Simplify calling conventions in favor of CApi

[Bodigrim]

Template B: This PR does not modify behaviour or interface

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• Patches conform to the coding conventions.
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[geekosaur]

This does have me wondering if there's anyone on an old i386 Windows who will want a recent Cabal, though. (I know they can't use a recent ghc, since stdcall went away some versions ago, but pretty sure it's still in some of the ghcs in our support window.)

[Bodigrim]

This does have me wondering if there's anyone on an old i386 Windows who will want a recent Cabal, though.

My understanding is that in principle capi should work even for i386 Windows. I was about to test it, but the last GHC bindist for i386 Windows was 8.6.3, corresponding to base-4.12, while Cabal.cabal already requires at least base-4.13. So it's safe to ignore.

[geekosaur]

Well, "old" here means "pre-NT" anyway. 😀 Which may make it irrelevant anyway, as even the early Win32 APIs for that were ccall IIRC; stdcall aka Pascall calling convention was only for pre-NT syscalls.

[Mikolaj]

We should put these into a museum instead of deleting. ;)