#61 Spurious threat in reflex stipulations

[Thomas Maeder]

Since version 4.37 (probably earlier), Popeye has given a spurious threat in the following problem:

+---a---b---c---d---e---f---g---h---+
| |
8 . . . . . . . . 8
| |
7 . . . . . . -P . 7
| |
6 . . . . . . -P -K 6
| |
5 . . . . . . -P . 5
| |
4 . . . . . . . . 4
| |
3 . -P . . . . . . 3
| |
2 . P . -P . . . . 2
| |
1 . . K R . . . . 1
| |
+---a---b---c---d---e---f---g---h---+
r#2 3 + 6

1.Kc1-b1 ! threat:
2.Rd1-e1
2...d2*e1=Q #
2...d2*e1=R #

In fact, there is Zugzwang, since after the key, White at the move would have to deliver mate by 2.Rd1-h1#

[Thomas Maeder]

Fixed in development head and future versions