* gimple.c (recalculate_side_effects) <tcc_constant>: New case.

From-SVN: r142541

gcc/ChangeLog

+2008-12-07  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gimple.c (recalculate_side_effects) <tcc_constant>: New case.
+
 2008-12-07  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/38405

gcc/gimple.c

@@ -3108,8 +3108,11 @@ recalculate_side_effects (tree t)
 	}
       break;
 
+    case tcc_constant:
+      /* No side-effects.  */
+      return;
+
     default:
-      /* Can never be used with non-expressions.  */
       gcc_unreachable ();
    }
 }

gcc/testsuite/ChangeLog

+2008-12-07  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/string_comparison.adb: New test.
+
 2008-12-07  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR tree-optimization/38405

gcc/testsuite/gnat.dg/string_comparison.adb

+-- { dg-do compile }
+
+with Ada.Text_IO; use Ada.Text_IO;
+
+procedure String_Comparison is
+   package Bool_IO is new Enumeration_IO (Boolean);
+   use Bool_IO;
+begin
+   Put (Boolean'Image (True) = "True");
+end;