#910: --make should have a -j flag for parallel building -------------------------------------+------------------------------------- Reporter: igloo | Owner: Type: feature request | Status: closed Priority: normal | Milestone: ⊥ Component: Compiler | Version: 6.4.2 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: N/A Blocked By: 8184, 8235 | Blocking: Related Tickets: #9221 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nh2): @rrnewton: That may or may not be a good idea - since tools like stack already do a `-j` on the package level, it seems that the best results can be achieved if such tools are aware of GHC's `-j` and use it correctly (e.g. you'd probably not want full `-j` for both stack and GHC as that would give you N*N threads and a lot of overhead) - so it may be worth more pushing for these tools to use GHC's `-j`. Also, if there was a `GHC_MAKE_CORES` env var, and `-j` was also given, which one would take precedence? To answer one of your questions directly, most of these tools accept a `--ghc-options` flag, e.g. you can do `stack build --ghc-options="-j4"`. I think another reason why not all tools use `ghc -j` is because of #9221. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/910#comment:64 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler