When linking mostly-static Linux binaries, link libstdc++.a explicitly. This allows libstdc++ to be statically linked, which is normally only possible when invoking GCC as `g++` with the `-static-libstdc++` flag. Fixes https://github.com/bazelbuild/bazel/issues/2840 See https://github.com/envoyproxy/envoy/issues/415 for additional background and context. cc @htuch (for Envoy) and @calpeyser @hlopko (who I talked to earlier about this) I'm only doing this in the Linux toolchain because MacOS doesn't do static linking of system libs anyway, and I don't know enough about Windows or FreeBSD to test on those platforms. Closes #4031. PiperOrigin-RevId: 178762357
diff --git a/src/test/shell/bazel/BUILD b/src/test/shell/bazel/BUILD index 0f2ddd1..d5a34b2 100644 --- a/src/test/shell/bazel/BUILD +++ b/src/test/shell/bazel/BUILD
@@ -375,6 +375,13 @@ ) sh_test( + name = "cc_static_binary_test", + size = "medium", + srcs = ["cc_static_binary_test.sh"], + data = [":test-deps"], +) + +sh_test( name = "bazel_sandboxing_test", size = "large", srcs = ["bazel_sandboxing_test.sh"],
diff --git a/src/test/shell/bazel/cc_static_binary_test.sh b/src/test/shell/bazel/cc_static_binary_test.sh new file mode 100755 index 0000000..c120ecb --- /dev/null +++ b/src/test/shell/bazel/cc_static_binary_test.sh
@@ -0,0 +1,89 @@ +#!/bin/bash +# +# Copyright 2017 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. +# +# Tests for Bazel's static linking of C++ binaries. + +CURRENT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)" +source "${CURRENT_DIR}/../integration_test_setup.sh" \ + || { echo "integration_test_setup.sh not found!" >&2; exit 1; } + +if ! is_linux; then + echo "Tests for cc_binary static linking currently only run in Linux (this platform is ${PLATFORM})" >&2 + exit 0 +fi + +function set_up() { + mkdir -p cpp/static + cat > cpp/static/main.cc <<EOF +#include <iostream> +int main() { + std::cout << "hello world!\n"; + return 0; +} +EOF +} + +function test_linux_somewhat_static_cc_binary() { + cat > cpp/static/BUILD <<EOF +cc_binary( + name = "somewhat-static", + srcs = ["main.cc"], + linkstatic = 1, +) +EOF + assert_build //cpp/static:somewhat-static +} + +function test_linux_mostly_static_cc_binary() { + cat > cpp/static/BUILD <<EOF +cc_binary( + name = "mostly-static", + srcs = ["main.cc"], + linkstatic = 1, + linkopts = [ + "-static-libstdc++", + "-static-libgcc", + ], +) +EOF + assert_build //cpp/static:mostly-static + LDD_STDOUT=$(ldd bazel-bin/cpp/static/mostly-static) + if [[ "${LDD_STDOUT}" =~ "libstdc++" ]]; then + log_fatal "A mostly-static binary shouldn't dynamically link libstdc++" + fi +} + +function test_linux_fully_static_cc_binary() { + cat > cpp/static/BUILD <<EOF +cc_binary( + name = "fully-static", + srcs = ["main.cc"], + linkstatic = 1, + linkopts = [ + "-static", + "-static-libstdc++", + "-static-libgcc", + ], +) +EOF + assert_build //cpp/static:fully-static + LDD_STDOUT=$(ldd bazel-bin/cpp/static/fully-static || true) + if [[ ! "${LDD_STDOUT}" =~ "not a dynamic executable" ]]; then + log_fatal "Expected a fully-static binary" + fi +} + +run_suite "static cc_binary"
diff --git a/src/test/shell/testenv.sh b/src/test/shell/testenv.sh index fde278e..7594e53 100755 --- a/src/test/shell/testenv.sh +++ b/src/test/shell/testenv.sh
@@ -30,6 +30,10 @@ [[ "${PLATFORM}" =~ darwin ]] } +function is_linux() { + [[ "${PLATFORM}" =~ linux ]] +} + function _log_base() { prefix=$1 shift
diff --git a/tools/cpp/CROSSTOOL.tpl b/tools/cpp/CROSSTOOL.tpl index e75e5e2..2b86bbb 100644 --- a/tools/cpp/CROSSTOOL.tpl +++ b/tools/cpp/CROSSTOOL.tpl
@@ -129,6 +129,7 @@ %{opt_content} } linking_mode_flags { mode: DYNAMIC } +%{link_content} %{coverage}
diff --git a/tools/cpp/unix_cc_configure.bzl b/tools/cpp/unix_cc_configure.bzl index 9814831..e7c099e 100644 --- a/tools/cpp/unix_cc_configure.bzl +++ b/tools/cpp/unix_cc_configure.bzl
@@ -46,6 +46,29 @@ return "\n".join(lines) +def _build_link_content(): + # `-static-libstdc++` is only supported when invoking GCC as `g++`, and + # `-lstdc++` forces dynamic linking of libstdc++. To get desired + # mostly-static behavior, invoke the link by explicitly naming a static + # library archive. + # + # https://github.com/bazelbuild/bazel/issues/2840 + return """ + linking_mode_flags { + mode: DYNAMIC + linker_flag: "-lstdc++" + } + linking_mode_flags { + mode: FULLY_STATIC + linker_flag: "-lstdc++" + } + linking_mode_flags { + mode: MOSTLY_STATIC + linker_flag: "-l:libstdc++.a" + } + """ + + def _build_tool_path(d): """Build the list of %-escaped tool_path for the CROSSTOOL file.""" lines = [] @@ -174,7 +197,6 @@ "-std=c++0x", ] + _escaped_cplus_include_paths(repository_ctx), "linker_flag": [ - "-lstdc++", "-lm", # Some systems expect -lm in addition to -lstdc++ # Anticipated future default. ] + ( @@ -385,6 +407,7 @@ _build_tool_path(tool_paths), "%{opt_content}": _build_crosstool(opt_content, " "), "%{dbg_content}": _build_crosstool(dbg_content, " "), + "%{link_content}": _build_link_content(), "%{cxx_builtin_include_directory}": "", "%{coverage}": _coverage_feature(darwin), "%{msvc_env_tmp}": "",
diff --git a/tools/cpp/windows_cc_configure.bzl b/tools/cpp/windows_cc_configure.bzl index 6665926..7e2532b 100644 --- a/tools/cpp/windows_cc_configure.bzl +++ b/tools/cpp/windows_cc_configure.bzl
@@ -313,6 +313,7 @@ "%{content}": _get_escaped_windows_msys_crosstool_content(repository_ctx), "%{opt_content}": "", "%{dbg_content}": "", + "%{link_content}": "", "%{cxx_builtin_include_directory}": "", "%{coverage}": "", })