This unwraps on my system in approx 2 seconds.
arch linux, 64bit, release build.

I thought this may be a stack size bug but even after setting my stack limit from 8mb to 1mb (Winxp uses this), it did not crash, even with a 512kb limit it ran fine.

Can someone else confirm this crash?, assigning to Nathan.

I can unwrap without problems using r34364. I see you have modifications in your revision. Could you attach system-info.txt, please? Generate it in Blender through the Help menu: System Info. You'll find the file in the text editor.

Confirmed in offical 64 bit version. No crash in 32 bit. No crash in more recent version. for ex. 34331 by filiciss. Compiled my self ver. 34391 with scons:
crash again.
Some optimization?

unwraps with non problems here, on linux 64 bit and Blender 34452M just compiled with scons.

I forgot: Windows 7 64 bit

Hrm, I get the crash with a release build, but when running Blender in the debugger unwrapping works fine.

Fixed in r35479 - stack ran out while running the unwrap. I've now doubled the stack size. Thanks for reporting.