Comment 2 for bug 1510218

I think the issue is that Qt loads platform plugins with RTLD_LAZY so the symbol eglGetConfigAttrib will be lazily resolved.

Now the the mir client platform plugins, declare eglGetConfigAttrib with a weak attribute (as mir plugins are loaded with RTLD_NOW) - so in this case case, the symbol hasn't been resolved so the mir_connection_get_egl_pixel_format resolves to calling a null function pointer.