protected NodeVisitor enterCall(Node n) throws SemanticException { if (n instanceof FieldDecl) { FieldDecl fd = (FieldDecl) n; FwdReferenceChecker frc = (FwdReferenceChecker) this.copy(); frc.inInitialization = true; frc.inStaticInit = fd.flags().flags().isStatic(); frc.declaredFields = new HashSet<FieldDef>(declaredFields); declaredFields.add(fd.fieldDef()); return frc; } else if (n instanceof Initializer) { FwdReferenceChecker frc = (FwdReferenceChecker) this.copy(); frc.inInitialization = true; frc.inStaticInit = ((Initializer) n).flags().flags().isStatic(); return frc; } else if (n instanceof FieldAssign) { FwdReferenceChecker frc = (FwdReferenceChecker) this.copy(); return frc; } else if (n instanceof Field) { if (inInitialization) { // we need to check if this is an illegal fwd reference. Field f = (Field) n; // an illegal fwd reference if a usage of an instance // (resp. static) field occurs in an instance (resp. static) // initialization, and the innermost enclosing class or // interface of the usage is the same as the container of // the field, and we have not yet seen the field declaration. // // In addition, if a field is not accessed as a simple name, // then all is ok ClassType currentClass = context().currentClass(); StructType fContainer = f.fieldInstance().container(); if (inStaticInit == f.fieldInstance().flags().isStatic() && currentClass.typeEquals(fContainer, context) && !declaredFields.contains(f.fieldInstance().def()) && f.isTargetImplicit()) { throw new SemanticException("Illegal forward reference", f.position()); } } } return this; }