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  1. Qt
  2. QTBUG-126674

Inconsistent hashing between bool and integral overloads

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Details

    • 3
    • 878077de2 (dev), 81adaf909 (dev), 72c3ae0a8 (6.8), 13d2398e0 (6.7), 705cec8ac (tqtc/lts-6.5)
    • Foundation Sprint 110, Foundation Sprint 111, Foundation Sprint 112

    Description

      Besides QTBUG-116080, we also have an unintended implementation of qHash(bool) via the 1-to-2-arg adapter (QTBUG-116971) and qHash(int). The two functions differ in the relative sequence of seed xoring and bit-mixing, making

      • qHash(1, seed),
      • qHash(true, seed)

      produce different values, for general seed != 0.

      This doesn't look fixable in Qt 6, as all involved overloads are inline, therefore immutable.

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-116064 [REG SiC 6.4 -> 6.5] qHash(qfloat16(x)) is now ambiguous on GCC13

          • P1: Critical - Urgent and Important, will STOP the release if matched with set FixVersion field. This includes regressions from the last version that are not edge cases; Data loss; Build issues; All but the most unlikely crashes/lockups/hanging; Serious usability issues and embarrassing bugs & Bugs critical to a deliverable. This is the highest possible priority for requirements.
          • Closed
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              mmutz Marc Mutz
              mmutz Marc Mutz
              Vladimir Minenko Vladimir Minenko
              Alex Blasche Alex Blasche
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              Dates

                Created:
                Updated:
                Resolved:

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