[Buildroot] problems with make graph-build on x86_64

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear Dallas Clement,

On Thu, 12 Jun 2014 10:29:41 -0500, Dallas Clement wrote:

> I tried a make-graph build for the first time on Debian 7.2 / 32 bit the
> other day.  It worked flawlessly.  Today, I tried it on RHEL 6.4 headless
> server / x86_64.  This time, I got errors I was not able to resolve.
> 
> bash-4.1$ make graph-build
> ./support/scripts/graph-build-time --type=histogram --order=name
> --input=output/build/build-time.log
> --output=output/graphs/build.hist-name.pdf
> Traceback (most recent call last):
>   File "./support/scripts/graph-build-time", line 55, in <module>
>     import matplotlib.pyplot as plt
>   File "/usr/lib64/python2.6/site-packages/matplotlib/pyplot.py", line 78,
> in <module>
>     new_figure_manager, draw_if_interactive, show = pylab_setup()
>   File
> "/usr/lib64/python2.6/site-packages/matplotlib/backends/__init__.py", line
> 25, in pylab_setup
>     globals(),locals(),[backend_name])
>   File
> "/usr/lib64/python2.6/site-packages/matplotlib/backends/backend_gtkagg.py",
> line 10, in <module>
>     from matplotlib.backends.backend_gtk import gtk, FigureManagerGTK,
> FigureCanvasGTK,\
>   File
> "/usr/lib64/python2.6/site-packages/matplotlib/backends/backend_gtk.py",
> line 8, in <module>
>     import gtk; gdk = gtk.gdk
>   File "/usr/lib64/python2.6/site-packages/gtk-2.0/gtk/__init__.py", line
> 64, in <module>
>     _init()
>   File "/usr/lib64/python2.6/site-packages/gtk-2.0/gtk/__init__.py", line
> 52, in _init
>     _gtk.init_check()
> RuntimeError: could not open display
> make: *** [graph-build] Error 1

What version of matplotlib do you have? Seems like it's not using the
PDF or PNG backend, but the Gtk backend, which tries to open a
X11 window.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com