A few days ago I tried to play Quake II (do not laugh - it's the game of all time) on my laptop with Windows 7 and couldn't - the game didn't work. Compatibility mode doesn't give any results.
I found q2source-3.21 archive, builded debug configuration, reassign the paths and ran it. Crash. I started debugging, came to ref_gl initialization and saw that the engine stumbles upon common error - buffer overflow, when trying to output GL_EXTENSIONS string.
The fact is that the constant MAXPRINTMSG (function VID_Printf) equals to 4096, which is not enough for such string in our time - it has grown too much over the years. If you increase the constant by two - the problem goes away. C - unsafe language :)
This problem was solved in OpenGL 3.x, where you don't get the entire list of extensions in one string, but the name of each extension by its index (glGetStringi). SGI had to do that in the initial design of the API, but no one then thought that the extension mechanism will turn into a loony bin, eh?
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