This aligns the processing of constants used by reference in Identifier_to_gnu
with that of regular constants; in particular we stop returning the underlying
constant if this is the address of a constant and an lvalue is required.
Tested on i586-suse-linux, applied on the mainline.
2012-06-11 Eric Botcazou <ebotca...@adacore.com>
* gcc-interface/trans.c (Identifier_to_gnu): Test Is_Elementary_Type
instead of Is_Scalar_Type for a constant with an address clause.
Do not return the underlying constant for a constant used by reference
if it holds the address of a constant and an lvalue is required.
--
Eric Botcazou
Index: gcc-interface/trans.c
===================================================================
--- gcc-interface/trans.c (revision 188377)
+++ gcc-interface/trans.c (working copy)
@@ -1019,7 +1019,7 @@ Identifier_to_gnu (Node_Id gnat_node, tr
order-of-elaboration issue here. */
gnu_result_type = get_unpadded_type (gnat_temp_type);
- /* If this is a non-imported scalar constant with an address clause,
+ /* If this is a non-imported elementary constant with an address clause,
retrieve the value instead of a pointer to be dereferenced unless
an lvalue is required. This is generally more efficient and actually
required if this is a static expression because it might be used
@@ -1028,7 +1028,7 @@ Identifier_to_gnu (Node_Id gnat_node, tr
volatile-ness short-circuit here since Volatile constants must be
imported per C.6. */
if (Ekind (gnat_temp) == E_Constant
- && Is_Scalar_Type (gnat_temp_type)
+ && Is_Elementary_Type (gnat_temp_type)
&& !Is_Imported (gnat_temp)
&& Present (Address_Clause (gnat_temp)))
{
@@ -1080,7 +1080,10 @@ Identifier_to_gnu (Node_Id gnat_node, tr
= convert (build_pointer_type (gnu_result_type), gnu_result);
/* If it's a CONST_DECL, return the underlying constant like below. */
- else if (TREE_CODE (gnu_result) == CONST_DECL)
+ else if (TREE_CODE (gnu_result) == CONST_DECL
+ && !(DECL_CONST_ADDRESS_P (gnu_result)
+ && lvalue_required_p (gnat_node, gnu_result_type, true,
+ true, false)))
gnu_result = DECL_INITIAL (gnu_result);
/* If it's a renaming pointer and we are at the right binding level,
