re PR c++/22551 ([ICE] in tree_low_cst, at tree.c:3843)

.:	PR c++/22551
	* c-common.c (c_add_case_label): Clear LOW_VALUE and HIGH_VALUE's
	overflow flags.  Refactor some conditionals.
testsuite:
	PR c++/22551
	* g++.dg/other/switch2.C: New.

From-SVN: r105405

gcc/ChangeLog

+2005-10-14  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR c++/22551
+	* c-common.c (c_add_case_label): Clear LOW_VALUE and HIGH_VALUE's
+	overflow flags.  Refactor some conditionals.
+
 2005-10-13  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	PR tree-opt/21304

gcc/c-common.c

@@ -3588,25 +3588,32 @@ c_add_case_label (splay_tree cases, tree cond, tree orig_type,
     {
       low_value = check_case_value (low_value);
       low_value = convert_and_check (type, low_value);
+      if (low_value == error_mark_node)
+	goto error_out;
+      /* Do not propagate any overflow information past this point.
+	 It is safe to just clear the flags, as any constants with
+	 them set will not be shared.  */
+      TREE_CONSTANT_OVERFLOW (low_value) = TREE_OVERFLOW (low_value) = 0;
     }
   if (high_value)
     {
       high_value = check_case_value (high_value);
       high_value = convert_and_check (type, high_value);
+      if (high_value == error_mark_node)
+	goto error_out;
+      TREE_CONSTANT_OVERFLOW (high_value) = TREE_OVERFLOW (high_value) = 0;
     }
 
-  /* If an error has occurred, bail out now.  */
-  if (low_value == error_mark_node || high_value == error_mark_node)
-    goto error_out;
-
-  /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
-     really a case range, even though it was written that way.  Remove
-     the HIGH_VALUE to simplify later processing.  */
-  if (tree_int_cst_equal (low_value, high_value))
-    high_value = NULL_TREE;
-  if (low_value && high_value
-      && !tree_int_cst_lt (low_value, high_value))
-    warning (0, "empty range specified");
+  if (low_value && high_value)
+    {
+      /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
+         really a case range, even though it was written that way.
+         Remove the HIGH_VALUE to simplify later processing.  */
+      if (tree_int_cst_equal (low_value, high_value))
+	high_value = NULL_TREE;
+      else if (!tree_int_cst_lt (low_value, high_value))
+	warning (0, "empty range specified");
+    }
 
   /* See if the case is in range of the type of the original testing
      expression.  If both low_value and high_value are out of range,

gcc/testsuite/ChangeLog

 2005-10-14  Nathan Sidwell  <nathan@codesourcery.com>
 
+	PR c++/22551
+	* g++.dg/other/switch2.C: New.
+
 	PR c++/23984
 	* g++.dg/init/ctor7.C: New.
 

gcc/testsuite/g++.dg/other/switch2.C

+// Copyright (C) 2005 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 13 Oct 2005 <nathan@codesourcery.com>
+
+// PR 22551:ICE
+// Origin:  Johnny Casey <emailwastefilter-bugzillagccorg@yahoo.com>
+
+const int B = 0x80000000;
+
+#define b(x) (B + x)
+
+
+int Foo (int error)
+{
+  switch (error)
+  {
+  case b (1): return 0; // { dg-error "overflow" "" }
+  case b (2): return 0; // { dg-error "overflow" "" }
+  case b (3): return 0; // { dg-error "overflow" "" }
+  case b (4): return 0; // { dg-error "overflow" "" }
+  case b (5): return 0; // { dg-error "overflow" "" }
+ }
+}