[Ada] Do not set a bogus Esize on subtype built for Component_Size clause

2019-12-16  Eric Botcazou  <ebotcazou@adacore.com>

gcc/ada/

	* sem_ch13.adb (Analyze_Attribute_Definition_Clause): Set only
	the RM_Size on the subtype built for a Component_Size clause
	when the component type is a biased integer type.

From-SVN: r279437

gcc/ada/ChangeLog

+2019-12-16  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* sem_ch13.adb (Analyze_Attribute_Definition_Clause): Set only
+	the RM_Size on the subtype built for a Component_Size clause
+	when the component type is a biased integer type.
+
 2019-12-16  Arnaud Charlet  <charlet@adacore.com>
 
 	* socket.c: Shutdown warning.

gcc/ada/sem_ch13.adb

@@ -5476,7 +5476,7 @@ package body Sem_Ch13 is
                   Analyze (Decl, Suppress => All_Checks);
 
                   Set_Has_Delayed_Freeze        (New_Ctyp, False);
-                  Set_Esize                     (New_Ctyp, Csize);
+                  Init_Esize                    (New_Ctyp);
                   Set_RM_Size                   (New_Ctyp, Csize);
                   Init_Alignment                (New_Ctyp);
                   Set_Is_Itype                  (New_Ctyp, True);