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Use base's hDuplicateTo; drop the patched copy - #5117
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`hDuplicateTo'` copied base's `hDuplicateTo` without its `hClose_help` on
the target: closing the descriptor before `dup2` let another thread reuse
it, and `dup2` failed with `EBUSY`. Base fixed this in GHC 9.0.1 ("Avoid
race condition in hDuplicateTo", ghc/ghc!2318); all supported GHC versions
carry the fix. The copy's `DuplexHandle` case still closed the target.
Removes `hDuplicateTo'` from the API of `Development.IDE.GHC.Util` and
`Development.IDE`.
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Development.IDE.GHC.Util.hDuplicateTo'is a copy of base'shDuplicateTowithout thehClose_helpon the target handle. Closing the descriptor beforedup2let another thread reuse the number, anddup2failed withEBUSY(haskell/ghcide#259). The issue was fixed upstream many years ago ("Avoid race condition in hDuplicateTo"; ghc/ghc!2318; since GHC 9.0.1).The copy in HLS was strictly worse than base: its
DuplexHandlecase still calledhClose_help.This PR:
defaultArgumentswithGHC.IO.Handle.hDuplicateTo;hDuplicateTo'and its copied helpers (dupHandleTo,dupHandle_,ioe_dupHandlesNotCompatible).hDuplicateTo'is no longer exported fromDevelopment.IDE.GHC.UtilorDevelopment.IDE. It wasn't used by anything else in HLS.