Cheng Shao authored 1 year ago and Marge Bot committed 11 months ago

This data is used alongside Core bindings to reconstruct intermediate
build products when linking Template Haskell splices with bytecode.

Since foreign stubs and files are generated in the pipeline, they were
lost with only Core bindings stored in interfaces.

The interface codec type `IfaceForeign` contains a simplified
representation of `ForeignStubs` and the set of foreign sources that
were manually added by the user.

When the backend phase writes an interface, `mkFullIface` calls
`encodeIfaceForeign` to read foreign source file contents and assemble
`IfaceForeign`.

After the recompilation status check of an upstream module,
`initWholeCoreBindings` calls `decodeIfaceForeign` to restore
`ForeignStubs` and write the contents of foreign sources to the file
system as temporary files.
The restored foreign inputs are then processed by `hscInteractive` in
the same manner as in a regular pipeline.

When linking the stub objects for splices, they are excluded from suffix
adjustment for the interpreter way through a new flag in `Unlinked`.

For details about these processes, please consult Note [Foreign stubs
and TH bytecode linking].

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