Cannot access private template argument

[dlangBugzillaToGithub]

Victor Porton (@vporton) reported this on 2019-01-01T14:18:04Z

Transferred from https://issues.dlang.org/show_bug.cgi?id=19536

Description

Originally appeared in https://stackoverflow.com/q/53982974/856090

//handled_record.d:

module handled_record;

template CObjects(alias destructor) {
    void f() {
        destructor();
    }
}

//world.d:

module world;

import handled_record;

private void free() { }

alias objects = CObjects!(free);

Compiling:

$ dmd -c *.d
handled_record.d(5): Error: function world.free is not accessible from module handled_record
world.d(7): Error: template instance `handled_record.CObjects!(free)` error instantiating

The error disappears if I remove private keyword.

Is it a compiler bug? (In my understanding the alias symbol passed to a template should be accessible by the template because it is explicitly passed to the template, even if it is private.)