[gnugo-devel] life & death (3.3.5)

[Paul Pogonyshev]

sorry, i don't have 3.3.6 sources at the moment, so this may already
have been fixed.

in the position below black is to play, state of the white group is
ko. since there're no threats, it is alive.

if gnu go plays black, it setups the ko and, of course, loses it:
  a8 - a7
  c8 - a9
  e3 - a8

i tried to play black and started an attack that can be answered:
  a7 - a8
  a6 - e3 ???   this mistake killed the entire white group
  a5 - f3
  g3 - pass

the strangest thing is that gnu go thinks that white group is still
alive and that black stones inside are dead. even if all white stones
was connected, it would be seki!

from its point of view, black c8 makes white group dead, black e4
makes the position seki and black e4 followed by f4 kills white
stones.

regards,
  Paul Pogonyshev

(;
FF[4]
GM[1]
SZ[9]
AB[ag][ah][ba][bh][ca][cf][ch][da][db][dc][dd][de][df][dh][ee][eh][fb][fe][fh][gc][gf]
AW[af][bb][bd][bf][bg][cc][cd][ce][cg][dg]
GN[1]
)