[C++ Patch] PR 44524

[Paolo Carlini]

Hi,

here submitter requests a more accurate error message for X.Y where X is 
a pointer to class type. Thus the below, tested x86_64-linux.

Ok for mainline?

Thanks,
Paolo.

//////////////////////////
/cp
2011-10-17  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/44524
        * typeck.c (build_class_member_access_expr): Provide a better error
        message for X.Y where X is a pointer to class type.
        (finish_class_member_access_expr): Likewise.

/testsuite
2011-10-17  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/44524
        * g++.dg/parse/error41.C: New.
        * g++.dg/parse/error20.C: Adjust.
Index: testsuite/g++.dg/parse/error20.C
===================================================================
--- testsuite/g++.dg/parse/error20.C    (revision 180087)
+++ testsuite/g++.dg/parse/error20.C    (working copy)
@@ -12,7 +12,7 @@ struct C {
 };
 int main() {
   C c;
-  A(c.p.i); // { dg-error "9:request for member 'i' in 'c.C::p', which is of 
non-class type 'B" }
+  A(c.p.i); // { dg-error "9:request for member 'i' in 'c.C::p', which has 
pointer type 'B" }
   return 0;
 }
 
Index: testsuite/g++.dg/parse/error41.C
===================================================================
--- testsuite/g++.dg/parse/error41.C    (revision 0)
+++ testsuite/g++.dg/parse/error41.C    (revision 0)
@@ -0,0 +1,11 @@
+// PR c++/44524
+
+template<typename, typename>
+struct map
+{
+  bool empty();
+};
+
+int bar(map<int, float> *X) {
+  return X.empty();  // { dg-error "which has pointer type 'map" }
+}
Index: cp/typeck.c
===================================================================
--- cp/typeck.c (revision 180087)
+++ cp/typeck.c (working copy)
@@ -2128,8 +2128,16 @@ build_class_member_access_expr (tree object, tree
   if (!CLASS_TYPE_P (object_type))
     {
       if (complain & tf_error)
-       error ("request for member %qD in %qE, which is of non-class type %qT",
-              member, object, object_type);
+       {
+         if (POINTER_TYPE_P (object_type)
+             && CLASS_TYPE_P (TREE_TYPE (object_type)))
+           error ("request for member %qD in %qE, which has pointer "
+                  "type %qT (maybe you meant to use %<->%> ?)",
+                  member, object, object_type);
+         else
+           error ("request for member %qD in %qE, which is of non-class "
+                  "type %qT", member, object, object_type);
+       }
       return error_mark_node;
     }
 
@@ -2508,8 +2516,16 @@ finish_class_member_access_expr (tree object, tree
   if (!CLASS_TYPE_P (object_type))
     {
       if (complain & tf_error)
-       error ("request for member %qD in %qE, which is of non-class type %qT",
-              name, object, object_type);
+       {
+         if (POINTER_TYPE_P (object_type)
+             && CLASS_TYPE_P (TREE_TYPE (object_type)))
+           error ("request for member %qD in %qE, which has pointer "
+                  "type %qT (maybe you meant to use %<->%> ?)",
+                  name, object, object_type);
+         else
+           error ("request for member %qD in %qE, which is of non-class "
+                  "type %qT", name, object, object_type);
+       }
       return error_mark_node;
     }