[Bug 27354] New: winediag:X11DRV_WineGL_InitOpenglInfo The Mesa OpenGL driver is using software rendering, most likely your OpenGL drivers haven't been installed correctly

http://bugs.winehq.org/show_bug.cgi?id=27354

Summary: winediag:X11DRV_WineGL_InitOpenglInfo The Mesa OpenGL
                    driver is using software rendering, most likely your
                    OpenGL drivers haven't been installed correctly
           Product: Wine
           Version: 1.3.21
          Platform: x86-64
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: directx-d3d
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

I'm using Gnome Shell so I'm pretty sure that OpenGL is NOT using software
rendering (wouldn't work).
How does wine detect this?