ada: Fix false positive error for classwide containers

Get_Cursor_Type fails if a classwide container type
is passed to it as it cannot correctly identify the
cursor type since it is expecting the iteration functions
to have a container argument with a classwide container type.

gcc/ada/ChangeLog:

	* sem_util.adb (Get_Cursor_Type): use the
	specific type for classwide container checks.

1 files changed, 8 insertions, 2 deletions

diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 123c79d..e4dd8db 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -10399,6 +10399,7 @@ package body Sem_Util is
       Func     : Entity_Id;
       First_Op : Entity_Id;
       Cursor   : Entity_Id;
+      Specific_Type : Entity_Id := Typ;
 
    begin
       --  If error already detected, return
@@ -10407,6 +10408,10 @@ package body Sem_Util is
          return Any_Type;
       end if;
 
+      if Is_Class_Wide_Type (Specific_Type) then
+         Specific_Type := Etype (Typ);
+      end if;
+
       --  The cursor type for an Iterable aspect is the return type of a
       --  non-overloaded First primitive operation. Locate association for
       --  First.
@@ -10437,12 +10442,13 @@ package body Sem_Util is
       --  is created for it, check that the base type of the first formal
       --  of First matches the base type of the domain.
 
-      Func := First_Entity (Scope (Typ));
+      Func := First_Entity (Scope (Specific_Type));
       while Present (Func) loop
          if Chars (Func) = Chars (First_Op)
            and then Ekind (Func) = E_Function
            and then Present (First_Formal (Func))
-           and then Base_Type (Etype (First_Formal (Func))) = Base_Type (Typ)
+           and then Base_Type (Etype (First_Formal (Func)))
+                    = Base_Type (Specific_Type)
            and then No (Next_Formal (First_Formal (Func)))
          then
             if Cursor /= Any_Type then