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Followup to zkcrypto#46 which attempted to change an assertion for the window size from `<= 64` to `< 64`, which was in response to the `width` type being `u64` and its value computed as `1 << window`, which would overflow a `u64`. This means `width` needs an extra bit, so this promotes it to a `u128` while keeping any variables that can remain `u64` as they were.
tarcieri
commented
Feb 6, 2026
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Is there a good way to test this? |
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As I was looking at this I thought there was already a lot of casting, and adding in wider types only makes things worse. Since we need to compute let width_div_2 = 1u64 << (window - 1); // window is asserted >= 2
let window_mask = width_div_2 | (width_div_2 - 1); // fill in 1s for all the lower 0 bitsI guess you still need let width = (width_div_2 as i128) * 2;
((window_val as i128) - width) as i64Edit: went ahead and made this change in 6a7d96a |
tarcieri
commented
Feb 7, 2026
| - uses: actions/checkout@v4 | ||
| - run: cargo fetch | ||
| # Requires #![deny(rustdoc::broken_intra_doc_links)] in crates. | ||
| - run: sudo apt-get -y install libfontconfig1-dev |
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Same change I made in #71: CI fails with this line present
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Followup to #46 which attempted to change an assertion for the window size from
<= 64to< 64, which was in response to thewidthtype beingu64and its value computed as1 << window, which would overflow au64.This means
widthneeds an extra bit, so this promotes it to au128while keeping any variables that can remainu64as they were.