sem_attr.adb (Analyze_Attribute): Defend against bad Val attribute.

	* sem_attr.adb (Analyze_Attribute): Defend against bad Val attribute.
	Fixes compilation abandoned bomb in B24009B.

From-SVN: r47683

gcc/ada/ChangeLog

+2001-12-05  Robert Dewar <dewar@gnat.com>
+
+	* sem_attr.adb (Analyze_Attribute): Defend against bad Val attribute. 
+	Fixes compilation abandoned bomb in B24009B.
+
 2001-12-05  Ed Schonberg <schonber@gnat.com>
 
 	* sem_ch12.adb:

gcc/ada/sem_attr.adb

@@ -1476,7 +1476,9 @@ package body Sem_Attr is
          E1 := First (Exprs);
          Analyze (E1);
 
-         if Etype (E1) = Any_Type then
+         --  Check for missing or bad expression (result of previous error)
+
+         if No (E1) or else Etype (E1) = Any_Type then
             raise Bad_Attribute;
          end if;