Summary:
Pull Request resolved: https://github.com/facebookresearch/faiss/pull/3439
LLVM-15 has a warning `-Wunused-but-set-variable` which we treat as an error because it's so often diagnostic of a code issue. Unused variables can compromise readability or, worse, performance.
This diff either (a) removes an unused variable and, possibly, it's associated code, or (b) qualifies the variable with `[[maybe_unused]]`, mostly in cases where the variable _is_ used, but, eg, in an `assert` statement that isn't present in production code.
- If you approve of this diff, please use the "Accept & Ship" button :-)
Reviewed By: palmje, junjieqi
Differential Revision: D57344013
fbshipit-source-id: adf410139d2e6ca69a26ccdbff8511c9b7620489
b8e4489b98