re PR target/43708 (gcc.dg/pragma-darwin.c "set not used", not working with pragma)

	PR target/43708
	* config/darwin-c.c (darwin_pragma_unused): Set DECL_READ_P
	in addition to TREE_USED, to avoid "set but unused" warnings.

From-SVN: r159164

gcc/ChangeLog

+2010-05-07  Iain Sandoe <iains@gcc.gnu.org>
+
+	PR target/43708
+	* config/darwin-c.c (darwin_pragma_unused): Set DECL_READ_P
+	in addition to TREE_USED, to avoid "set but unused" warnings.
+
 2010-05-07  Changpeng Fang  <changpeng.fang@amd.com>
 
 	* tree-ssa-loop-prefetch.c (TRIP_COUNT_TO_AHEAD_RATIO): New.

gcc/config/darwin-c.c

@@ -144,7 +144,10 @@ darwin_pragma_unused (cpp_reader *pfile ATTRIBUTE_UNUSED)
 	  tree local = lookup_name (decl);
 	  if (local && (TREE_CODE (local) == PARM_DECL
 			|| TREE_CODE (local) == VAR_DECL))
-	    TREE_USED (local) = 1;
+	    {
+	      TREE_USED (local) = 1;
+	      DECL_READ_P (local) = 1;
+	    }
 	  tok = pragma_lex (&x);
 	  if (tok != CPP_COMMA)
 	    break;