P3605 R0 isqrt: A function to calculate integer square root of the nonnegative integer

[wg21bot]

P3605R0 isqrt: A function to calculate integer square root of the nonnegative integer (Nikita Sakharin)

[mattkretz]

P3605R0: isqrt: A function to calculate integer square root of the nonnegative integer

2025-06-19 SG6 Minutes

Chair: Matthias Kretz

Champion: Nikita Sakharin

Summary

• SG6 expects no rounding direction other than down.
• Use Constraints instead of Mandates or otherwise explore the difference in the paper and explain why Mandates is preferable.
• Word the type constraint as "signed integer types" and "unsigned integer types"; this excludes the character types.
• Recommendation to consider the <numeric> header rather than <cmath> or <cstdlib>. If C adds isqrt it will need a different name per type and we can't predict whether it will end up in <math.h>.
• Precondition leads to conditional noexcept.

Polls

POLL: Forward P3605R0 to LEWG with the expectation that the discussed action items get explored / discussed in the next revision of the paper.

SF	F	N	A	SA
8	6	0	0	0