A counter-example for “a simpler construction for showing the intrinsically exponential complexity of the circularity problem for attribute grammars”

Jazayeri [J. ACM 28, 4 (Oct. 1981), 715-720] proposes a simpler construction for use in the proof by Jazayeri et al. [Commun. ACM 18, 12 (Dec. 1975), 697-706] that the circularity problem for attribute grammars has inherent exponential time complexity. The simplification introduces a flaw that invalidates the proof. The flaw can be corrected, at the cost of eliminating some of the simplification claimed for the new construction.