Re: Two questions about building GHC from sources

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1. If my bootstrap compiler changes (e.g., from 8.10.5 to 9.0.1), is Hadrian smart enough to rebuild everything? If not, how do I force it to start over?

(1), I would hope so. If not, that's a bug.

I have confirmed that when the bootstrap compiler changes, Hadrian cannot successfully rebuild GHC. Reproducing the fault takes 11 steps, one of which is a full GHC build, so it's a bit time-consuming. The second build fails with an uncaught exception in Shake. I've reported the bug as issue #20429. Norman