Include Gold linker in requirements.

Updates #26.

PiperOrigin-RevId: 195303940
Change-Id: I833cee55b5df6196ed90c1f8987c3c9c07204678

3 files changed, 102 insertions, 125 deletions

diff --git a/README.md b/README.md
index 65075de0e..8bf795cb5 100644
--- a/README.md
+++ b/README.md
@@ -171,6 +171,7 @@ and Docker.
 * [Python 2.7][python] (See [bug #8](https://github.com/google/gvisor/issues/8)
   for Python 3 support updates)
 * [Docker version 17.09.0 or greater][docker]
+* Gold linker (e.g. `binutils-gold` package on Ubuntu)
 
 ### Getting the source
 
diff --git a/tools/go_generics/defs.bzl b/tools/go_generics/defs.bzl
index 0b2467805..214e0dfca 100644
--- a/tools/go_generics/defs.bzl
+++ b/tools/go_generics/defs.bzl
@@ -1,26 +1,26 @@
 def _go_template_impl(ctx):
-  input = ctx.files.srcs
-  output = ctx.outputs.out
-
-  args = ["-o=%s" % output.path] + [f.path for f in input]
-
-  ctx.actions.run(
-      inputs = input,
-      outputs = [output],
-      mnemonic = "GoGenericsTemplate",
-      progress_message = "Building Go template %s" % ctx.label,
-      arguments = args,
-      executable = ctx.executable._tool,
-  )
-
-  return struct(
-      types = ctx.attr.types,
-      opt_types = ctx.attr.opt_types,
-      consts = ctx.attr.consts,
-      opt_consts = ctx.attr.opt_consts,
-      deps = ctx.attr.deps,
-      file = output,
-  )
+    input = ctx.files.srcs
+    output = ctx.outputs.out
+
+    args = ["-o=%s" % output.path] + [f.path for f in input]
+
+    ctx.actions.run(
+        inputs = input,
+        outputs = [output],
+        mnemonic = "GoGenericsTemplate",
+        progress_message = "Building Go template %s" % ctx.label,
+        arguments = args,
+        executable = ctx.executable._tool,
+    )
+
+    return struct(
+        types = ctx.attr.types,
+        opt_types = ctx.attr.opt_types,
+        consts = ctx.attr.consts,
+        opt_consts = ctx.attr.opt_consts,
+        deps = ctx.attr.deps,
+        file = output,
+    )
 
 """
 Generates a Go template from a set of Go files.
@@ -39,81 +39,73 @@ Args:
   opt_consts: the list of constants in the template that can but aren't required to be specified.
   deps: the list of dependencies.
 """
-
 go_template = rule(
+    implementation = _go_template_impl,
     attrs = {
-        "srcs": attr.label_list(
-            mandatory = True,
-            allow_files = True,
-        ),
+        "srcs": attr.label_list(mandatory = True, allow_files = True),
         "deps": attr.label_list(allow_files = True),
         "types": attr.string_list(),
         "opt_types": attr.string_list(),
         "consts": attr.string_list(),
         "opt_consts": attr.string_list(),
-        "_tool": attr.label(
-            executable = True,
-            cfg = "host",
-            default = Label("//tools/go_generics:go_merge"),
-        ),
+        "_tool": attr.label(executable = True, cfg = "host", default = Label("//tools/go_generics:go_merge")),
     },
     outputs = {
         "out": "%{name}_template.go",
     },
-    implementation = _go_template_impl,
 )
 
 def _go_template_instance_impl(ctx):
-  template = ctx.attr.template
-  output = ctx.outputs.out
-
-  # Check that all required types are defined.
-  for t in template.types:
-    if t not in ctx.attr.types:
-      fail("Missing value for type %s in %s" % (t, ctx.attr.template.label))
-
-  # Check that all defined types are expected by the template.
-  for t in ctx.attr.types:
-    if (t not in template.types) and (t not in template.opt_types):
-      fail("Type %s it not a parameter to %s" % (t, ctx.attr.template.label))
-
-  # Check that all required consts are defined.
-  for t in template.consts:
-    if t not in ctx.attr.consts:
-      fail("Missing value for constant %s in %s" % (t, ctx.attr.template.label))
-
-  # Check that all defined consts are expected by the template.
-  for t in ctx.attr.consts:
-    if (t not in template.consts) and (t not in template.opt_consts):
-      fail("Const %s it not a parameter to %s" % (t, ctx.attr.template.label))
-
-  # Build the argument list.
-  args = ["-i=%s" % template.file.path, "-o=%s" % output.path]
-  args += ["-p=%s" % ctx.attr.package]
-
-  if len(ctx.attr.prefix) > 0:
-    args += ["-prefix=%s" % ctx.attr.prefix]
-
-  if len(ctx.attr.suffix) > 0:
-    args += ["-suffix=%s" % ctx.attr.suffix]
-
-  args += [("-t=%s=%s" % (p[0], p[1])) for p in ctx.attr.types.items()]
-  args += [("-c=%s=%s" % (p[0], p[1])) for p in ctx.attr.consts.items()]
-  args += [("-import=%s=%s" % (p[0], p[1])) for p in ctx.attr.imports.items()]
-
-  ctx.actions.run(
-      inputs = [template.file],
-      outputs = [output],
-      mnemonic = "GoGenericsInstance",
-      progress_message = "Building Go template instance %s" % ctx.label,
-      arguments = args,
-      executable = ctx.executable._tool,
-  )
-
-  # TODO: How can we get the dependencies out?
-  return struct(
-      files = depset([output])
-  )
+    template = ctx.attr.template
+    output = ctx.outputs.out
+
+    # Check that all required types are defined.
+    for t in template.types:
+        if t not in ctx.attr.types:
+            fail("Missing value for type %s in %s" % (t, ctx.attr.template.label))
+
+            # Check that all defined types are expected by the template.
+    for t in ctx.attr.types:
+        if (t not in template.types) and (t not in template.opt_types):
+            fail("Type %s it not a parameter to %s" % (t, ctx.attr.template.label))
+
+            # Check that all required consts are defined.
+    for t in template.consts:
+        if t not in ctx.attr.consts:
+            fail("Missing value for constant %s in %s" % (t, ctx.attr.template.label))
+
+            # Check that all defined consts are expected by the template.
+    for t in ctx.attr.consts:
+        if (t not in template.consts) and (t not in template.opt_consts):
+            fail("Const %s it not a parameter to %s" % (t, ctx.attr.template.label))
+
+            # Build the argument list.
+    args = ["-i=%s" % template.file.path, "-o=%s" % output.path]
+    args += ["-p=%s" % ctx.attr.package]
+
+    if len(ctx.attr.prefix) > 0:
+        args += ["-prefix=%s" % ctx.attr.prefix]
+
+    if len(ctx.attr.suffix) > 0:
+        args += ["-suffix=%s" % ctx.attr.suffix]
+
+    args += [("-t=%s=%s" % (p[0], p[1])) for p in ctx.attr.types.items()]
+    args += [("-c=%s=%s" % (p[0], p[1])) for p in ctx.attr.consts.items()]
+    args += [("-import=%s=%s" % (p[0], p[1])) for p in ctx.attr.imports.items()]
+
+    ctx.actions.run(
+        inputs = [template.file],
+        outputs = [output],
+        mnemonic = "GoGenericsInstance",
+        progress_message = "Building Go template instance %s" % ctx.label,
+        arguments = args,
+        executable = ctx.executable._tool,
+    )
+
+    # TODO: How can we get the dependencies out?
+    return struct(
+        files = depset([output]),
+    )
 
 """
 Instantiates a Go template by replacing all generic types with concrete ones.
@@ -128,13 +120,10 @@ Args:
   imports: the map from imports used in types/consts to their import paths.
   package: the name of the package the instantiated template will be compiled into.
 """
-
 go_template_instance = rule(
+    implementation = _go_template_instance_impl,
     attrs = {
-        "template": attr.label(
-            mandatory = True,
-            providers = ["types"],
-        ),
+        "template": attr.label(mandatory = True, providers = ["types"]),
         "prefix": attr.string(),
         "suffix": attr.string(),
         "types": attr.string_dict(),
@@ -142,11 +131,6 @@ go_template_instance = rule(
         "imports": attr.string_dict(),
         "package": attr.string(mandatory = True),
         "out": attr.output(mandatory = True),
-        "_tool": attr.label(
-            executable = True,
-            cfg = "host",
-            default = Label("//tools/go_generics"),
-        ),
+        "_tool": attr.label(executable = True, cfg = "host", default = Label("//tools/go_generics")),
     },
-    implementation = _go_template_instance_impl,
 )
diff --git a/tools/go_stateify/defs.bzl b/tools/go_stateify/defs.bzl
index 87fdc0d28..60a9895ff 100644
--- a/tools/go_stateify/defs.bzl
+++ b/tools/go_stateify/defs.bzl
@@ -23,27 +23,27 @@ go_library(
 """
 
 def _go_stateify_impl(ctx):
-  """Implementation for the stateify tool."""
-  output = ctx.outputs.out
+    """Implementation for the stateify tool."""
+    output = ctx.outputs.out
 
-  # Run the stateify command.
-  args = ["-output=%s" % output.path]
-  args += ["-pkg=%s" % ctx.attr.package]
-  if ctx.attr._statepkg:
-    args += ["-statepkg=%s" % ctx.attr._statepkg]
-  if ctx.attr.imports:
-    args += ["-imports=%s" % ",".join(ctx.attr.imports)]
-  args += ["--"]
-  for src in ctx.attr.srcs:
-    args += [f.path for f in src.files]
-  ctx.actions.run(
-      inputs = ctx.files.srcs,
-      outputs = [output],
-      mnemonic = "GoStateify",
-      progress_message = "Generating state library %s" % ctx.label,
-      arguments = args,
-      executable = ctx.executable._tool,
-  )
+    # Run the stateify command.
+    args = ["-output=%s" % output.path]
+    args += ["-pkg=%s" % ctx.attr.package]
+    if ctx.attr._statepkg:
+        args += ["-statepkg=%s" % ctx.attr._statepkg]
+    if ctx.attr.imports:
+        args += ["-imports=%s" % ",".join(ctx.attr.imports)]
+    args += ["--"]
+    for src in ctx.attr.srcs:
+        args += [f.path for f in src.files]
+    ctx.actions.run(
+        inputs = ctx.files.srcs,
+        outputs = [output],
+        mnemonic = "GoStateify",
+        progress_message = "Generating state library %s" % ctx.label,
+        arguments = args,
+        executable = ctx.executable._tool,
+    )
 
 """
 Generates save and restore logic from a set of Go files.
@@ -56,22 +56,14 @@ Args:
   out: the name of the generated file output. This must not conflict with any other files and must be added to the srcs of the relevant go_library.
   package: the package name for the input sources.
 """
-
 go_stateify = rule(
+    implementation = _go_stateify_impl,
     attrs = {
-        "srcs": attr.label_list(
-            mandatory = True,
-            allow_files = True,
-        ),
+        "srcs": attr.label_list(mandatory = True, allow_files = True),
         "imports": attr.string_list(mandatory = False),
         "package": attr.string(mandatory = True),
         "out": attr.output(mandatory = True),
-        "_tool": attr.label(
-            executable = True,
-            cfg = "host",
-            default = Label("//tools/go_stateify:stateify"),
-        ),
+        "_tool": attr.label(executable = True, cfg = "host", default = Label("//tools/go_stateify:stateify")),
         "_statepkg": attr.string(default = "gvisor.googlesource.com/gvisor/pkg/state"),
     },
-    implementation = _go_stateify_impl,
 )