Forge version: 14.23.5.2855
iChunUtil version: 1.12.2-7.2.2
I was playing on last days of humanity modpack in single player when this error occurred. then i tested it in a modpack with just the specified forge version and ichunutil version and it still crashed. So, there are two files in my log folder, one was latest.log and other was debug.log. here are the files:
debug.log the debug log
latest.log the latest log

(I am new to GitHub and this is my first issue post)

never mind guys. it was due to my outdated graphics card. it got fixed when i disabled the stencil in config. leaving this here if anybody comes here with this problem they can see.