private void referenceAdded(Reference ref) {
		Address addr = ref.getFromAddress();
		if (addr == Address.EXT_FROM_ADDRESS) {
			addr = null;
		}
		functionCacher.clearCache();
		program.setObjChanged(ProgramEvent.REFERENCE_ADDED, addr, ref, null, ref);
		if (ref.getReferenceType() == RefType.FALL_THROUGH) {
			program.getCodeManager().fallThroughChanged(ref.getFromAddress(), ref);
		}
	}
Removes the external entry point at the given address
@param addr that address at which to remove the external entry point attribute.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/references/ReferenceDBManager.java