@Override
	public ReferenceIterator getReferencesTo(Address addr) {
		lock.acquire();
		try {
			if (addr.isStackAddress() || addr.isRegisterAddress()) {
				throw new UnsupportedOperationException(
					"getReferencesTo not supported for stack/register addresses");
			}
			RefList toRefs = getToRefs(addr);
			if (toRefs != null) {
				return toRefs.getRefs();
			}
		}
		catch (IOException e) {
			program.dbError(e);
		}
		finally {
			lock.release();
		}
		return new EmptyMemReferenceIterator();
	}
Symbol has been added
@param sym new symbol
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/references/ReferenceDBManager.java