Politico says that:
four crucial provisions of the main EU treaty clash with - and should not prevail - over the Polish constitution.
Article 1 that sets up the EU as an 'ever closer union'
Article 2 that sets up the EU values on "human dignity, freedom, equality, rule of law, democracy and respect for minorities."
Article 4.3 that sets up the principle of "sincere cooperation" between EU members
Article 19 that sets up the Court of Justice for the EU (CJEU) and which interprets, implements and ensures observation of EU law