• Douglas Wilson's avatar
    Compile modules that are needed by template haskell, even with -fno-code. · 53c78be0
    Douglas Wilson authored
    This patch relates to Trac #8025
    
    The goal here is to enable typechecking of packages that contain some
    template haskell. Prior to this patch, compilation of a package with
    -fno-code would fail if any functions in the package were called from
    within a splice.
    
    downsweep is changed to do an additional pass over the modules,
    targetting any ModSummaries transitively depended on by a module that
    has LangExt.TemplateHaskell enabled. Those targeted modules have
    hscTarget changed from HscNothing to the default target of the platform.
    
    There is a small change to the prevailing_target logic to enable this.
    
    A simple test is added.
    
    I have benchmarked with and without a patched haddock
    (available:https://github.com/duog/haddock/tree/wip-no-explicit-th-compi
    lation).  Running cabal haddock on the wreq package results in a 25%
    speedup on my machine:
    
    time output from patched cabal haddock:
    
    real    0m5.780s
    user    0m5.304s
    sys     0m0.496s
    time output from unpatched cabal haddock:
    
    real    0m7.712s
    user    0m6.888s
    sys     0m0.736s
    
    Reviewers: austin, bgamari, ezyang
    
    Reviewed By: bgamari
    
    Subscribers: bgamari, DanielG, rwbarton, thomie
    
    GHC Trac Issues: #8025
    
    Differential Revision: https://phabricator.haskell.org/D3441
    53c78be0
DynFlags.hs 219 KB