Align certain records on 8-bit boundary for ARM builds

[iachievedit]

What's in this pull request?

Fixes for ARM build failure introduced by 508e825 (additional info bits added for PointerIntPair GetSetRecord and BehaviorRecord).

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[hpux735]

Thanks, Joe!

[gottesmm]

Do we use these for tagged pointers anywhere?

[hpux735]

By tagged do you mean PointerIntPair? If so, yes. See the linked commit from @jrose-apple . An additional field was added to the enum used in that commit, which necessitated an additional bit in the pointer.

[gottesmm]

So the issue is that there are not enough tagged pointer bits on ARM by default, so we need to manually align due to that change?

[hpux735]

Yep, that's the ticket. I assume it's because ARM is only 32-bit, so the default alignment used on the 64-bit targets is sufficient without this modification.

[gribozavr]

@swift-ci Please smoke test

[gribozavr]

@swift-ci Please test Linux platform

[jrose-apple]

Ah, good catch, sorry for the trouble!

[iachievedit]

No worries, @jrose-apple , thanks for the merge @gribozavr I've kicked off a build for the BeagleBone and Raspberry Pis. Much appreciated!