re PR c++/14199 (Unjustified warning about unused variable)

	PR c++/14199
	* pt.c (tsubst_copy): Call mark_used for a PARM_DECL.

	PR c++/14173
	* semantics.c (begin_class_definition): Set TYPE_PACKED correctly
	for all type variants.

	PR c++/14173
	* g++.dg/ext/packed5.C: New test.

	PR c++/14199
	* g++.dg/warn/Wunused-5.C: New test.

	PR c++/13927
	* decl.c (duplicate_decls): Return error_mark_node for invalid
	redeclarations.
	* name-lookup.c (push_namespace): Ignore the return value from
	pushdecl.
	* pt.c (push_template_decl_real): Robustify.

	PR c++/13927
	* g++.dg/other/error8.C: Remove XFAIL markers.

From-SVN: r78159

5 files changed, 32 insertions, 6 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index d1dea6d..e3f51e9 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,21 @@
+2004-02-20  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/14199
+	* pt.c (tsubst_copy): Call mark_used for a PARM_DECL.
+
+	PR c++/14173
+	* semantics.c (begin_class_definition): Set TYPE_PACKED correctly
+	for all type variants.
+
 2004-02-19  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/13927
+	* decl.c (duplicate_decls): Return error_mark_node for invalid
+	redeclarations.
+	* name-lookup.c (push_namespace): Ignore the return value from
+	pushdecl.
+	* pt.c (push_template_decl_real): Robustify.
+
 	PR c++/14186
 	* name-lookup.c (push_class_level_binding): Do not complain about
 	adding a binding for a member whose name is the same as the
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index f3821c3..1db274e 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -1319,10 +1319,7 @@ duplicate_decls (tree newdecl, tree olddecl)
 	olddecl = TREE_VALUE (olddecl);
       cp_error_at ("previous declaration of `%#D'", olddecl);
 
-      /* New decl is completely inconsistent with the old one =>
-	 tell caller to replace the old one.  */
-
-      return NULL_TREE;
+      return error_mark_node;
     }
   else if (!types_match)
     {
diff --git a/gcc/cp/name-lookup.c b/gcc/cp/name-lookup.c
index e823ae3..be1b822 100644
--- a/gcc/cp/name-lookup.c
+++ b/gcc/cp/name-lookup.c
@@ -3080,7 +3080,7 @@ push_namespace (tree name)
       /* Make a new namespace, binding the name to it.  */
       d = build_lang_decl (NAMESPACE_DECL, name, void_type_node);
       DECL_CONTEXT (d) = FROB_CONTEXT (current_namespace);
-      d = pushdecl (d);
+      pushdecl (d);
       if (anon)
 	{
 	  /* Clear DECL_NAME for the benefit of debugging back ends.  */
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 779347b..1f97a53 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -2774,6 +2774,9 @@ push_template_decl_real (tree decl, int is_friend)
   int is_partial;
   int new_template_p = 0;
 
+  if (decl == error_mark_node)
+    return decl;
+
   /* See if this is a partial specialization.  */
   is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
 		&& TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
@@ -7381,6 +7384,7 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
     case PARM_DECL:
       r = retrieve_local_specialization (t);
       my_friendly_assert (r != NULL, 20020903);
+      mark_used (r);
       return r;
 
     case CONST_DECL:
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 511c7bc..b7a7f4a 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -2042,7 +2042,16 @@ begin_class_definition (tree t)
   maybe_process_partial_specialization (t);
   pushclass (t);
   TYPE_BEING_DEFINED (t) = 1;
-  TYPE_PACKED (t) = flag_pack_struct;
+  if (flag_pack_struct)
+    {
+      tree v;
+      TYPE_PACKED (t) = 1;
+      /* Even though the type is being defined for the first time
+	 here, there might have been a forward declaration, so there
+	 might be cv-qualified variants of T.  */
+      for (v = TYPE_NEXT_VARIANT (t); v; v = TYPE_NEXT_VARIANT (v))
+	TYPE_PACKED (v) = 1;
+    }
   /* Reset the interface data, at the earliest possible
      moment, as it might have been set via a class foo;
      before.  */