LibSass: heap-use-after-free in Sass::SharedPtr::incRefCount()

Feeding @Pif0,0::SharedImplSass::Expression /home/geeknik/libsass/src/memory/SharedPtr.hpp:141:23 3 0x9820a2 in Sass::Eval::operatorSass::FunctionCall /home/geeknik/libsass/src/eval.cpp:1018 4 0x951b36 in Sass::Eval::operatorSass::List /home/geeknik/libsass/src/eval.cpp:502:18 5 0x9a0042 in...