pline recursion loop while getting down the stairs

[Lili1228]

Here's how I compiled it: PKGBUILD

gdb shows a loop pru → newsym → pline → pru. I assume pru triggers hack.pri.c:233, then newsym triggers :308, pline triggers line :404 and so on. Based on that and on fact this only happens sometimes, I assume this is related to level generation.