more apt runtime failures

[Justin Pryzby <justinpryzby@users.sourceforge.net>]

While in one window I saw:

$ sudo aptitude install libc6-dev-amd64
Reading package lists... Done
Building dependency tree... Done
Reading extended state information
Initializing package states... Done
Writing extended state information... Done

In another I got:

$ apt-cache policy aptitude
terminate called after throwing an instance of 'std::bad_alloc'
  what():  std::bad_alloc
Aborted
$ apt-cache policy aptitude
aptitude:
  Installed: 0.4.4-4
[...]

It seems to me that aptitude should not do things at this stage that
will break user apt processes.