Switch linux RBE to ubuntu18.04, get rid of rbe_autoconfig (grpc#32559)

First step in the modernization of our RBE stack (see
go/rbe-tech-debt-notes).

- Get rid of the deprecated rbe_autoconfig and start using
[rbe_configs_gen](https://github.com/bazelbuild/bazel-toolchains#rbe_configs_gen---cli-tool-to-generate-configs)
+ check in the generated toolchain configs.
- Switch from marketplace.gcr.io/google/rbe-ubuntu16-04 to
marketplace.gcr.io/google/rbe-ubuntu18-04 (this image is still not owned
by us, but at least it's newer and demonstrates how a switch to a newer
docker image is done).
- provide script for generating the linux RBE toolchain configs.
- cleanup RBE configuration in the bazelrc files used for remote build

WORKSPACE

@@ -24,26 +24,6 @@ custom_exec_properties(
     },
 )
 
-load("@bazel_toolchains//rules:rbe_repo.bzl", "rbe_autoconfig")
-
-# Create toolchain configuration for remote execution.
-rbe_autoconfig(
-    name = "rbe_default",
-    exec_properties = create_rbe_exec_properties_dict(
-        docker_add_capabilities = "SYS_PTRACE",
-        docker_privileged = True,
-        labels = {
-            "os": "ubuntu",
-            "machine_size": "small",
-        },
-        os_family = "Linux",
-    ),
-    # use exec_properties instead of deprecated remote_execution_properties
-    use_legacy_platform_definition = False,
-)
-
-load("@bazel_toolchains//rules:environments.bzl", "clang_env")
-load("@bazel_skylib//lib:dicts.bzl", "dicts")
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 http_archive(
@@ -71,17 +51,6 @@ local_repository(
     path = "./src/core/ext/transport/binder/java",
 )
 
-# Create msan toolchain configuration for remote execution.
-rbe_autoconfig(
-    name = "rbe_msan",
-    env = dicts.add(
-        clang_env(),
-        {
-            "BAZEL_LINKOPTS": "-lc++:-lc++abi:-lm",
-        },
-    ),
-)
-
 load("@io_bazel_rules_python//python:pip.bzl", "pip_install")
 
 pip_install(

include/grpc/support/port_platform.h

@@ -776,12 +776,12 @@ extern void gpr_unreachable_code(const char* reason, const char* file,
 
 #define GRPC_CALLBACK_API_NONEXPERIMENTAL
 
-/* clang 11 with msan miscompiles destruction of [[no_unique_address]] members
- * of zero size - for a repro see:
+/* clang 12 and lower with msan miscompiles destruction of [[no_unique_address]]
+ * members of zero size - for a repro see:
  * test/core/compiler_bugs/miscompile_with_no_unique_address_test.cc
  */
 #ifdef __clang__
-#if __clang__ && __clang_major__ <= 11 && __has_feature(memory_sanitizer)
+#if __clang__ && __clang_major__ <= 12 && __has_feature(memory_sanitizer)
 #undef GPR_NO_UNIQUE_ADDRESS
 #define GPR_NO_UNIQUE_ADDRESS
 #endif

test/distrib/bazel/test_single_bazel_version.sh

@@ -36,6 +36,7 @@ EXCLUDED_TARGETS=(
   # This appears to be a legitimately broken BUILD file. There's a reference to
   # a non-existent "link_dynamic_library.sh".
   "-//third_party/toolchains/rbe_windows_bazel_5.2.0_vs2019:all"
+  "-//third_party/toolchains:rbe_windows_default_toolchain_suite"
 
   # TODO(jtattermusch): add back once fixed
   "-//examples/android/binder/..."

third_party/toolchains/BUILD

@@ -18,14 +18,52 @@ package(default_visibility = ["//visibility:public"])
 
 load("@bazel_toolchains//rules/exec_properties:exec_properties.bzl", "create_rbe_exec_properties_dict")
 
+# The default toolchain suite for RBE linux, pass it to --crosstool_top
 alias(
-    name = "rbe_windows",
-    actual = ":rbe_windows_2019",
+    name = "rbe_linux_default_toolchain_suite",
+    actual = "//third_party/toolchains/rbe_ubuntu1804/cc:toolchain",
 )
 
-# RBE Windows
+# The default CC toolchain suite for RBE linux
+alias(
+    name = "rbe_linux_default_cc_toolchain",
+    actual = "//third_party/toolchains/rbe_ubuntu1804/config:cc-toolchain",
+)
+
+# The default platform for RBE Linux
+platform(
+	name = "rbe_linux_default_platform",
+    # Inherit from the platform target generated by 'rbe_configs_gen'.
+	parents = ["//third_party/toolchains/rbe_ubuntu1804/config:platform"],
+	exec_properties = create_rbe_exec_properties_dict(
+        docker_add_capabilities = "SYS_PTRACE",
+        docker_privileged = True,
+        # by default, all RBE actions will run on "small" workers.
+        # For individual targets, this can be overridden by adding the "exec_properties = LARGE_MACHINE"
+        # attribute.
+        labels = {
+            "os": "ubuntu",
+            "machine_size": "small",
+        },
+        os_family = "Linux",
+    ),
+)
+
+# The default toolchain suite for RBE windows, pass it to --crosstool_top
+alias(
+    name = "rbe_windows_default_toolchain_suite",
+    actual = "//third_party/toolchains/rbe_windows_bazel_5.2.0_vs2019:toolchain",
+)
+
+# The default CC toolchain suite for RBE windows
+alias(
+    name = "rbe_windows_default_cc_toolchain",
+    actual = "//third_party/toolchains/rbe_windows_bazel_5.2.0_vs2019:cc-toolchain-x64_windows",
+)
+
+# The default platform for RBE windows
 platform(
-    name = "rbe_windows_2019",
+    name = "rbe_windows_default_platform",
     constraint_values = [
         "@platforms//cpu:x86_64",
         "@platforms//os:windows",
@@ -34,6 +72,7 @@ platform(
         # See rbe_win2019/Dockerfile for image details
         container_image = "docker://gcr.io/grpc-testing/rbe_windows2019@sha256:41772e8eeb9dd8c8b996bf32d58164d84b2315c8e81e634bbff5a0216b7f52fd",
         os_family = "Windows",
+        # by default, all RBE actions will run on "small" workers.
         labels = {"os": "windows_2019", "machine_size": "small"},
     ),
 )

third_party/toolchains/README.md

@@ -1,4 +1,7 @@
-# Windows RBE toolchain configuration
+# RBE toolchain configuration (Linux and Windows)
+
+- rbe_ubuntu1804: Autogenerated toolchain configuration for linux RBE.
+  Run `generate_linux_rbe_configs.sh` to regenerate.
 
 - rbe_windows_bazel_5.2.0_vs2019: The autogenerated toolchain configuration for windows RBE.
   Note that the bazel version denotes the bazel version that was used to generate the toolchain configuration. The configuration

third_party/toolchains/generate_linux_rbe_configs.sh

@@ -0,0 +1,60 @@
+#!/bin/bash
+# Copyright 2023 The gRPC Authors
+#
+# 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.
+
+# Generate linux RBE configs using rbe_configs_gen.
+# See https://github.com/bazelbuild/bazel-toolchains#rbe_configs_gen---cli-tool-to-generate-configs
+
+set -ex
+
+cd $(dirname $0)/../..
+
+REPO_ROOT="$(pwd)"
+
+TEMP_DIR="$(mktemp -d)"
+pushd "${TEMP_DIR}"
+# Build the "rbe_configs_gen" binary using the official instructions.
+git clone https://github.com/bazelbuild/bazel-toolchains.git
+cd bazel-toolchains
+# Build "rbe_configs_gen" binary under docker and put it to the current directory.
+docker run --rm -v $PWD:/srcdir -w /srcdir golang:1.16 go build -o rbe_configs_gen ./cmd/rbe_configs_gen/rbe_configs_gen.go
+popd
+
+# location of the "rbe_config_gen" binary as build by the previous step.
+RBE_CONFIGS_GEN_TOOL_PATH="${TEMP_DIR}/bazel-toolchains/rbe_configs_gen"
+
+# the container under which RBE actions will run
+LINUX_RBE_DOCKER_IMAGE=l.gcr.io/google/rbe-ubuntu18-04@sha256:48b67b41118dbcdfc265e7335f454fbefa62681ab8d47200971fc7a52fb32054
+
+# Bazel version used for configuring
+# Needs to be one of the versions from bazel/supported_versions.txt chosen so that the result is compatible
+# with other supported bazel versions.
+BAZEL_VERSION=5.4.0
+
+# TODO(jtattermusch): experiment with --cpp_env_json to simplify bazel build configuration.
+
+# Where to store the generated configs (relative to repo root)
+CONFIG_OUTPUT_PATH=third_party/toolchains/rbe_ubuntu1804
+
+# Delete old generated configs.
+rm -rf "${REPO_ROOT}/${CONFIG_OUTPUT_PATH}"
+
+${RBE_CONFIGS_GEN_TOOL_PATH} \
+    --bazel_version="${BAZEL_VERSION}" \
+    --toolchain_container="${LINUX_RBE_DOCKER_IMAGE}" \
+    --output_src_root="${REPO_ROOT}" \
+    --output_config_path="${CONFIG_OUTPUT_PATH}" \
+    --exec_os=linux \
+    --target_os=linux \
+    --generate_java_configs=false