Question

What flag(s) do I need on the command line to disable the return-value optimisation automatically enabled by the g++ compiler?

Answer 1

-fno-elide-constructors

The C++ standard allows an implementation to omit creating a temporary which is only used to initialize another object of the same type. Specifying this option disables that optimization, and forces G++ to call the copy constructor in all cases. [Source: man gcc]

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