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[Bug 259219] Re: Broken TLS support in libGL.so

 

** Description changed:

  Binary package hint: libgl1-mesa-dri
  
  ---
+ Software Center error description from apport is:  software-center crashed with SIGSEGV in __cxa_allocate_exception()
  WORKAROUND for the software-center crash:
  
-   Launch Software Center from the command line as:
+   Launch Software Center from the command line as:
  
-      LD_PRELOAD=/usr/lib/libstdc++.so.6 software-center
+      LD_PRELOAD=/usr/lib/libstdc++.so.6 software-center
  
  This should only be needed the first time; after this Software Center
  should launch correctly without needing the command line.
  
  For more details about the software-center crash, please see bug 731724.
  ---
  
  The package libgl1-mesa-dri in Intrepid seems to have been compiled with the option --enable-glx-tls. This triggers a bug in src/glx/x11/glxcurrent.c :
  The TLS variable __glX_tls_Context is compiled with the TLS model initial-exec, which is only ment for executables. Used in shared libraries, it can break TLS usage in other shared libraries.
  One example is when libGL is linked beforce libstdc++ in another library, which is then loaded via dlopen(). In this case, the TLS variables in libstdc++ aren't properly initialized, and it will segfault when trying to allocate an exception.
  I think there are 2 possible solutions:
  1. Do not compile with --enabgle-glx-tls
  2. Patch mesa to remove the tls-model attribute. I assume this will eat up the performance gain of TLS, since initial-exec is meant as an optimisation for apps not using the GL over dlopen directly or indirectly.
  
  Policy information about my libGL package:
  libgl1-mesa-dri:
    Installiert: 7.1~rc3-1ubuntu4
    Kandidat: 7.1~rc3-1ubuntu4
    Versions-Tabelle:
   *** 7.1~rc3-1ubuntu4 0
          500 http://de.archive.ubuntu.com intrepid/main Packages
          100 /var/lib/dpkg/status

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https://bugs.launchpad.net/bugs/259219

Title:
  Broken TLS support in libGL.so