[libcxx-commits] [libcxx] [libc++][ios] Applied `[[nodiscard]]` (PR #173520)

[A. Jiang via libcxx-commits]

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frederick-vs-ja wrote:

I'm a bit reluctant to touch them because they're non-standard. It's possible to say some of them are non-conforming. ([demo](https://godbolt.org/z/4ers9K6b1), in the straight forward reading of the standard wording, there shouldn't be such ambiguity).

Also, the spelling `operator std::streamoff` doesn't seem to be standard-guaranteed. The standard effectively requires `fpos` to have some conversion function, but it may be something other than `operator std::streamoff`.

https://github.com/llvm/llvm-project/pull/173520