#0  ~basic_string (this=0x7fff66e136e0, __in_chrg=<optimized out>) at /usr/include/c++/4.7/bits/basic_string.h:536
No locals.
#1  pkgProblemResolver::DoUpgrade (this=0x7fff66e13710, Pkg=<incomplete type>) at algorithms.cc:730
        P = <incomplete type>
        Start = {<pkgCache::Iterator<pkgCache::Dependency, pkgCache::DepIterator>> = {<std::iterator<std::forward_iterator_tag, pkgCache::Dependency, long, pkgCache::Dependency*, pkgCache::Dependency&>> = {<No data fields>}, _vptr.Iterator = 0x3ad, S = 0x4, Owner = 0x7fff66e1377f}, Type = (unknown: 1726036312)}
        End = {<pkgCache::Iterator<pkgCache::Dependency, pkgCache::DepIterator>> = {<std::iterator<std::forward_iterator_tag, pkgCache::Dependency, long, pkgCache::Dependency*, pkgCache::Dependency&>> = {<No data fields>}, _vptr.Iterator = 0x6102bfff30, S = 0xce2818, Owner = 0x6b1d58}, Type = (unknown: 13419392)}
        D = {<pkgCache::Iterator<pkgCache::Dependency, pkgCache::DepIterator>> = {<std::iterator<std::forward_iterator_tag, pkgCache::Dependency, long, pkgCache::Dependency*, pkgCache::Dependency&>> = {<No data fields>}, _vptr.Iterator = 0xcbfe80, S = 0x1601960, Owner = 0xb09400}, Type = (unknown: 4466924)}
        group = {cache = @0xe75060, released = false}
        WasKept = false
        Fail = <optimized out>
#2  0x00007f2111a07580 in __GI___libc_malloc (bytes=0) at malloc.c:2859
        ar_ptr = 0x0
        victim = 0xe75060
        __func__ = "__libc_malloc"
#3  0x0000000000db28a0 in ?? ()
No symbol table info available.
#4  0x00000000027128d0 in ?? ()
No symbol table info available.
#5  0x0000000000a0de90 in ?? ()
No symbol table info available.
#6  0x0000000100000000 in ?? ()
No symbol table info available.
#7  0x0000000000000000 in ?? ()
No symbol table info available.