Selectively reduce optimisation level in GHC build
Currently there are a few places in the GHC build where we do signficantly more time than is necessary or warranted, especially during development:
ghc-cabalis built with
$SRC_HC_OPTS, which contains
-Oin most build flavours. This means that we end up spending a significant amount of time compiling an optimized
Cabal, despite the fact that stage0
ghc-cabalis hardly a performance critical executable.
Cabalis built with
HsLibHcOpts, which contains
-Oin most build flavours. Not only is
Cabaltypically not going to be performance critical for users, but the object size from an unoptimised build is significantly smaller than that from an optimised build.