Hannes Siebenhandl pushed to branch wip/fendor/dep-json at Glasgow Haskell Compiler / GHC

Commits:

• 8c2b7e98
  by fendor at 2026-11-05T10:06:37+01:00

  Add `-dep-json` flag to `ghc -M`
  
  Add an optional flag to `ghc -M` that allows to write the dependency
  information in JSON Lines format.
  
  The JSON Lines format enables us to stream the output of the dependency
  generation to a consumer.
  The output of `-dep-json` is streamed to a temporary file and then
  copied to the final destination to avoid partial writes.
  
  Each line contains one of two possible json objects:
  
    1. A Home Unit Dependency
        * Contains the name of the home module, its unit, where it is
          located, whether a preprocessor is used, and all of its imports.
          Importantly, the imports include `-XExplicitLevelImports`
          information.
        * If requested via `-include-pkg-deps`, includes imports of external
          units, e.g. modules from `base`.
        * If requested via `-include-cpp-deps`, files included via CPP.
    2. External Unit Dependency
        * Only if `-include-pkg-deps` is given
        * Contains unit-id, its package name and package id.
  
  ---
  
  This PR refactors the Makefile generation to use phases appropriately.
  
  We introduce an intermediate data structure that is generated based on
  the module graph nodes, and only then generate the Makefile rules.
  This allows the dep-json and dep-makefile generation to use the same
  dependency processing.
  

• 44afdb4b
  by fendor at 2026-11-05T10:08:56+01:00

  Add multiple home unit support to `ghc -M`
  
  Allows to process the module graph of multiple home units at once using
  the same syntax as `--make` and `--interactive`:
  
      ghc -M -unit @unitA -unit @unitB
  
  The semantics are identical to `--make` and `--interactive`.
  
  Each home unit can declare individually to use `-include-cpp-deps` and
  `-include-pkg-deps`.
  However, there can only be one output file, and `-dep-json` and
  `-dep-makefile` can only be provided at the top of the cli invocation.
  
  We introduce a new GHC API `doMkDepend` that allows to use multiple home
  units conveniently.
  
  The output of `-dep-json` and `-dep-makefile` does not change, since we
  were careful to choose a format that supports multiple home units from
  the start.
  
  Single home units are still accepted like before with no changes.
  

• 084bd1ec
  by fendor at 2026-11-05T10:08:56+01:00

  Deprecate `doMkDependHS` in favour of `doMkDepend`
  

64 changed files:

• + changelog.d/make-depends-deprecate-doMkDependHS
• + changelog.d/make-depends-json
• + changelog.d/make-depends-multiple-home-units
• compiler/GHC/Driver/DynFlags.hs
• compiler/GHC/Driver/MakeFile.hs
• compiler/GHC/Driver/Session.hs
• compiler/GHC/Driver/Session/Units.hs
• compiler/GHC/Utils/Json.hs
• + docs/users_guide/make-depends-json-schema-1_0.json
• docs/users_guide/separate_compilation.rst
• ghc/Main.hs
• testsuite/driver/testglobals.py
• testsuite/driver/testlib.py
• + testsuite/tests/driver/mkdepend/Makefile
• + testsuite/tests/driver/mkdepend/README.md
• + testsuite/tests/driver/mkdepend/T24384/A.hs
• + testsuite/tests/driver/mkdepend/T24384/C.hs
• + testsuite/tests/driver/mkdepend/T24384/C.hs-boot
• + testsuite/tests/driver/mkdepend/T24384/D.hs
• + testsuite/tests/driver/mkdepend/T24384/E.hs
• + testsuite/tests/driver/mkdepend/T24384/dep-internal/DepInternal.hs
• + testsuite/tests/driver/mkdepend/T24384/dep-internal/dep-internal.pkg
• + testsuite/tests/driver/mkdepend/T24384/dep-public/DepPublic.hs
• + testsuite/tests/driver/mkdepend/T24384/dep-public/dep-public.pkg
• + testsuite/tests/driver/mkdepend/T24384/dep/Dep.hs
• + testsuite/tests/driver/mkdepend/T24384/dep/dep.pkg
• + testsuite/tests/driver/mkdepend/T24384/foo.h
• + testsuite/tests/driver/mkdepend/T24384/lib/B.hs
• + testsuite/tests/driver/mkdepend/T24384/lib/B.hs-boot
• + testsuite/tests/driver/mkdepend/T24384/preproc.sh
• + testsuite/tests/driver/mkdepend/T24384a.stdout
• + testsuite/tests/driver/mkdepend/T24384b.stdout
• + testsuite/tests/driver/mkdepend/T24384c.stdout
• + testsuite/tests/driver/mkdepend/all.T
• + testsuite/tests/driver/mkdepend/format_json.sh
• + testsuite/tests/driver/mkdepend/format_makefile.sh
• + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs
• + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs-boot
• + testsuite/tests/driver/mkdepend/mhu01/a/A/TH.hs
• + testsuite/tests/driver/mkdepend/mhu01/a/Util.hs
• + testsuite/tests/driver/mkdepend/mhu01/b/B/Normal.hs
• + testsuite/tests/driver/mkdepend/mhu01/b/B/Splice.hs
• + testsuite/tests/driver/mkdepend/mhu01/b/Util.hs
• + testsuite/tests/driver/mkdepend/mhu01/c/C.hs
• + testsuite/tests/driver/mkdepend/mhu01/unitA
• + testsuite/tests/driver/mkdepend/mhu01/unitB
• + testsuite/tests/driver/mkdepend/mhu01/unitC
• + testsuite/tests/driver/mkdepend/mhu02/A.hs
• + testsuite/tests/driver/mkdepend/mhu02/B.hs
• + testsuite/tests/driver/mkdepend/mhu02/pp.sh
• + testsuite/tests/driver/mkdepend/mhu02/unitA
• + testsuite/tests/driver/mkdepend/mhu02/unitB
• + testsuite/tests/driver/mkdepend/mhu03/pkg/A.hs
• + testsuite/tests/driver/mkdepend/mhu03/pkg/pp.sh
• + testsuite/tests/driver/mkdepend/mhu03/unitA
• + testsuite/tests/driver/mkdepend/mkdepend01.dep-json
• + testsuite/tests/driver/mkdepend/mkdepend01.dep-makefile
• + testsuite/tests/driver/mkdepend/mkdepend01/A.hs
• + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-json
• + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-makefile
• + testsuite/tests/driver/mkdepend/mkdepend_mhu02.dep-json
• + testsuite/tests/driver/mkdepend/mkdepend_mhu03.dep-json
• testsuite/tests/perf/compiler/large-project/all.T
• + testsuite/tests/perf/compiler/large-project/large-project-mhu.sh

The diff was not included because it is too large.