to use itself.
	(Use_One_Type): Add variable Is_Known_Used. Emit a warning when a type
	is already in use or the package where it is declared is in use or is
	declared in the current package.
	(Spec_Reloaded_For_Body): New subsidiary routine for Use_One_Type.

	* a-tasatt.adb, s-osprim-vxworks.adb, g-socthi-mingw.adb,
	s-intman-vms.adb, g-socket.adb, g-thread.adb, s-tarest.adb,
	s-tassta.adb, s-tporft.adb: Remove redundant 'use type' clause.

From-SVN: r128779