#0  strlen () at ../sysdeps/x86_64/strlen.S:106
  [Error: strlen.S was not found in source tree]
#1  0x00007f642c25ac49 in __add_to_environ (name=0x7f641a6fe9ef "http_proxy", value=0x0, combined=0x0, replace=1) at setenv.c:131
  [Error: setenv.c was not found in source tree]
#2  0x00007f641a6ed5cf in AptIntf::init() () from /tmp/apport_sandbox_wBmXQx/usr/lib/x86_64-linux-gnu/packagekit-backend/libpk_backend_aptcc.so
#3  0x00007f641a6fac00 in pk_backend_resolve_thread(PkBackendJob*, _GVariant*, void*) () from /tmp/apport_sandbox_wBmXQx/usr/lib/x86_64-linux-gnu/packagekit-backend/libpk_backend_aptcc.so
#4  0x000055a83c1d6419 in pk_backend_job_thread_setup ()
#5  0x00007f642c878b65 in g_thread_proxy () from /tmp/apport_sandbox_wBmXQx/lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007f642c5f26fa in start_thread (arg=0x7f64195c9700) at pthread_create.c:333
  [Error: pthread_create.c was not found in source tree]
#7  0x00007f642c3282dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
  [Error: clone.S was not found in source tree]