compiz crashed with SIGSEGV in _int_malloc() from __libc_calloc() from XOpenDisplay() from nux::WindowThread::ThreadCtor()

StacktraceTop:
 _int_malloc (av=0x7fd9449db720, bytes=16384) at malloc.c:3697
 __libc_calloc (n=<optimized out>, elem_size=<optimized out>) at malloc.c:3274
 XOpenDisplay (display=<optimized out>) at ../../src/OpenDis.c:256
 nux::WindowThread::ThreadCtor (this=0x1809a00, X11Display=0x0, X11Window=347, OpenGLContext=0x8ec6e8) at ./WindowThread.cpp:1104
 nux::CreateFromForeignWindow (X11Window=347, OpenGLContext=0x8ec6e8, user_init_func=0x7fd9307b6be0 <unity::UnityScreen::initUnity(nux::NThread*, void*)>, data=0xe91880) at ./Nux.cpp:210

Status changed to 'Confirmed' because the bug affects multiple users.

So I'm able to reproduce this, or at lease the call to nux::WindowThread::ThreadCtor() which then calls XOpenDisplay(NULL), which then fails.

To reproduce:
1) Open CCSM (CompizConfig Settings Manager)
2) Disable Unity Plugin
3) Enable Unity Plugin

Repeat steps 2 and 3 until a crash! There was also a different crash I was getting that I have to look into...

This error occurs when Compiz-Fusion "Desktop Wall" is enabled. After startup the destop "edge-flipping" does not work even when enabled. Using Compiz Config to disable the Desktop Wall and then re-enable the Desktop Wall causes the proper edge-flipping behavior to resume but also causes this error.

Hello theevilbeast, or anyone else affected,

Accepted unity into precise-proposed. The package will build now and be available in a few hours. Please test and give feedback here. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you in advance!

This bug was fixed in the package unity - 5.12-0ubuntu1

---------------
unity (5.12-0ubuntu1) precise-proposed; urgency=low

  * New upstream release.
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      (LP: #952378)
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      from unity::dash::ResultViewGrid::~ResultViewGrid() from
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    - compiz crashed with SIGSEGV in
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      std::basic_string<char> >, char const*, boost::algorithm::is_iequal>()
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      fro...