<p>追記</p>
<p>AZ-Prolog Version 9.63 (Linux/x64) GCC 5.4.0<br />
Copyright (C) SOFNEC CO., LTD. 1987-2017/06/29<br />
?-a(X)=X,a(Y)=Y, X == Y.<br />
Too complex term</p>
<p>?-a(X)=Y,a(Y)=X, X == Y.<br />
Too complex term</p>
<p>?-a(X)=X,a(Y)=Y, X = Y.<br />
Segmentation fault (コアダンプ)</p>
<p>?-a(X)=Y,a(Y)=X, X = Y.<br />
Segmentation fault (コアダンプ)</p>