https://issues.dlang.org/show_bug.cgi?id=20576

          Issue ID: 20576
           Summary: TemplateTypeParameter default values are not checked
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: accepts-invalid
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: b2.temp@gmx.com

The following code should not compile

---
void foo(T : Object = INVALID)(T t)
{

}

void main()
{
    foo(null);
}
---

because INVALID does not give a valid symbol, although it is not used in the call.

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