ppc64le - fix geoindex/TestS2GeometryIndexBasic failure

[prashantkhoje]

Related #82456
Release note: None

[blathers-crl]

Thank you for contributing to CockroachDB. Please ensure you have followed the guidelines for creating a PR.

My owl senses detect your PR is good for review. Please keep an eye out for any test failures in CI.

I have added a few people who may be able to assist in reviewing:

• @otan (commented on ppc64le - fix geoindex test failures TestS2GeographyIndexBasic and TestS2GeometryIndexBasic #82456)

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is otan.}

[cockroach-teamcity]

This change is 

[otan]

i'm not sure this fix changes the operation; at least, it looks like CI linter thinks not either.

=== RUN   TestLint/TestRoachVet
    lint_test.go:91: 
        pkg/geo/geo.go:759:14: unnecessary conversion
        pkg/geo/geo.go:759:37: unnecessary conversion
        pkg/geo/geo.go:760:3: unnecessary conversion
        pkg/geo/geo.go:760:26: unnecessary conversion
        pkg/geo/geo.go:761:3: unnecessary conversion
        pkg/geo/geo.go:761:26: unnecessary conversion
    --- FAIL: TestLint/TestRoachVet (183.11s)

(schema change test is a flake)
could you elaborate? thanks!

[prashantkhoje]

Platforms like ppc64le and aarch64, use "fused multiply and add" (FMA) instruction that results into rounding differences. The go specification suggests using explicit type conversion to avoid those differences.
Also see disintegration/gift#20 (comment)

[otan]

you'll probably need to add to this to suppress the linter.

cockroach/pkg/testutils/lint/lint_test.go

Line 2151 in e9ee218

filters := []stream.Filter{

please also add a comment about what you just said

[prashantkhoje]

If you can point to some document/example to get me started, it'll be helpful.
I'll also explore linter further.

[blathers-crl]

Thank you for updating your pull request.

My owl senses detect your PR is good for review. Please keep an eye out for any test failures in CI.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is otan.}

[otan]

bors r+

[craig]

Build succeeded:

• GitHub CI (Cockroach)