a-textio.adb, [...]: Extensive changes to private part for wide character encoding

a-textio.adb, [...]: Extensive changes to private part for wide character encoding

2007-12-06  Robert Dewar  <dewar@adacore.com>

	* a-textio.adb, a-textio.ads:
	Extensive changes to private part for wide character encoding

	* a-witeio.ads, a-witeio.adb, a-ztexio.ads, a-ztexio.adb
	(Look_Ahead): Fix mishandling of encoded sequences
	Move declaration of Wch_Con to private part (should not be visible)

	* ali.adb (Scan_ALI): Set default encoding method to brackets instead of
	UTF-8. Probably this is never used, but if it is, brackets is
	clearly correct.

	* bindgen.adb (Get_WC_Encoding): New procedure to properly handle
	setting wide character encoding for no main program case and when
	encoding is specified using -W?
	Initialize stack limit of environment task if stack limit method of
	stack checking is enabled.
	(Gen_Adainit_Ada): Use Get_WC_Encoding to output encoding method
	(Gen_Adainit_C): Use Get_WC_Encoding to output encoding method
	(Get_Main_Unit_Name): New function.
	(Gen_Adainit_Ada): Add call to main program for .NET when needed.
	(Gen_Output_File): Set Bind_Main_Program to True for .NET

	* bindusg.adb: Add line for -Wx switch

	* s-wchcon.adb, s-wchcon.ads: (Is_Start_Of_Encoding): New function
	Add comments
	Add new useful constant WC_Longest_Sequences

	* switch-b.adb: Clean up handling of -Wx switch
	For -gnatWx, set Wide_Character_Encoding_Method_Specified

	* switch-c.adb: -gnatg activates warning on assertion errors
	For -gnatWx, set Wide_Character_Encoding_Method_Specified

	* s-wchcon.adb: (Is_Start_Of_Encoding): New function

From-SVN: r130817