trans.c (lvalue_required_p): Deal with character and enumeration literals as index values.

	* gcc-interface/trans.c (lvalue_required_p) <N_Indexed_Component>: Deal
	with character and enumeration literals as index values.

From-SVN: r223913

gcc/ada/ChangeLog

 2015-06-01  Eric Botcazou  <ebotcazou@adacore.com>
 
+	* gcc-interface/trans.c (lvalue_required_p) <N_Indexed_Component>: Deal
+	with character and enumeration literals as index values.
+
+2015-06-01  Eric Botcazou  <ebotcazou@adacore.com>
+
 	* gcc-interface/gigi.h (build_simple_component_ref): Declare.
 	* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Variable>: Deal with
 	address clause on aliased object with unconstrained nominal subtype.

gcc/ada/gcc-interface/trans.c

@@ -858,14 +858,17 @@ lvalue_required_p (Node_Id gnat_node, tree gnu_type, bool constant,
       if (Prefix (gnat_parent) != gnat_node)
 	return 0;
 
-      /* ??? Consider that referencing an indexed component with a
-	 non-constant index forces the whole aggregate to memory.
-	 Note that N_Integer_Literal is conservative, any static
-	 expression in the RM sense could probably be accepted.  */
+      /* ??? Consider that referencing an indexed component with a variable
+	 index forces the whole aggregate to memory.  Note that testing only
+	 for literals is conservative, any static expression in the RM sense
+	 could probably be accepted with some additional work.  */
       for (gnat_temp = First (Expressions (gnat_parent));
 	   Present (gnat_temp);
 	   gnat_temp = Next (gnat_temp))
-	if (Nkind (gnat_temp) != N_Integer_Literal)
+	if (Nkind (gnat_temp) != N_Character_Literal
+	    && Nkind (gnat_temp) != N_Integer_Literal
+	    && !(Is_Entity_Name (gnat_temp)
+		 && Ekind (Entity (gnat_temp)) == E_Enumeration_Literal))
 	  return 1;
 
       /* ... fall through ... */