I just built beignet in a chroot with no X11 installed; it didn't have
that string, and worked (when run as root - for ordinary users, it
failed with "/dev/dri/card0 not authenticated", but this is expected).
Debian's (with-X) beignet has that string and a few more (__cxx11,
x11_display, x11_screen, x11_dpy).
Did you do the no-X compile by an explicit option, or by not installing
the X headers (libx11-dev, libxext-dev, libxfixes-dev)?
Which clinfo is this (there are at least 3 implementations), and can you
get a backtrace of the error (gdb clinfo)?
beignet doesn't need any kernel patches on recent kernels (>=4.2; check
with uname -r), and in the known cases where it does, the error is
"Beignet: self-test failed" not yours.
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