govet: skip fieldalignment test on 32bit platforms

[realsn0w]

the govet fieldalignment test currently fails on 32bit targets because it assumes uintptr always has a size of 8 bytes.
this pr (edited after some discussion) adds build tags to skip it on platforms where that is not the case.

[boring-cyborg]

Hey, thank you for opening your first Pull Request !

[CLAassistant]

All committers have signed the CLA.

[ldez]

Hello, in which context do you need to run our tests inside a 32-bit arch?

[realsn0w]

ran into this while working on the golangci-lint void package.
ci there runs a check stage after build for non-cross targets.
here is an example of a build failure caused by this.

also just in general, i feel like it would be nice if the tests work for all of the platforms you currently support / provide official binaries for (which currently includes armv6/7 and i386).

[ldez]

We will not be able to maintain those tests because our CI doesn't use 32-bit arch (we will not add it inside our CI) and globally 32-bit arches are dead but 🤷

I don't understand why distribution packagers want to recompile everything and run tests: this is a Go program (statically linked) with no usage of CGO, not a C program dynamically linked.
A re-compilation has no real advantages in this context, and running tests is a bit of a waste of CPU cycles because we already run them, but I don't want to enter into a debate here.

I will just ask to remove 32-bit tests because they will never be run inside our CI.
We will keep the build tags.

[realsn0w]

alright, that sounds like a fair compromise.
thanks for the quick replies 🙂

[ldez]

LGTM