#12689: DataCon wrappers get in the way of rules -------------------------------------+------------------------------------- Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata): We might want to look at two separate cases: 1. The LHS mentions a data con (wrapper) unsaturated, (`fT` above). 2. The LHS mentions a data con (wrapper) saturated, (`gT` above). In the first case, I think we should simply disable the warning. Because the wrapper is unsaturated, it will not have been inlined in the code. Unsaturation is as good as `NOINLINE`, isn’t it? Only in the latter case it matters that, as you write
after inlining we get a mess of unboxing etc Is really all hope lost that we can match the mess? My gut feeling is that it is more promising to not work against the inliner and simplifier, and rather let it do its jobs (both on the LHS and the code), and try hard to make the matcher smart enough to match the mess.
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