method.c (do_build_assign_ref): Construct appropriately CV-qualified base reference.

cp:
	* method.c (do_build_assign_ref): Construct appropriately
	CV-qualified base reference. Don't allow const casts in base
	conversion.
testsuite:
	* g++.old-deja/g++.other/op2.C: New test.

From-SVN: r37893

gcc/cp/ChangeLog

 2000-11-30  Nathan Sidwell  <nathan@codesourcery.com>
 
+	* method.c (do_build_assign_ref): Construct appropriately
+	CV-qualified base reference. Don't allow const casts in base
+	conversion.
+
+2000-11-30  Nathan Sidwell  <nathan@codesourcery.com>
+
 	* call.c (build_over_call): Use VOID_TYPE_P. Don't die on
 	incomplete return type.
 

gcc/cp/method.c

@@ -2428,9 +2428,12 @@ do_build_assign_ref (fndecl)
       for (i = 0; i < n_bases; ++i)
 	{
 	  tree basetype = BINFO_TYPE (TREE_VEC_ELT (binfos, i));
-	  tree p = convert_to_reference
-	    (build_reference_type (basetype), parm,
-	     CONV_IMPLICIT|CONV_CONST, LOOKUP_COMPLAIN, NULL_TREE);
+	  tree p = build_qualified_type
+	      (basetype, CP_TYPE_QUALS (TREE_TYPE (parm)));
+
+	  p = convert_to_reference
+	    (build_reference_type (p), parm,
+	     CONV_IMPLICIT, LOOKUP_COMPLAIN, NULL_TREE);
 	  p = convert_from_reference (p);
 	  p = build_member_call (basetype, ansi_assopname (NOP_EXPR),
 				 build_tree_list (NULL_TREE, p));

gcc/testsuite/ChangeLog

 2000-11-30  Nathan Sidwell  <nathan@codesourcery.com>
 
+	* g++.old-deja/g++.other/op2.C: New test.
+
+2000-11-30  Nathan Sidwell  <nathan@codesourcery.com>
+
 	* g++.old-deja/g++.other/crash38.C: New test.
 
 2000-11-29  Toon Moene  <toon@moene.indiv.nluug.nl>

gcc/testsuite/g++.old-deja/g++.other/op2.C

+// Copyright (C) 2000 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 28 Nov 2000 <nathan@codesourcery.com>
+
+// Bug 91. We'd not preserve constness looking for a base classes assignment
+// operator.
+
+#include <stdio.h>
+
+int glob = 0;
+
+struct A
+{
+  A() {}
+
+  A( A& arg) 
+  { printf ("%s\n", __PRETTY_FUNCTION__); glob = 1;}
+
+  A( const A& arg)
+  { printf ("%s\n", __PRETTY_FUNCTION__); glob = 2;}
+
+  A& operator=( A& ) 
+  { printf ("%s\n", __PRETTY_FUNCTION__); glob = 3; return *this; }
+
+  A& operator=( const A& ) 
+  { printf ("%s\n", __PRETTY_FUNCTION__); glob = 4; return *this; }
+};
+
+struct B : A
+{
+  B () {}
+};
+
+void foo( A& )
+{
+  printf ("%s\n", __PRETTY_FUNCTION__); glob = 5;
+}
+
+void foo( const A& )
+{
+ printf ("%s\n", __PRETTY_FUNCTION__); glob = 6;
+}
+
+
+int main()
+{
+  const A a0;
+  glob = 0; printf ("A(cA) : ");  A a1(a0); if (glob != 2) return 1;
+  glob = 0; printf ("A(A ) : ");  A a2(a1); if (glob != 1) return 2;
+  
+  const B b0;
+  glob = 0; printf ("B(cB) : ");  B b1(b0); if (glob != 2) return 3;
+  glob = 0; printf ("B(B ) : ");  B b2(b1); if (glob != 2) return 4;
+
+  glob = 0; printf ("A= cA : ");  a1 = a0; if (glob != 4) return 5;
+  glob = 0; printf ("A= A : ");   a1 = a2; if (glob != 3) return 6;
+  glob = 0; printf ("B= cB : ");  b1 = b0; if (glob != 4) return 7;
+  glob = 0; printf ("B= B : ");   b1 = b2; if (glob != 4) return 8;
+
+  glob = 0; printf ("foo(cB): "); foo(b0); if (glob != 6) return 9;
+  glob = 0; printf ("foo(B ): "); foo(b2); if (glob != 5) return 10;
+
+  return 0;
+}