/// Metadata describing how the arguments to a native function

/// should be passed in order to respect the native ABI.

///

/// The signature represented by this type may not match the MIR function signature.

/// Certain attributes, like `#[track_caller]` can introduce additional arguments, which are present in [`FnAbi`], but not in `FnSig`.

/// While this difference is rarely relevant, it should still be kept in mind.

///

/// I will do my best to describe this structure, but these

/// comments are reverse-engineered and may be inaccurate. -NDM

#[derive(Clone, PartialEq, Eq, Hash, HashStable_Generic)]

pub struct FnAbi<'a, Ty> {

/// The LLVM types of each argument.

/// The type, layout, and information about how each argument is passed.

pub args: Box<[ArgAbi<'a, Ty>]>,

/// LLVM return type.

/// The layout, type, and the way a value is returned from this function.

pub ret: ArgAbi<'a, Ty>,

/// Marks this function as variadic (accepting a variable number of arguments).

pub c_variadic: bool,

/// The count of non-variadic arguments.

///

/// Should only be different from args.len() when c_variadic is true.

/// This can be used to know whether an argument is variadic or not.

pub fixed_count: u32,

/// The calling convention of this function.

pub conv: Conv,

/// Indicates if an unwind may happen across a call to this function.

pub can_unwind: bool,

}