1. 30 Dec, 2015 1 commit
  2. 28 Dec, 2015 1 commit
    • Herbert Valerio Riedel's avatar
      Synchronise ghci-package version with ghc-package · 01299ca8
      Herbert Valerio Riedel authored
      In order to simplify the task, the version munging logic has
      been radically simplified:
      
      Previously, in cases where the version contained dates as version components,
      the build-system would munge the version of the stage1 ghc package before
      registering the `ghc` package.
      
      However, this hack was already questionable at the time of its introduction
      (c.f. 7b45c46c).
      Simplifying the build-systems by avoiding such hacks may also help the
      shaking-up-ghc effort.
      
      So now we simply munge directly via the `.cabal` files, which gives a simpler
      picture, as now every stage is munged the same. Munging is only active when
      the first patch-level version component is a date. So stable snapshots and release
      candidates are unaffacted (as those have the date in the second patch-level
      version component)
      
      Reviewers: simonmar, bgamari, austin, thomie, ezyang
      
      Reviewed By: bgamari, thomie, ezyang
      
      Differential Revision: https://phabricator.haskell.org/D1673
      01299ca8
  3. 17 Dec, 2015 1 commit
    • Simon Marlow's avatar
      Remote GHCi, -fexternal-interpreter · 4905b83a
      Simon Marlow authored
      Summary:
      (Apologies for the size of this patch, I couldn't make a smaller one
      that was validate-clean and also made sense independently)
      
      (Some of this code is derived from GHCJS.)
      
      This commit adds support for running interpreted code (for GHCi and
      TemplateHaskell) in a separate process.  The functionality is
      experimental, so for now it is off by default and enabled by the flag
      -fexternal-interpreter.
      
      Reaosns we want this:
      
      * compiling Template Haskell code with -prof does not require
        building the code without -prof first
      
      * when GHC itself is profiled, it can interpret unprofiled code, and
        the same applies to dynamic linking.  We would no longer need to
        force -dynamic-too with TemplateHaskell, and we can load ordinary
        objects into a dynamically-linked GHCi (and vice versa).
      
      * An unprofiled GHCi can load and run profiled code, which means it
        can use the stack-trace functionality provided by profiling without
        taking the performance hit on the compiler that profiling would
        entail.
      
      Amongst other things; see
      https://ghc.haskell.org/trac/ghc/wiki/RemoteGHCi for more details.
      
      Notes on the implementation are in Note [Remote GHCi] in the new
      module compiler/ghci/GHCi.hs.  It probably needs more documenting,
      feel free to suggest things I could elaborate on.
      
      Things that are not currently implemented for -fexternal-interpreter:
      
      * The GHCi debugger
      * :set prog, :set args in GHCi
      * `recover` in Template Haskell
      * Redirecting stdin/stdout for the external process
      
      These are all doable, I just wanted to get to a working validate-clean
      patch first.
      
      I also haven't done any benchmarking yet.  I expect there to be slight hit
      to link times for byte code and some penalty due to having to
      serialize/deserialize TH syntax, but I don't expect it to be a serious
      problem.  There's also lots of low-hanging fruit in the byte code
      generator/linker that we could exploit to speed things up.
      
      Test Plan:
      * validate
      * I've run parts of the test suite with
      EXTRA_HC_OPTS=-fexternal-interpreter, notably tests/ghci and tests/th.
      There are a few failures due to the things not currently implemented
      (see above).
      
      Reviewers: simonpj, goldfire, ezyang, austin, alanz, hvr, niteria, bgamari, gibiansky, luite
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1562
      4905b83a