diff options
Diffstat (limited to 'third_party/bazel/rules_haskell/haskell/toolchain.bzl')
| -rw-r--r-- | third_party/bazel/rules_haskell/haskell/toolchain.bzl | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/third_party/bazel/rules_haskell/haskell/toolchain.bzl b/third_party/bazel/rules_haskell/haskell/toolchain.bzl new file mode 100644 index 0000000000..b05d51ea3b --- /dev/null +++ b/third_party/bazel/rules_haskell/haskell/toolchain.bzl @@ -0,0 +1,334 @@ +"""Rules for defining toolchains""" + +load("@bazel_skylib//lib:paths.bzl", "paths") +load(":ghc_bindist.bzl", "haskell_register_ghc_bindists") +load( + ":private/actions/compile.bzl", + "compile_binary", + "compile_library", +) +load( + ":private/actions/link.bzl", + "link_binary", + "link_library_dynamic", + "link_library_static", +) +load(":private/actions/package.bzl", "package") + +_GHC_BINARIES = ["ghc", "ghc-pkg", "hsc2hs", "haddock", "ghci", "runghc", "hpc"] + +def _run_ghc(hs, cc, inputs, outputs, mnemonic, arguments, params_file = None, env = None, progress_message = None, input_manifests = None): + if not env: + env = hs.env + + args = hs.actions.args() + args.add(hs.tools.ghc) + + # Do not use Bazel's CC toolchain on Windows, as it leads to linker and librarty compatibility issues. + # XXX: We should also tether Bazel's CC toolchain to GHC's, so that we can properly mix Bazel-compiled + # C libraries with Haskell targets. + if not hs.toolchain.is_windows: + args.add_all([ + # GHC uses C compiler for assemly, linking and preprocessing as well. + "-pgma", + cc.tools.cc, + "-pgmc", + cc.tools.cc, + "-pgml", + cc.tools.cc, + "-pgmP", + cc.tools.cc, + # Setting -pgm* flags explicitly has the unfortunate side effect + # of resetting any program flags in the GHC settings file. So we + # restore them here. See + # https://ghc.haskell.org/trac/ghc/ticket/7929. + "-optc-fno-stack-protector", + "-optP-E", + "-optP-undef", + "-optP-traditional", + ]) + + compile_flags_file = hs.actions.declare_file("compile_flags_%s_%s" % (hs.name, mnemonic)) + extra_args_file = hs.actions.declare_file("extra_args_%s_%s" % (hs.name, mnemonic)) + + args.set_param_file_format("multiline") + arguments.set_param_file_format("multiline") + hs.actions.write(compile_flags_file, args) + hs.actions.write(extra_args_file, arguments) + + extra_inputs = [ + hs.tools.ghc, + # Depend on the version file of the Haskell toolchain, + # to ensure the version comparison check is run first. + hs.toolchain.version_file, + compile_flags_file, + extra_args_file, + ] + cc.files + + if params_file: + params_file_src = params_file.path + extra_inputs.append(params_file) + else: + params_file_src = "<(:)" # a temporary file with no contents + + script = """ +export PATH=${PATH:-} # otherwise GCC fails on Windows + +# this is equivalent to 'readarray'. We do not use 'readarray' in order to +# support older bash versions. +while IFS= read -r line; do compile_flags+=("$line"); done < %s +while IFS= read -r line; do extra_args+=("$line"); done < %s +while IFS= read -r line; do param_file_args+=("$line"); done < %s + +"${compile_flags[@]}" "${extra_args[@]}" ${param_file_args+"${param_file_args[@]}"} +""" % (compile_flags_file.path, extra_args_file.path, params_file_src) + + ghc_wrapper_name = "ghc_wrapper_%s_%s" % (hs.name, mnemonic) + ghc_wrapper = hs.actions.declare_file(ghc_wrapper_name) + hs.actions.write(ghc_wrapper, script, is_executable = True) + extra_inputs.append(ghc_wrapper) + + if type(inputs) == type(depset()): + inputs = depset(extra_inputs, transitive = [inputs]) + else: + inputs += extra_inputs + + hs.actions.run_shell( + inputs = inputs, + input_manifests = input_manifests, + outputs = outputs, + command = ghc_wrapper.path, + mnemonic = mnemonic, + progress_message = progress_message, + env = env, + arguments = [], + ) + + return args + +def _haskell_toolchain_impl(ctx): + # Store the binaries of interest in ghc_binaries. + ghc_binaries = {} + for tool in _GHC_BINARIES: + for file in ctx.files.tools: + if tool in ghc_binaries: + continue + + basename_no_ext = paths.split_extension(file.basename)[0] + if tool == basename_no_ext: + ghc_binaries[tool] = file + elif "%s-%s" % (tool, ctx.attr.version) == basename_no_ext: + ghc_binaries[tool] = file + if not tool in ghc_binaries: + fail("Cannot find {} in {}".format(tool, ctx.attr.tools.label)) + + # Run a version check on the compiler. + version_file = ctx.actions.declare_file("ghc-version") + ghc = ghc_binaries["ghc"] + ctx.actions.run_shell( + inputs = [ghc], + outputs = [version_file], + mnemonic = "HaskellVersionCheck", + command = """ +{ghc} --numeric-version > {version_file} +if [[ "{expected_version}" != "$(< {version_file})" ]] +then + echo ERROR: GHC version does not match expected version. + echo Your haskell_toolchain specifies {expected_version}, + echo but you have $(< {version_file}) in your environment. +exit 1 +fi + """.format( + ghc = ghc.path, + version_file = version_file.path, + expected_version = ctx.attr.version, + ), + ) + + # Get the versions of every prebuilt package. + ghc_pkg = ghc_binaries["ghc-pkg"] + pkgdb_file = ctx.actions.declare_file("ghc-global-pkgdb") + ctx.actions.run_shell( + inputs = [ghc_pkg], + outputs = [pkgdb_file], + mnemonic = "HaskellPackageDatabaseDump", + command = "{ghc_pkg} dump --global > {output}".format( + ghc_pkg = ghc_pkg.path, + output = pkgdb_file.path, + ), + ) + + tools_struct_args = { + name.replace("-", "_"): file + for name, file in ghc_binaries.items() + } + + locale_archive = None + + if ctx.attr.locale_archive != None: + locale_archive = ctx.file.locale_archive + + return [ + platform_common.ToolchainInfo( + name = ctx.label.name, + tools = struct(**tools_struct_args), + compiler_flags = ctx.attr.compiler_flags, + repl_ghci_args = ctx.attr.repl_ghci_args, + haddock_flags = ctx.attr.haddock_flags, + locale = ctx.attr.locale, + locale_archive = locale_archive, + osx_cc_wrapper_tpl = ctx.file._osx_cc_wrapper_tpl, + mode = ctx.var["COMPILATION_MODE"], + actions = struct( + compile_binary = compile_binary, + compile_library = compile_library, + link_binary = link_binary, + link_library_dynamic = link_library_dynamic, + link_library_static = link_library_static, + package = package, + run_ghc = _run_ghc, + ), + is_darwin = ctx.attr.is_darwin, + is_windows = ctx.attr.is_windows, + version = ctx.attr.version, + # Pass through the version_file, that it can be required as + # input in _run_ghc, to make every call to GHC depend on a + # successful version check. + version_file = version_file, + global_pkg_db = pkgdb_file, + ), + ] + +_haskell_toolchain = rule( + _haskell_toolchain_impl, + attrs = { + "tools": attr.label_list( + doc = "GHC and executables that come with it. First item take precedance.", + mandatory = True, + ), + "compiler_flags": attr.string_list( + doc = "A collection of flags that will be passed to GHC on every invocation.", + ), + "repl_ghci_args": attr.string_list( + doc = "A collection of flags that will be passed to GHCI on repl invocation. It extends the `compiler_flags` collection. Flags set here have precedance over `compiler_flags`.", + ), + "haddock_flags": attr.string_list( + doc = "A collection of flags that will be passed to haddock.", + ), + "version": attr.string( + doc = "Version of your GHC compiler. It has to match the version reported by the GHC used by bazel.", + mandatory = True, + ), + "is_darwin": attr.bool( + doc = "Whether compile on and for Darwin (macOS).", + mandatory = True, + ), + "is_windows": attr.bool( + doc = "Whether compile on and for Windows.", + mandatory = True, + ), + "locale": attr.string( + default = "en_US.UTF-8", + doc = "Locale that will be set during compiler invocations.", + ), + "locale_archive": attr.label( + allow_single_file = True, + doc = """ +Label pointing to the locale archive file to use. Mostly useful on NixOS. +""", + ), + "_osx_cc_wrapper_tpl": attr.label( + allow_single_file = True, + default = Label("@io_tweag_rules_haskell//haskell:private/osx_cc_wrapper.sh.tpl"), + ), + }, +) + +def haskell_toolchain( + name, + version, + tools, + exec_compatible_with = None, + target_compatible_with = None, + compiler_flags = [], + repl_ghci_args = [], + haddock_flags = [], + locale_archive = None, + **kwargs): + """Declare a compiler toolchain. + + You need at least one of these declared somewhere in your `BUILD` files + for the other rules to work. Once declared, you then need to *register* + the toolchain using `register_toolchains` in your `WORKSPACE` file (see + example below). + + Example: + + In a `BUILD` file: + + ```bzl + haskell_toolchain( + name = "ghc", + version = "1.2.3", + tools = ["@sys_ghc//:bin"], + compiler_flags = ["-Wall"], + ) + ``` + + where `@sys_ghc` is an external repository defined in the `WORKSPACE`, + e.g. using: + + ```bzl + nixpkgs_package( + name = 'sys_ghc', + attribute_path = 'haskell.compiler.ghc822', + ) + + register_toolchains("//:ghc") + ``` + """ + if exec_compatible_with and not target_compatible_with: + target_compatible_with = exec_compatible_with + elif target_compatible_with and not exec_compatible_with: + exec_compatible_with = target_compatible_with + impl_name = name + "-impl" + corrected_ghci_args = repl_ghci_args + ["-no-user-package-db"] + _haskell_toolchain( + name = impl_name, + version = version, + tools = tools, + compiler_flags = compiler_flags, + repl_ghci_args = corrected_ghci_args, + haddock_flags = haddock_flags, + visibility = ["//visibility:public"], + is_darwin = select({ + "@io_tweag_rules_haskell//haskell/platforms:darwin": True, + "//conditions:default": False, + }), + is_windows = select({ + "@io_tweag_rules_haskell//haskell/platforms:mingw32": True, + "//conditions:default": False, + }), + # Ignore this attribute on any platform that is not Linux. The + # LOCALE_ARCHIVE environment variable is a Linux-specific + # Nixpkgs hack. + locale_archive = select({ + "@io_tweag_rules_haskell//haskell/platforms:linux": locale_archive, + "//conditions:default": None, + }), + **kwargs + ) + native.toolchain( + name = name, + toolchain_type = "@io_tweag_rules_haskell//haskell:toolchain", + toolchain = ":" + impl_name, + exec_compatible_with = exec_compatible_with, + target_compatible_with = target_compatible_with, + ) + +def haskell_register_toolchains(version): + """Download the binary distribution of GHC for your current platform + and register it as a toolchain. This currently has the same effect + as just `haskell_register_ghc_bindists(version)`. + """ + haskell_register_ghc_bindists(version) |