Code-size optimisation for top-level indirections (#7308)
Top-level indirections are often generated when there is a cast, e.g. foo :: T foo = bar `cast` (some coercion) For these we were generating a full-blown CAF, which is a fair chunk of code. This patch makes these indirections generate a single IND_STATIC closure (4 words) instead. This is exactly what the CAF would evaluate to eventually anyway, we're just shortcutting the whole process.