Fix a bug in ChunkedBitSet::subtract#155381
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nnethercote wants to merge 2 commits intorust-lang:mainfrom
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Fix a bug in ChunkedBitSet::subtract#155381nnethercote wants to merge 2 commits intorust-lang:mainfrom
ChunkedBitSet::subtract#155381nnethercote wants to merge 2 commits intorust-lang:mainfrom
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It results in `b64` having many fewer bits set than it should. LLM disclosure: this bug was identified by Claude Code. I did everything else.
It does a masking operation but the mask is computed incorrectly due to operator precedence. The mask is of the form `1 << N - 1` but it should be `(1 << N) - 1` because `-` binds tighter than `1 << N`. This commit fixes the problem, not by adjusting the precedence, but by instead using the existing `clear_excess_bits_in_final_word`, which is consistent with other similar operations. LLM disclosure: this bug was identified by Claude Code. I did everything else.
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An operator precedence bug means an incorrect mask is used in
ChunkedBitSet::subtract. Details in individual commits.r? @dingxiangfei2009