[ok123456]

Lack of standards compliance, bugs, and generally unhelpful compilation error reporting. It was a nightmare for the OOP class, which used more compiler features. Couple that with undergraduate sophomores and juniors trying to do things at the last moment, and you'll have a lot of former CS majors.

[jjjjoe]

Sounds like the sort of program that'd give you a 0 on an assignment if it worked perfectly but emitted a compiler warning under Sun Studio