llvm dev - May 2019 - Passing Twine by value

Twine.h says twines should only be accepted as const references in arguments,
but there are a bunch of functions that take Twine by value (e.g. you'll
find lots of them in CGObjCMac.cpp in clang). Is this just a potential
performance issue, or are there potential correctness issues from passing a
twine by value as well?
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I don't believe there's any correctness issue with passing Twine by
value.

Not sure it'd even be a performance problem - the sizeof(Twine) looks like
it'd be small enough (like StringRef - though a bit bigger, StringRef
should be two words, Twine would be three) not to worry too much either way.


On Thu, May 30, 2019 at 12:14 AM Shoaib Meenai via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> Twine.h says twines should only be accepted as const references in
> arguments, but there are a bunch of functions that take Twine by value
> (e.g. you'll find lots of them in CGObjCMac.cpp in clang). Is this just
a
> potential performance issue, or are there potential correctness issues from
> passing a twine by value as well?
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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