I asked this question on StackOverflow from the aspect of C++. There are some guys provided useful hints:

http://stackoverflow.com/questions/23451982/is-it-unsafe-to-store-derived-object-to-void-then-cast-base-object-out-of-it

In reply to Re^4: Perlxs and C++ inheritance by llancet
in thread Perlxs and C++ inheritance by llancet

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