Python Error while building code using waf

Question

I had code that worked fine. I shut down my PC (Ubuntu) and then, built the same software (ns-3) and now I get the error:

Traceback (most recent call last):
  File "./waf", line 148, in <module>
    Scripting.prepare(t, cwd, VERSION, wafdir)
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Scripting.py", line 102, in prepare
    prepare_impl(t,cwd,ver,wafdir)
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Scripting.py", line 95, in prepare_impl
    main()
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Scripting.py", line 130, in main
    fun(ctx)
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Scripting.py", line 269, in build
    bld=check_configured(bld)
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Scripting.py", line 219, in check_configured
    bld.load_dirs(proj[SRCDIR],proj[BLDDIR])
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Build.py", line 245, in load_dirs
    self.load()
  File "/home/ns-allinone-3.6/ns-3.6/.waf-1.5.8-12763e767c863088b8579dbeeb8265b6/wafadmin/Build.py", line 78, in load
    if f:data=cPickle.load(f)
EOFError

I am just amazed at this, how could 2 minutes before everything was fine and now I am screwed by this error.

What should I do, I am totally bewildered. I have a deadline and suddenly this code stops, it worked fine, only change I did was to switch off my PC.

Answer 1

NS-3.6 is a very very old ns-3 release which you are trying to build with a new system (gcc compiler, python etc). I think the only solution to solve the problem is to update the simulator to a new release.

Try to rebuild it. First write: rm -rf build and build from scratch