GoLink: force external link for static binaries (#2175)
By default on Linux, the Go linker may produce a static binary if no
packages require cgo. net and os both require cgo, so for non-trivial
programs, the external linker will NOT be used, and the internal
linker will produce a dynamically linked executable.
With this change, in static mode, we force external linking. We were
already passing -static to the external linker, but we weren't always
using the external linker.
Fixes #2168
diff --git a/go/private/actions/link.bzl b/go/private/actions/link.bzl
index e7fae98..df8fcea 100644
--- a/go/private/actions/link.bzl
+++ b/go/private/actions/link.bzl
@@ -79,11 +79,12 @@
tool_args.add("-race")
if go.mode.msan:
tool_args.add("-msan")
+ if go.mode.static or go.mode.link != LINKMODE_NORMAL:
+ tool_args.add("-linkmode", "external")
if go.mode.static:
extldflags.append("-static")
if go.mode.link != LINKMODE_NORMAL:
builder_args.add("-buildmode", go.mode.link)
- tool_args.add("-linkmode", "external")
if go.mode.link == LINKMODE_PLUGIN:
tool_args.add("-pluginpath", archive.data.importpath)
diff --git a/tests/core/go_binary/BUILD.bazel b/tests/core/go_binary/BUILD.bazel
index 9df9b7f..e09506e 100644
--- a/tests/core/go_binary/BUILD.bazel
+++ b/tests/core/go_binary/BUILD.bazel
@@ -103,3 +103,32 @@
rundir = ".",
deps = ["@io_bazel_rules_go//go/tools/bazel:go_default_library"],
)
+
+go_test(
+ name = "static_test",
+ srcs = ["static_test.go"],
+ data = select({
+ "@io_bazel_rules_go//go/platform:linux": [
+ ":static_cgo_bin",
+ ":static_pure_bin",
+ ],
+ "//conditions:default": [],
+ }),
+ rundir = ".",
+ deps = ["//go/tools/bazel:go_default_library"],
+)
+
+go_binary(
+ name = "static_cgo_bin",
+ srcs = ["static_cgo_bin.go"],
+ cgo = True,
+ static = "on",
+ tags = ["manual"],
+)
+
+go_binary(
+ name = "static_pure_bin",
+ srcs = ["static_pure_bin.go"],
+ static = "on",
+ tags = ["manual"],
+)
diff --git a/tests/core/go_binary/README.rst b/tests/core/go_binary/README.rst
index 61bf662..1851c76 100644
--- a/tests/core/go_binary/README.rst
+++ b/tests/core/go_binary/README.rst
@@ -2,6 +2,7 @@
=============================
.. _go_binary: /go/core.rst#_go_binary
+.. _#2168: https://github.com/bazelbuild/rules_go/issues/2168
Tests to ensure the basic features of go_binary are working as expected.
@@ -38,7 +39,15 @@
depend on values from the workspace status script. Verifies #2000.
pie_test
-----------
+--------
Tests that specifying the ``linkmode`` attribute on a `go_binary`_ target to be
pie produces a position-independent executable and that no specifying it produces
a position-dependent binary.
+
+static_test
+-----------
+Test that `go_binary`_ rules with ``static = "on"`` with and without cgo
+produce static binaries. Verifies `#2168`_.
+
+This test only runs on Linux. The darwin external linker cannot produce
+static binaries since there is no static version of C runtime libraries.
diff --git a/tests/core/go_binary/static_cgo_bin.go b/tests/core/go_binary/static_cgo_bin.go
new file mode 100644
index 0000000..65676fd
--- /dev/null
+++ b/tests/core/go_binary/static_cgo_bin.go
@@ -0,0 +1,14 @@
+package main
+
+/*
+#include <stdio.h>
+
+void say_hello() {
+ printf("hello\n");
+}
+*/
+import "C"
+
+func main() {
+ C.say_hello()
+}
diff --git a/tests/core/go_binary/static_pure_bin.go b/tests/core/go_binary/static_pure_bin.go
new file mode 100644
index 0000000..1dbaa12
--- /dev/null
+++ b/tests/core/go_binary/static_pure_bin.go
@@ -0,0 +1,8 @@
+package main
+
+import (
+ _ "net"
+ _ "os"
+)
+
+func main() {}
diff --git a/tests/core/go_binary/static_test.go b/tests/core/go_binary/static_test.go
new file mode 100644
index 0000000..5dc50ca
--- /dev/null
+++ b/tests/core/go_binary/static_test.go
@@ -0,0 +1,45 @@
+// Copyright 2019 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+
+package static_cgo_test
+
+import (
+ "debug/elf"
+ "testing"
+
+ "github.com/bazelbuild/rules_go/go/tools/bazel"
+)
+
+func TestStatic(t *testing.T) {
+ for _, name := range []string{"static_cgo_bin", "static_pure_bin"} {
+ t.Run(name, func(t *testing.T) {
+ path, ok := bazel.FindBinary("tests/core/go_binary", name)
+ if !ok {
+ t.Fatal("could not find static_cgo_bin")
+ }
+ f, err := elf.Open(path)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer f.Close()
+ for _, prog := range f.Progs {
+ if prog.Type == elf.PT_INTERP {
+ t.Fatalf("binary %s has PT_INTERP segment, indicating dynamic linkage", path)
+ }
+ }
+ })
+ }
+}
