2008-05-20  Kevin Pouget  <pouget@adacore.com>

	* exp_smem.ads, exp_smem.adb: Construction of access and assign
	routines has been replaced by an instantiation of
	System.Shared_Storage.Shared_Var_Procs generic package, while expanding
	shared variable declaration.
	Calls to access and assign routines have been replaced by calls to
	Read/Write routines of System.Shared_Storage.Shared_Var_Procs
	instantiated package.
	
	* rtsfind.ads: RE_Shared_Var_Procs entry has been added in RE_Unit_Table
	It identifies the new generic package added in s-shasto.

	* s-shasto.adb, s-shasto.ads: A new generic package has been added, it
	is instantiated for each shared passive variable. It provides
	supporting procedures called upon each read or write access by the
	expanded code.

	* sem_attr.adb:
	For this runtime unit (always compiled in GNAT mode), we allow
	stream attributes references for limited types for the case where
	shared passive objects are implemented using stream attributes,
	which is the default in GNAT's persistent storage implementation.

From-SVN: r135627