make unspecified-repr be another combinatoric lever?

[Gankra]

Without a specified calling convention, we generate a test for every possible calling convention. We could also do the same thing for type repr (C, Rust, u8, ...). (Right now unspecified => repr C)

If we want to do this, it would have to become a new member of TestOptions, and therefore a part of every TestKey

abi-cafe/src/abis/mod.rs

Lines 90 to 98 in 6ba6865

	/// Options for a test
	#[derive(Clone, Debug, Serialize)]
	pub struct TestOptions {
	/// The calling convention
	pub convention: CallingConvention,
	pub functions: FunctionSelector,
	pub val_writer: WriteImpl,
	pub val_generator: ValueGeneratorKind,
	}

I think the absolute amount of work involved isn't perse a ton, and I hopefully setup the code such that adding a new TestOptions field will give you compiler errors everywhere you need to deal with it.

That said it's a lot of tedious threading of options and has some weird decisions to make around "how do you prevent repr(rust) types from getting shoved into extern "C" interfaces (or do you?).