[Ada] Add an annotation for static analysis

2019-07-10  Arnaud Charlet  <charlet@adacore.com>

gcc/ada/

	* sfn_scan.adb (Scan_SFN_Pragmas): Add pragma Assert.

From-SVN: r273342

gcc/ada/ChangeLog

+2019-07-10  Arnaud Charlet  <charlet@adacore.com>
+
+	* sfn_scan.adb (Scan_SFN_Pragmas): Add pragma Assert.
+
 2019-07-10  Hristian Kirtchev  <kirtchev@adacore.com>
 
 	* sem_ch3.adb (Check_Nonoverridable_Aspects): Correct the

gcc/ada/sfn_scan.adb

@@ -607,6 +607,7 @@ package body SFN_Scan is
 
    exception
       when others =>
+         pragma Assert (P'Valid);
          Cursor := P - S'First + 1;
          raise;
    end Scan_SFN_Pragmas;