An anonymous reader writes: Patrick Wyatt led production efforts for several of Blizzard Entertainment's early games, including Warcraft 1 and 2 and StarCraft. Wyatt has just published an in-depth look at the development of StarCraft, highlighting many of the problems the team encountered, and several of the hacks they came to regret later. Quoting: 'Given all the issues working against the team, you might think it was hard to identify a single large source of bugs, but based on my experiences the biggest problems in StarCraft related to the use of doubly-linked linked lists. Linked lists were used extensively in the engine to track units with shared behavior. With twice the number of units of its predecessor — StarCraft had a maximum of 1600, up from 800 in Warcraft 2 — it became essential to optimize the search for units of specific types by keeping them linked together in lists.
... All of these lists were doubly-linked to make it possible to add and remove elements from the list in constant time — O(1) — without the necessity to traverse the list looking for the element to remove — O(N). Unfortunately, each list was “hand-maintained” — there were no shared functions to link and unlink elements from these lists; programmers just manually inlined the link and unlink behavior anywhere it was required. And hand-rolled code is far more error-prone than simply using a routine that’s already been debugged. ... So the game would blow up all the time. All the time.'