debug.adb: Add -gnatd.O to output SCO table

2009-07-15  Robert Dewar  <dewar@adacore.com>

	* debug.adb: Add -gnatd.O to output SCO table

	* lib-writ.adb (Write_Unit_Information): Use SCO_Output to output SCO
	information.

	* lib-writ.ads: Document addition of SCO lines to ALI file

	* par_sco.ads, par_sco.adb: New files.

	* opt.ads (Generate_SCO): New switch

	* par.adb (Par): Call SCO_Record to record SCO information

	* sem_warn.adb (Warn_On_Constant_Condition): Adjust SCO condition

	* switch-c.adb: Recognize -gnateS to generate SCO information

	* usage.adb: Add line for -gnateS

	* gcc-interface/Make-lang.in: Add dependency on par_sco.o for gnat1

From-SVN: r149669