limbo topvartype dereference of nil

[GoogleCodeExporter]

The error handlers in both /appl/cmd/limbo/types.b:/^topvartype and 
/limbo/types.c:/^topvartype dereference id.sym, which can be nil.

implement LimboTest;

Http: module {
    Url: adt {
        pick {
        Escaped =>
        Partial =>
        Unescaped =>
        }

        tostring:   fn(nil: self Url): string;
    };
};

LimboTest: module {
    init:   fn(nil: Http);
};

init(nil: Http) {}

Original issue reported on code.google.com by kristofwycz on 29 Jun 2014 at 12:51