No error reported for missing equation for NTA child component

[Jesper Öqvist]

Declaring an NTA child in the abstract grammar does not cause JastAdd to report an error if a corresponding equation for the NTA child is missing. This can cause problems when the NTA child was a non-NTA in a supertype. The following example from ExtendJ illustrates the problem:

abstract TypeDecl ::= ... BodyDecl*;

PrimitiveType : TypeDecl ::= ... /BodyDecl*/;

This compiles fine even if there is no equation PrimitiveType.getBodyDeclList(). Problems occur during runtime when trying to access the BodyDecl list in a PrimitiveType node, because then the getBodyDeclList() method inherited from TypeDecl is called and it either accesses the wrong node or returns null.