What I expected to happen was...:
World generation works 😃
What actually happened was...:
It crashed.
Steps to Reproduce:
1. Create new world
2. Set world type to default
3. Turn generate structures off (this seems to cause the problem)
Simple world generation with same settings, but generate structures off -> crash
on -> don't crash
Environment
OS: Linux (ver 3.13.0-29-generic, arch amd64)
Java: 1.7.0_55 (by Oracle Corporation)
Launcher: Minecraft Launcher 1.4.4 (bootstrap 4)
Minecraft: 14w25a (updated Wed Jun 18 17:52:28 CEST 2014)
Confirmed!