Configure the build to use the CC toolchain's linker for GHC >= 9.0.1

Fixes #1736

haskell/cabal.bzl

@@ -172,10 +172,11 @@ def _cabal_toolchain_info(hs, cc, workspace_name, runghc):
         runghc = runghc.path,
         ar = ar,
         cc = cc.tools.cc,
+        ld = cc.tools.ld,
         strip = cc.tools.strip,
         is_windows = hs.toolchain.is_windows,
         workspace = workspace_name,
-        ghc_cc_args = ghc_cc_program_args(hs, "$CC"),
+        ghc_cc_args = ghc_cc_program_args(hs, "$CC", "$LD"),
     )
 
 def _prepare_cabal_inputs(

haskell/cc.bzl

@@ -186,11 +186,12 @@ def cc_interop_info(ctx, override_cc_toolchain = None):
         ]).linking_context.linker_inputs.to_list() for lib in li.libraries],
     )
 
-def ghc_cc_program_args(hs, cc):
+def ghc_cc_program_args(hs, cc, ld):
     """Returns the -pgm* flags required to override cc.
 
     Args:
       cc: string, path to the C compiler (cc_wrapper).
+      ld: string, path to the linker (ld).
 
     Returns:
       list of string, GHC arguments.
@@ -220,4 +221,11 @@ def ghc_cc_program_args(hs, cc):
     ]
     if hs.toolchain.numeric_version >= [8, 10, 3]:
         args.append("-pgmc-supports-no-pie")
+    if hs.toolchain.numeric_version >= [9, 0, 1]:
+        args.extend([
+            "-pgmlm",
+            ld,
+            "-optlm",
+            "-r",
+        ])
     return args

haskell/doctest.bzl

@@ -98,7 +98,7 @@ def _haskell_doctest_single(target, ctx):
         ctx,
         override_cc_toolchain = hs.tools_config.maybe_exec_cc_toolchain,
     )
-    args.add_all(ghc_cc_program_args(hs, cc.tools.cc))
+    args.add_all(ghc_cc_program_args(hs, cc.tools.cc, cc.tools.ld))
 
     doctest_log = ctx.actions.declare_file(
         "doctest-log-" + ctx.label.name + "-" + target.label.name,

haskell/private/cabal_wrapper.py

@@ -131,6 +131,7 @@ def canonicalize_path(path):
 
 ar = find_exe(toolchain_info["ar"])
 cc = find_exe(toolchain_info["cc"])
+ld = find_exe(toolchain_info["ld"])
 strip = find_exe(toolchain_info["strip"])
 
 def recache_db():
@@ -263,10 +264,14 @@ def distdir_prefix():
         "--with-hsc2hs=" + hsc2hs,
         "--with-ar=" + ar,
         "--with-gcc=" + cc,
+        "--with-ld=" + ld,
         "--with-strip=" + strip,
         "--enable-deterministic", \
         ] +
-        [ "--ghc-option=" + flag.replace("$CC", cc) for flag in toolchain_info["ghc_cc_args"] ] +
+        [ "--ghc-option=" + flag.replace("$CC", cc).replace("$LD", ld) for flag in toolchain_info["ghc_cc_args"] ] +
+        [ "--hsc2hs-option=-c" + cc,
+          "--hsc2hs-option=-l" + cc,
+        ] +
         [ "--ghc-option=-optl@" + os.path.join(cfg_execroot, f) for f in [extra_ldflags_file] if f ] +
         enable_relocatable_flags + \
         [ \

haskell/repl.bzl

@@ -396,7 +396,12 @@ def _create_repl(hs, cc, posix, ctx, repl_info, output):
         "$RULES_HASKELL_EXEC_ROOT",
         hs.toolchain.cc_wrapper.executable.path,
     )
-    args.extend(['"{}"'.format(arg) for arg in ghc_cc_program_args(hs, cc_path)])
+    ld_path = paths.join(
+        "$RULES_HASKELL_EXEC_ROOT",
+        cc.ld_executable,
+    )
+    args.extend(['"{}"'.format(arg) for arg in ghc_cc_program_args(hs, cc_path, ld_path)])
+
 
     # Load source files
     # Force loading by source with `:add *...`.
@@ -518,7 +523,8 @@ def _create_hie_bios(hs, cc, posix, ctx, repl_info, path_prefix):
     path_prefix = paths.join("", *path_prefix)
     args, inputs = _compiler_flags_and_inputs(hs, cc, repl_info, path_prefix = path_prefix, static = True)
     cc_path = paths.join(path_prefix, hs.toolchain.cc_wrapper.executable.path)
-    args.extend(ghc_cc_program_args(hs, cc_path))
+    ld_path = paths.join(path_prefix, cc.ld_executable)
+    args.extend(ghc_cc_program_args(hs, cc_path, ld_path))
     args.extend(hs.toolchain.ghcopts)
     args.extend(repl_info.load_info.compiler_flags)
 

haskell/toolchain.bzl

@@ -46,7 +46,7 @@ def _run_ghc(hs, cc, inputs, outputs, mnemonic, arguments, env, params_file = No
 
     # 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.
-    args.add_all(ghc_cc_program_args(hs, cc.tools.cc))
+    args.add_all(ghc_cc_program_args(hs, cc.tools.cc, cc.tools.ld))
 
     compile_flags_file = hs.actions.declare_file("compile_flags_%s_%s_%s" % (hs.name, extra_name, mnemonic))
     extra_args_file = hs.actions.declare_file("extra_args_%s_%s_%s" % (hs.name, extra_name, mnemonic))