c++ - Lambda returning a reference causes a segmentation fault - why? -

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the following code taken straight out of 1 of projects. first version causes crash (segmentation fault). second version works intended.

aren't 2 code snippets equivalent?

this 1 crashes

auto getuserfrompacket = [&](sf::packet& mp) -> user&  {      return users.getuser(ssvuj::as<std::string>(getdecompressedpacket(mp), 0));  }; phandler[fromclient::us_death] = [&](clienthandler&, sf::packet& mp)         {     getuserfrompacket(mp).stats.deaths += 1; // segmentation fault here! };

this 1 works

phandler[fromclient::us_death] = [&](clienthandler&, sf::packet& mp)         {     users.getuser(ssvuj::as<std::string>(getdecompressedpacket(mp), 0)).stats.deaths += 1;      // works fine };

compiler used: clang++ 3.4 - couldn't deduce return type of getuserfrompacket. users instance of userdb. function signature user& userdb::getuser(const std::string&) - why compiler fail deduce user& return type?

no, aren't equivalent. first 1 refer lambda, (likely) not in scope time needed. second has no such dependency. careful capturing reference. :)


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