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A comment on A comprehensive guide to 50 years of evolution of strict C programming. Parent comment

Re:A comprehensive guide to 50 years of evolution of strict ... by tpush on Friday November 26, 2021 @04:29AM (#29348693)
Do you have an example of that where C++ struct returns are optimized but not C ones?
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Re:A comprehensive guide to 50 years of evolution of strict ... by jcelerier on Friday November 26, 2021 @06:57AM (#29349443)
enjoy: https://gcc.godbolt.org/z/7Pn8eqhdK

that's latest GCC, at -O3

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Re:A comprehensive guide to 50 years of evolution of strict ... by moonchild on Saturday November 27, 2021 @03:12AM (#29358502)
Clang does generate good code https://gcc.godbolt.org/z/z781r7Phh

But yes, sadly I think it's still generally advisable to avoid returning large structs by value.

Note that this has nothing to do with RVO; as I understand it, RVO is about eliding copy constructors, not actual memory copies, and c has no copy constructors and so gets 'RVO' in all cases.

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