[Ada] Silence useless -Wuninitialized warning

[Ada] Silence useless -Wuninitialized warning

[Eric Botcazou]

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This silences a warning issued for the call to the initialization procedure of 
a record type on a misaligned component of another record type.

Tested on x86_64-suse-linux, applied on the mainline and 9 branch.


2019-05-27  Eric Botcazou  <ebotcazou@adacore.com>

	* gcc-interface/trans.c (Call_to_gnu): Do not initialize the temporary
	created out of addressability concerns if it's for the _Init parameter
	of an initialization procedure.

-- 
Eric Botcazou

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Index: gcc-interface/trans.c
===================================================================
--- gcc-interface/trans.c	(revision 271658)
+++ gcc-interface/trans.c	(working copy)
@@ -5313,13 +5313,23 @@ Call_to_gnu (Node_Id gnat_node, tree *gn
 	  /* Create an explicit temporary holding the copy.  */
 	  if (atomic_p)
 	    gnu_name = build_atomic_load (gnu_name, sync);
-	  gnu_temp
-	    = create_init_temporary ("A", gnu_name, &gnu_stmt, gnat_actual);
 
-	  /* But initialize it on the fly like for an implicit temporary as
-	     we aren't necessarily having a statement list.  */
-	  gnu_name = build_compound_expr (TREE_TYPE (gnu_name), gnu_stmt,
-					  gnu_temp);
+	  /* Do not initialize it for the _Init parameter of an initialization
+	     procedure since no data is meant to be passed in.  */
+	  if (Ekind (gnat_formal) == E_Out_Parameter
+	      && Is_Entity_Name (Name (gnat_node))
+	      && Is_Init_Proc (Entity (Name (gnat_node))))
+	    gnu_name = gnu_temp = create_temporary ("A", TREE_TYPE (gnu_name));
+
+	  /* Initialize it on the fly like for an implicit temporary in the
+	     other cases, as we don't necessarily have a statement list.  */
+	  else
+	    {
+	      gnu_temp = create_init_temporary ("A", gnu_name, &gnu_stmt,
+						gnat_actual);
+	      gnu_name = build_compound_expr (TREE_TYPE (gnu_name), gnu_stmt,
+					      gnu_temp);
+	    }
 
 	  /* Set up to move the copy back to the original if needed.  */
 	  if (!in_param)