Oh I mean copy elision. std::string str; do_something(str); return str;
Something like this. Or factory function: std::string foo() { return factory(a.begin(),a.end()); } Sometimes the first one does not guarantee to happen? Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows From: Jonathan Wakely<mailto:jwakely....@gmail.com> Sent: Monday, November 15, 2021 03:05 To: unlvsur unlvsur<mailto:unlv...@live.com> Cc: gcc@gcc.gnu.org<mailto:gcc@gcc.gnu.org> Subject: Re: Can I provide a hint to gcc for return value optimization? On Mon, 15 Nov 2021, 06:47 unlvsur unlvsur via Gcc, <gcc@gcc.gnu.org<mailto:gcc@gcc.gnu.org>> wrote: I want give a hint to gcc that allows std::string to rvo. Is that possible? Any attribute for doing that? It's already allowed, and will be done automatically whenever it's possible.