re PR c++/20186 (ICE with static_cast and type dependent variable (templates))

cp:
	PR c++/20186
	* pt.c (contains_dependent_cast_p): New.
	(fold_non_dependent_expr): Call it.
testsuite:
	PR c++/20186
	* g++.dg/template/non-dependent12.C: New.

From-SVN: r96190

gcc/cp/ChangeLog

+2005-03-08  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR c++/20186
+	* pt.c (contains_dependent_cast_p): New.
+	(fold_non_dependent_expr): Call it.
+
 2005-03-08  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/20142

gcc/cp/pt.c

@@ -3258,6 +3258,52 @@ redeclare_class_template (tree type, tree parms)
     }
 }
 
+/* Return true if non-dependent expressions EXPR contains within it a
+   cast expression with a dependent argument.  */
+
+static bool
+contains_dependent_cast_p (tree expr)
+{
+  switch (TREE_CODE (expr))
+    {
+    case CAST_EXPR:
+    case REINTERPRET_CAST_EXPR:
+    case STATIC_CAST_EXPR:
+    case DYNAMIC_CAST_EXPR:
+    case CONST_CAST_EXPR:
+      {
+	tree op = TREE_OPERAND (expr, 0);
+
+	if (op && (type_dependent_expression_p (op)
+		   || value_dependent_expression_p (op)))
+	  return true;
+      }
+      break;
+
+    case TREE_LIST:
+      /* The operands of a CALL_EXPR are held as a list.  */
+      for (; expr; expr = TREE_CHAIN (expr))
+	if (contains_dependent_cast_p (TREE_VALUE (expr)))
+	  return true;
+      return false;
+
+    default:
+      break;
+    }
+
+  if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expr))))
+    {
+      int ix;
+  
+      for (ix = TREE_CODE_LENGTH (TREE_CODE (expr)); ix--;)
+	if (TREE_OPERAND (expr, ix)
+	    && contains_dependent_cast_p (TREE_OPERAND (expr, ix)))
+	  return true;
+    }
+  
+  return false;
+}
+
 /* Simplify EXPR if it is a non-dependent expression.  Returns the
    (possibly simplified) expression.  */
 
@@ -3273,7 +3319,8 @@ fold_non_dependent_expr (tree expr)
      as two declarations of the same function, for example.  */
   if (processing_template_decl
       && !type_dependent_expression_p (expr)
-      && !value_dependent_expression_p (expr))
+      && !value_dependent_expression_p (expr)
+      && !contains_dependent_cast_p (expr))
     {
       HOST_WIDE_INT saved_processing_template_decl;
 

gcc/testsuite/ChangeLog

+2005-03-09  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR c++/20186
+	* g++.dg/template/non-dependent12.C: New.
+
 2005-03-08  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/20142

gcc/testsuite/g++.dg/template/non-dependent12.C

+// Copyright (C) 2005 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 8 Mar 2005 <nathan@codesourcery.com>
+
+// PR 20186: ICE
+// Origin: Jan Dvorak <jan.dvorak@kraxnet.cz>
+
+template<typename T> void foo(T &t)
+{
+  int i = static_cast<int>(t);
+}