alt Hacker NewsIn my experience C++ abstractions give the optimizer a harder job and thus it generates worse code. In this case, different code is emitted by clang if you write a C version[0] versus C++ original[1].
Usually abstraction like this means that the compiler has to emit generic code which is then harder to flow through constraints and emit the same final assembly since it's less similar to the "canonical" version of the code that wouldn't use a magic `==` (in this case) or std::vector methods or something else like that.
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pjmlp • last Saturday at 4:32 PM
Except that the C++ version doesn't need to be like that.
Abstractions are welcome when it doesn't matter, when it matters there are other ways to write the code and it keeps being C++ compliant.
To back up the other commenter - it's not the same. https://godbolt.org/z/r6e443x1c shows that if you write imperfect C++ clang is perfectly capable of optimizing it.