[cfe-dev] Proposed C++ optimization with big speed gains with big objects

[Ladislav Nevery]

Skyscrapper city[1000]; 
city[1] = Skyscrapper("Empire State Building"); 


              city[1].~Skyscraper(); // release member resources aquired by
default constructor 
try new (&city[1]) Skyscraper("empire state building"); catch(...) { //
cleanup 
     new (&city[1]) Skyscraper()  // reaquire member resources aquired by
default constructor 
     throw; 
} 

this will make code behave like in standard. ie 
in exception handler you get object in state after default initialization
yet preventing default copy happening even when things are fine. 
Optimization will skip the objects calling anything except memset from
default constructor to solve reinvocation state machine change. 



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