minecraft crash bug

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OS: Windows 7 (ver 6.1, arch amd64)
Java: 1.8.0_25 (by Oracle Corporation)
Launcher: Minecraft Launcher 1.6.11 (bootstrap 100)
Minecraft: 1.8.4 (updated Fri Apr 17 15:37:50 GST 2015)
What I expected to happen was...:
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What actually happened was...:
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Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...