P3487 R0 Postconditions odr-using a parameter that may be passed in registers

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P3487R0 Postconditions odr-using a parameter that may be passed in registers (Timur Doumler, Joshua Berne)

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Discussed by SG21 on 2024-11-07. Nothing further to do on this paper, closing the issue.

Poll results:

SG21, Teleconference, 2024-11-07

Poll 1:
For P2900, remove postconditions, as proposed in P3487R0 Option R1.
SF F N A SA
0 0 3 9 7

Result: Consensus against

Poll 2:
For P2900, make it ill-formed to odr-use any function parameter in a postcondition, as proposed in P3487R0 Option R2.

Result: By unanimous consent we prefer the R7 to this option.

Poll 3:
For P2900, make it ill-formed to odr-use any non-reference function parameter in a postcondition, as proposed in P3487R0 Option R3.
SF F N A SA
0 5 3 7 3

Result: No consensus

Poll 4:
For P2900, allow the postcondition to see the caller-side version of a parameter; make it ill-formed to odr-use a non-reference function parameter in a postcondition unless the parameter is of scalar type, as proposed in P3487R0 Option R4.

Result: By unanimous consent we prefer the R7 to this option.

Poll 5:
For P2900, allow the postcondition to see the caller-side version of a parameter; make it ill-formed to odr-use a non-reference function parameter in a postcondition if the type of the parameter satisfies the requirements for being
passed via registers, unless it is of scalar type, as proposed in P3487R0 Option R5.

Result: By unanimous consent we prefer the R7 to this option.

Poll 6:
For P2900, allow the postcondition to see the caller-side version of a parameter; make it ill-formed to odr-use a non-reference function parameter in a postcondition if the type of the parameter satisfies the requirements for being
passed via registers and has at least one mutable subobject, as proposed in P3487R0 Option R6.
SF F N A SA
0 0 3 9 7

Result: consensus against

Poll 7:
For P2900, allow the postcondition to see the caller-side version of a parameter; do not introduce any restrictions to odr-use a non-reference function parameter in a postcondition, as proposed in P3487R0 Option R7.
SF F N A SA
11 4 1 1 0

Result: consensus for

Poll 8:
For P2900, clarify that the postcondition is not allowed to see the caller-side version of a parameter, as proposed in P3487R0 Option R8.
Result: By unanimous consent we prefer the R7 to this option.