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Cherry-Pick #7562: [NFC] Address compiler warnings: C4146 - Use two's complement instead of negation#8239

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Cherry-Pick #7562: [NFC] Address compiler warnings: C4146 - Use two's complement instead of negation#8239
alsepkow wants to merge 1 commit intomicrosoft:release-1.8.2505from
alsepkow:user/alsepkow/cherry-pick-7562-to-1.8.2505

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@alsepkow alsepkow commented Mar 7, 2026

Cherry-pick of PR #7562 into release-1.8.2505.

Original PR: #7562
Original Commit: b390fb1

Assisted by GitHub Copilot.

… of negation (microsoft#7562)

Replaces uses of the unary - operator on signed integers with the
equivalent (sort of, see the details below) expression '~N + 1',
assigning the result to an unsigned type. This avoids undefined behavior
in edge cases and ensures correctness when certain conditions are met.

Details:
This transformation is valid when:

The signed value N is guaranteed to be negative.
The result is stored in an unsigned type that can represent the full
range of the signed type (e.g., uint64_t for int64_t).
The system uses two's complement representation (as is standard on
modern platforms).
While -N is undefined for the minimum representable value (e.g.,
INT64_MIN), the expression ~N + 1 remains well-defined and yields the
correct bit pattern. Assigning this result to an appropriately sized
unsigned type preserves the intended two's complement interpretation
without triggering undefined behavior.

Addresses microsoft#7561.
@alsepkow alsepkow changed the title Cherry-Pick: [NFC] Address compiler warnings: C4146 - Use two's complement instead of negation (#7562) Cherry-Pick #7562: [NFC] Address compiler warnings: C4146 - Use two's complement instead of negation Mar 7, 2026
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