Tested on x86_64-suse-linux, applied on the mainline.
2017-05-15 Eric Botcazou <ebotca...@adacore.com>
* gcc-interface/trans.c (return_value_ok_for_nrv_p): Only apply the
addressability check in the constrained case.
--
Eric BotcazouIndex: gcc-interface/trans.c
===================================================================
--- gcc-interface/trans.c (revision 248052)
+++ gcc-interface/trans.c (working copy)
@@ -3238,8 +3238,9 @@ Loop_Statement_to_gnu (Node_Id gnat_node
RETURN_EXPR [<retval> = Ri]
[...]
- and we try to fulfill a simple criterion that would make it possible to
- replace one or several Ri variables with the RESULT_DECL of the function.
+ where the Ri are not addressable and we try to fulfill a simple criterion
+ that would make it possible to replace one or several Ri variables by the
+ single RESULT_DECL of the function.
The first observation is that RETURN_EXPRs that don't directly reference
any of the Ri variables on the RHS of their assignment are transparent wrt
@@ -3271,8 +3272,8 @@ Loop_Statement_to_gnu (Node_Id gnat_node
because the anonymous return object is allocated on the secondary stack
and RESULT_DECL is only a pointer to it. Each return object can be of a
different size and is allocated separately so we need not care about the
- aforementioned overlapping issues. Therefore, we don't collect the other
- expressions and skip step #2 in the algorithm. */
+ addressability and the aforementioned overlapping issues. Therefore, we
+ don't collect the other expressions and skip step #2 in the algorithm. */
struct nrv_data
{
@@ -3612,7 +3613,8 @@ return_value_ok_for_nrv_p (tree ret_obj,
if (TREE_STATIC (ret_val))
return false;
- if (TREE_ADDRESSABLE (ret_val))
+ /* For the constrained case, test for addressability. */
+ if (ret_obj && TREE_ADDRESSABLE (ret_val))
return false;
/* For the constrained case, test for overalignment. */
