re PR c++/10891 (code using dynamic_cast causes segfaults when -fno-rtti is used)

2006-01-22  Gabriel Dos Reis  <gdr@integrable-solutions.net>

        PR c++/10891
        * rtti.c (build_dynamic_cast): Reject dynamic_cast use if
        -fno-rtti.

testsuite/
2006-01-22  Gabriel Dos Reis  <gdr@integrable-solutions.net>

        PR c++/10891
        * g++.dg/rtti/no-rtti.C: New.

From-SVN: r110092

gcc/cp/ChangeLog

+2006-01-22  Gabriel Dos Reis  <gdr@integrable-solutions.net>
+
+	PR c++/10891
+	* rtti.c (build_dynamic_cast): Reject dynamic_cast use if
+	-fno-rtti. 
+
 2006-01-21  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/25895

gcc/cp/rtti.c

@@ -699,6 +699,14 @@ build_dynamic_cast (tree type, tree expr)
   if (type == error_mark_node || expr == error_mark_node)
     return error_mark_node;
 
+  /* Use of dynamic_cast when -fno-rtti is a disaster waiting to happen.
+     See PR C++/10891.  Reject.  */
+  if (!flag_rtti)
+    {
+      error ("%<dynamic_cast%> not permitted with -fno-rtti");
+      return error_mark_node;
+    }
+
   if (processing_template_decl)
     {
       expr = build_min (DYNAMIC_CAST_EXPR, type, expr);

gcc/testsuite/ChangeLog

+2006-01-22  Gabriel Dos Reis  <gdr@integrable-solutions.net>
+
+	PR c++/10891
+	* g++.dg/rtti/no-rtti.C: New.
+
 2006-01-21  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/25895

gcc/testsuite/g++.dg/rtti/no-rtti.C

+// { dg-do compile }
+// { dg-options "-fno-rtti" }
+
+// PR C++/10891
+
+struct A {
+   virtual ~A() { }
+};
+
+struct B : A {
+};
+
+A* f();
+
+int main()
+{
+   B* b = dynamic_cast<B*>(f()); // { dg-error "error: " }
+}