April 08, 2016
https://issues.dlang.org/show_bug.cgi?id=15897

          Issue ID: 15897
           Summary: private base functions not callable from base class
                    module without type change
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: rejects-valid
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: schveiguy@yahoo.com

Example (from
https://forum.dlang.org/post/jebqwhmasrtzrfhmlzeq@forum.dlang.org)

module a;
import b;

class Animal
{
    private void create() {}

}

void foo(Cat cat)
{
    cat.create(); // >> no property create for type 'b.cat'
}

void main() {}

--------------

module b;
import a;

class Cat: Animal {}

Compiles with 2.070

Fails in 2.071.0:

Error: no property 'create' for type 'b.Cat'

If I do this:

void foo(Cat cat)
{
    Animal a = cat;
    a.create();
}

It now compiles. The user shouldn't have to jump through this hoop, the compiler is aware of the access of create via the base class.

If you move Cat into the same module, it also compiles.

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