re PR c++/33101 ([DR 577] allow typedefs for void in empty parameter list)

/cp
2014-06-14  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/33101
	* decl.c (grokparms): Improve error message about void parameters.
	* error.c (type_to_string): Fix aka cut off code.

/testsuite
2014-06-14  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/33101
	* g++.dg/other/void3.C: New.
	* g++.dg/conversion/err-recover1.C: Update.

From-SVN: r211673

gcc/cp/ChangeLog

+2014-06-14  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/33101
+	* decl.c (grokparms): Improve error message about void parameters.
+	* error.c (type_to_string): Fix aka cut off code.
+
 2014-06-12  Jason Merrill  <jason@redhat.com>
 
 	* call.c (convert_arg_to_ellipsis): Use abi_version_crosses.

gcc/cp/decl.c

@@ -11137,12 +11137,24 @@ grokparms (tree parmlist, tree *parms)
       type = TREE_TYPE (decl);
       if (VOID_TYPE_P (type))
 	{
-	  if (same_type_p (type, void_type_node)
-	      && DECL_SELF_REFERENCE_P (type)
-	      && !DECL_NAME (decl) && !result && TREE_CHAIN (parm) == void_list_node)
+	  if (type == void_type_node
+	      && !init
+	      && !DECL_NAME (decl) && !result
+	      && TREE_CHAIN (parm) == void_list_node)
 	    /* this is a parmlist of `(void)', which is ok.  */
 	    break;
-	  cxx_incomplete_type_error (decl, type);
+	  else if (typedef_variant_p (type))
+	    error_at (DECL_SOURCE_LOCATION (decl),
+		      "invalid use of typedef-name %qT in "
+		      "parameter declaration", type);
+	  else if (cv_qualified_p (type))
+	    error_at (DECL_SOURCE_LOCATION (decl),
+		      "invalid use of cv-qualified type %qT in "
+		      "parameter declaration", type);
+	  else
+	    error_at (DECL_SOURCE_LOCATION (decl),
+		      "invalid use of type %<void%> in parameter "
+		      "declaration");
 	  /* It's not a good idea to actually create parameters of
 	     type `void'; other parts of the compiler assume that a
 	     void type terminates the parameter list.  */

gcc/cp/error.c

@@ -2922,7 +2922,7 @@ type_to_string (tree typ, int verbose)
   if (typ && TYPE_P (typ) && typ != TYPE_CANONICAL (typ)
       && !uses_template_parms (typ))
     {
-      int aka_start; char *p;
+      int aka_start, aka_len; char *p;
       struct obstack *ob = pp_buffer (cxx_pp)->obstack;
       /* Remember the end of the initial dump.  */
       int len = obstack_object_size (ob);
@@ -2932,10 +2932,11 @@ type_to_string (tree typ, int verbose)
       /* And remember the start of the aka dump.  */
       aka_start = obstack_object_size (ob);
       dump_type (cxx_pp, aka, flags);
+      aka_len = obstack_object_size (ob) - aka_start;
       pp_right_brace (cxx_pp);
       p = (char*)obstack_base (ob);
       /* If they are identical, cut off the aka with a NUL.  */
-      if (memcmp (p, p+aka_start, len) == 0)
+      if (len == aka_len && memcmp (p, p+aka_start, len) == 0)
 	p[len] = '\0';
     }
   return pp_ggc_formatted_text (cxx_pp);

gcc/testsuite/ChangeLog

+2014-06-14  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/33101
+	* g++.dg/other/void3.C: New.
+	* g++.dg/conversion/err-recover1.C: Update.
+
 2014-06-13  Peter Bergner  <bergner@vnet.ibm.com>
 
 	PR target/61415

gcc/testsuite/g++.dg/conversion/err-recover1.C

 // PR c++/42219
 
-void foo(const void);		// { dg-error "incomplete|const" }
+void foo(const void);		// { dg-error "invalid use of cv-qualified" }
 
 void bar()
 {

gcc/testsuite/g++.dg/other/void3.C

+// PR c++/33101
+
+typedef void v;
+typedef v (*pf)(v);  // { dg-error "invalid use of typedef-name" }