Add Linaro ARM Linux cross compiling toolchain

.gitlab-ci.yml

@@ -73,6 +73,7 @@ platform_compatible_tests:
   stage: platform_compatible_tests
   script:
     - bazel build mace/core:core --define openmp=true
+    - bazel build --config aarch64_linux --define openmp=true --define opencl=true --define neon=true //mace/libmace:libmace.so
 
 build_libraries:
   stage: build_libraries

WORKSPACE

@@ -4,8 +4,9 @@ workspace(name = "mace")
 load("//repository/git:git_configure.bzl", "git_version_repository")
 load("//repository/opencl-kernel:opencl_kernel_configure.bzl", "encrypt_opencl_kernel_repository")
 
-git_version_repository(name="local_version_config")
-encrypt_opencl_kernel_repository(name="local_opencl_kernel_encrypt")
+git_version_repository(name = "local_version_config")
+
+encrypt_opencl_kernel_repository(name = "local_opencl_kernel_encrypt")
 
 # proto_library rules implicitly depend on @com_google_protobuf//:protoc,
 # which is the proto-compiler.
@@ -138,3 +139,26 @@ android_ndk_repository(
     # Android 5.0
     api_level = 21,
 )
+
+# Set up default cross compilers for arm linux
+new_http_archive(
+    name = "gcc_linaro_7_3_1_arm_linux_gnueabihf",
+    build_file = "third_party/compilers/arm_compiler.BUILD",
+    sha256 = "7248bf105d0d468887a9b8a7120bb281ac8ad0223d9cb3d00dc7c2d498485d91",
+    strip_prefix = "gcc-linaro-7.3.1-2018.05-x86_64_arm-linux-gnueabihf",
+    urls = [
+        "https://cnbj1.fds.api.xiaomi.com/mace/third-party/gcc-linaro/gcc-linaro-7.3.1-2018.05-x86_64_arm-linux-gnueabihf.tar.xz",
+        "https://releases.linaro.org/components/toolchain/binaries/latest/arm-linux-gnueabihf/gcc-linaro-7.3.1-2018.05-x86_64_arm-linux-gnueabihf.tar.xz",
+    ],
+)
+
+new_http_archive(
+    name = "gcc_linaro_7_3_1_aarch64_linux_gnu",
+    build_file = "third_party/compilers/aarch64_compiler.BUILD",
+    sha256 = "73eed74e593e2267504efbcf3678918bb22409ab7afa3dc7c135d2c6790c2345",
+    strip_prefix = "gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu",
+    urls = [
+        "https://cnbj1.fds.api.xiaomi.com/mace/third-party/gcc-linaro/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu.tar.xz",
+        "https://releases.linaro.org/components/toolchain/binaries/latest/aarch64-linux-gnu/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu.tar.xz",
+    ],
+)

mace/core/BUILD

@@ -104,7 +104,7 @@ cc_library(
         "-Werror",
         "-Wextra",
         "-Wno-missing-field-initializers",
-    ] + if_opencl_enabled([
+    ] + if_openmp_enabled(["-fopenmp"]) + if_opencl_enabled([
         "-DMACE_ENABLE_OPENCL",
     ]),
     deps = [

mace/core/testing/test_benchmark.cc

@@ -53,7 +53,6 @@ void Benchmark::Run(const char *pattern) {
 
   // Compute name width.
   int width = 10;
-  char name[100];
   std::smatch match;
   for (auto b : *all_benchmarks) {
     if (!std::regex_match(b->name_, match, regex)) continue;

mace/kernels/sgemm.cc

@@ -811,7 +811,7 @@ void SGemm::RunPerBatch(const float *lhs_data,
       // d: remain
       for (index_t d = 0; d < remain_d; ++d) {
         // 4.1.1
-        float32x4_t b0, b1;
+        float32x4_t b0;
         float32x2_t a0 = vdup_n_f32(rhs_ptr[0]);
 
         b0 = vld1q_f32(lhs_ptr);

mace/ops/deconv_2d_test.cc

@@ -291,7 +291,6 @@ void TestComplexDeconvNxNS12(const int batch,
   auto func = [&](int kernel_h, int kernel_w, int stride_h, int stride_w,
                   Padding type, int padding) {
     // generate random input
-    static unsigned int seed = time(NULL);
     int height = shape[0];
     int width = shape[1];
     int input_channels = shape[2];

mace/ops/ops_test_util.h

@@ -245,7 +245,6 @@ class OpsTestNet {
     output->Resize(input_shape);
 
     Tensor::MappingGuard input_guard(input);
-    const T *input_data = input->data<T>();
     output->CopyBytes(input->raw_data(), input->size() * input->SizeOfType());
   }
 

mace/ops/quantize_test.cc

@@ -54,8 +54,6 @@ void TestQuantizeDequantize(const std::vector<float> &input, bool non_zero) {
 
   net.RunOp();
 
-  auto output = net.GetTensor("Output");
-
   ExpectTensorNear<float>(*net.GetTensor("Input"),
                           *net.GetTensor("Output"),
                           0.1);

third_party/compilers/aarch64_compiler.BUILD

+package(default_visibility = ['//visibility:public'])
+
+filegroup(
+  name = 'gcc',
+  srcs = [
+    'bin/aarch64-linux-gnu-gcc',
+  ],
+)
+
+filegroup(
+  name = 'ar',
+  srcs = [
+    'bin/aarch64-linux-gnu-ar',
+  ],
+)
+
+filegroup(
+  name = 'ld',
+  srcs = [
+    'bin/aarch64-linux-gnu-ld',
+  ],
+)
+
+filegroup(
+  name = 'nm',
+  srcs = [
+    'bin/aarch64-linux-gnu-nm',
+  ],
+)
+
+filegroup(
+  name = 'objcopy',
+  srcs = [
+    'bin/aarch64-linux-gnu-objcopy',
+  ],
+)
+
+filegroup(
+  name = 'objdump',
+  srcs = [
+    'bin/aarch64-linux-gnu-objdump',
+  ],
+)
+
+filegroup(
+  name = 'strip',
+  srcs = [
+    'bin/aarch64-linux-gnu-strip',
+  ],
+)
+
+filegroup(
+  name = 'as',
+  srcs = [
+    'bin/aarch64-linux-gnu-as',
+  ],
+)
+
+filegroup(
+    name = "compiler_pieces",
+    srcs = glob([
+        "aarch64-linux-gnu/**",
+        "libexec/**",
+        "lib/gcc/aarch64-linux-gnu/**",
+        "include/**",
+    ]),
+)
+
+filegroup(
+    name = "compiler_components",
+    srcs = [
+        ":ar",
+        ":as",
+        ":gcc",
+        ":ld",
+        ":nm",
+        ":objcopy",
+        ":objdump",
+        ":strip",
+    ],
+)

third_party/compilers/arm_compiler.BUILD

+package(default_visibility = ["//visibility:public"])
+
+filegroup(
+    name = "gcc",
+    srcs = [
+        "bin/arm-linux-gnueabihf-gcc",
+    ],
+)
+
+filegroup(
+    name = "ar",
+    srcs = [
+        "bin/arm-linux-gnueabihf-ar",
+    ],
+)
+
+filegroup(
+    name = "ld",
+    srcs = [
+        "bin/arm-linux-gnueabihf-ld",
+    ],
+)
+
+filegroup(
+    name = "nm",
+    srcs = [
+        "bin/arm-linux-gnueabihf-nm",
+    ],
+)
+
+filegroup(
+    name = "objcopy",
+    srcs = [
+        "bin/arm-linux-gnueabihf-objcopy",
+    ],
+)
+
+filegroup(
+    name = "objdump",
+    srcs = [
+        "bin/arm-linux-gnueabihf-objdump",
+    ],
+)
+
+filegroup(
+    name = "strip",
+    srcs = [
+        "bin/arm-linux-gnueabihf-strip",
+    ],
+)
+
+filegroup(
+    name = "as",
+    srcs = [
+        "bin/arm-linux-gnueabihf-as",
+    ],
+)
+
+filegroup(
+    name = "compiler_pieces",
+    srcs = glob([
+        "arm-linux-gnueabihf/**",
+        "libexec/**",
+        "lib/gcc/arm-linux-gnueabihf/**",
+        "include/**",
+    ]),
+)
+
+filegroup(
+    name = "compiler_components",
+    srcs = [
+        ":ar",
+        ":as",
+        ":gcc",
+        ":ld",
+        ":nm",
+        ":objcopy",
+        ":objdump",
+        ":strip",
+    ],
+)

tools/aarch64_compiler/BUILD

+# This is the entry point for --crosstool_top.  Toolchains are found
+# by lopping off the name of --crosstool_top and searching for
+# 'cc-compiler-${CPU}' in this BUILD file, where CPU is the target CPU
+# specified in --cpu.
+#
+# This file group should include
+#   * all cc_toolchain targets supported
+#   * all file groups that said cc_toolchain might refer to,
+# including the default_grte_top setting in the CROSSTOOL
+# protobuf.
+filegroup(
+    name = "toolchain_fg",
+    srcs = [
+        ":cc-compiler-aarch64",
+        ":linaro_linux_all_files",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:compiler_components",
+    ],
+)
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]) + [
+        "//tools/aarch64_compiler/linaro_linux_gcc:srcs",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_toolchain_suite(
+    name = "toolchain",
+    # target_cpu | compiler
+    toolchains = {
+        "aarch64|gcc": "cc-compiler-aarch64",
+    },
+)
+
+filegroup(
+    name = "linaro_linux_all_files",
+    srcs = [
+        "//tools/aarch64_compiler/linaro_linux_gcc:tool-wrappers",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:compiler_pieces",
+    ],
+)
+
+filegroup(
+    name = "linaro_linux_linker_files",
+    srcs = [
+        "//tools/aarch64_compiler/linaro_linux_gcc:ar",
+        "//tools/aarch64_compiler/linaro_linux_gcc:gcc",
+        "//tools/aarch64_compiler/linaro_linux_gcc:ld",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:compiler_pieces",
+    ],
+)
+
+filegroup(
+    name = "linaro_linux_compiler_files",
+    srcs = [
+        "//tools/aarch64_compiler/linaro_linux_gcc:as",
+        "//tools/aarch64_compiler/linaro_linux_gcc:gcc",
+        "//tools/aarch64_compiler/linaro_linux_gcc:ld",
+    ],
+)
+
+filegroup(
+    name = "empty",
+    srcs = [],
+)
+
+cc_toolchain(
+    name = "cc-compiler-aarch64",
+    all_files = ":linaro_linux_all_files",
+    compiler_files = ":linaro_linux_compiler_files",
+    cpu = "aarch64",
+    dwp_files = ":empty",
+    dynamic_runtime_libs = [":empty"],
+    linker_files = ":linaro_linux_linker_files",
+    objcopy_files = "//tools/aarch64_compiler/linaro_linux_gcc:objcopy",
+    static_runtime_libs = [":empty"],
+    strip_files = "//tools/aarch64_compiler/linaro_linux_gcc:strip",
+    supports_param_files = 1,
+    visibility = ["//visibility:public"],
+)

tools/aarch64_compiler/CROSSTOOL

+major_version: "local"
+minor_version: ""
+default_target_cpu: "aarch64"
+
+default_toolchain {
+  cpu: "aarch64"
+  toolchain_identifier: "aarch64-linux-gnu"
+}
+
+toolchain {
+  abi_version: "gcc"
+  abi_libc_version: ""
+  builtin_sysroot: ""
+  compiler: "gcc"
+  host_system_name: "aarch64"
+  needsPic: true
+  supports_gold_linker: false
+  supports_incremental_linker: false
+  supports_fission: false
+  supports_interface_shared_objects: false
+  supports_normalizing_ar: true
+  supports_start_end_lib: false
+  supports_thin_archives: true
+  target_libc: ""
+  target_cpu: "aarch64"
+  target_system_name: ""
+  toolchain_identifier: "aarch64-linux-gnu"
+
+  tool_path { name: "ar" path: "linaro_linux_gcc/aarch64-linux-gnu-ar" }
+  tool_path { name: "compat-ld" path: "linaro_linux_gcc/aarch64-linux-gnu-ld" }
+  tool_path { name: "cpp" path: "linaro_linux_gcc/aarch64-linux-gnu-gcc" }
+  tool_path { name: "dwp" path: "linaro_linux_gcc/aarch64-linux-gnu-dwp" }
+  tool_path { name: "gcc" path: "linaro_linux_gcc/aarch64-linux-gnu-gcc" }
+  tool_path { name: "gcov" path: "linaro_linux_gcc/aarch64-linux-gnu-gcov" }
+  # C(++) compiles invoke the compiler (as that is the one knowing where
+  # to find libraries), but we provide LD so other rules can invoke the linker.
+  tool_path { name: "ld" path: "linaro_linux_gcc/aarch64-linux-gnu-ld" }
+  tool_path { name: "nm" path: "linaro_linux_gcc/aarch64-linux-gnu-nm" }
+  tool_path { name: "objcopy" path: "linaro_linux_gcc/aarch64-linux-gnu-objcopy" }
+  objcopy_embed_flag: "-I"
+  objcopy_embed_flag: "binary"
+  tool_path { name: "objdump" path: "linaro_linux_gcc/aarch64-linux-gnu-objdump" }
+  tool_path { name: "strip" path: "linaro_linux_gcc/aarch64-linux-gnu-strip" }
+
+  compiler_flag: "--sysroot=external/gcc_linaro_7_3_1_aarch64_linux_gnu/aarch64-linux-gnu/libc"
+
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_aarch64_linux_gnu/aarch64-linux-gnu/include/c++/7.3.1/aarch64-linux-gnu"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_aarch64_linux_gnu/aarch64-linux-gnu/include/c++/7.3.1"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_aarch64_linux_gnu/include/c++/7.3.1/aarch64-linux-gnu"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_aarch64_linux_gnu/include/c++/7.3.1"
+
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/libc/usr/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/libc/usr/lib/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/libc/lib/gcc/aarch64-linux-gnu/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//include)%/c++/7.3.1"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/libc/lib/gcc/aarch64-linux-gnu/7.3.1/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/libc/lib/gcc/aarch64-linux-gnu/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//lib/gcc/aarch64-linux-gnu/7.3.1/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//lib/gcc/aarch64-linux-gnu/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_aarch64_linux_gnu//aarch64-linux-gnu/include)%/c++/7.3.1"
+
+  linker_flag: "--sysroot=external/gcc_linaro_7_3_1_aarch64_linux_gnu/aarch64-linux-gnu/libc"
+  linker_flag: "-fuse-ld=gold"
+  linker_flag: "-Wl,-no-as-needed"
+  linker_flag: "-lstdc++"
+  linker_flag: "-latomic"
+  linker_flag: "-lm"
+  linker_flag: "-lpthread"
+
+  # Anticipated future default.
+  # This makes GCC and Clang do what we want when called through symlinks.
+  unfiltered_cxx_flag: "-no-canonical-prefixes"
+  linker_flag: "-no-canonical-prefixes"
+
+  # Make C++ compilation deterministic. Use linkstamping instead of these
+  # compiler symbols.
+  unfiltered_cxx_flag: "-Wno-builtin-macro-redefined"
+  unfiltered_cxx_flag: "-D__DATE__=\"redacted\""
+  unfiltered_cxx_flag: "-D__TIMESTAMP__=\"redacted\""
+  unfiltered_cxx_flag: "-D__TIME__=\"redacted\""
+
+  # Security hardening on by default.
+  # Conservative choice; -D_FORTIFY_SOURCE=2 may be unsafe in some cases.
+  # We need to undef it before redefining it as some distributions now have
+  # it enabled by default.
+  compiler_flag: "-U_FORTIFY_SOURCE"
+  compiler_flag: "-fstack-protector"
+  compiler_flag: "-fPIE"
+  linker_flag: "-v"
+  linker_flag: "-pie"
+  linker_flag: "-Wl,-z,relro,-z,now"
+
+  # Enable coloring even if there's no attached terminal. Bazel removes the
+  # escape sequences if --nocolor is specified.
+  compiler_flag: "-fdiagnostics-color=always"
+
+  # All warnings are enabled. Maybe enable -Werror as well?
+  compiler_flag: "-Wall"
+  # Enable a few more warnings that aren't part of -Wall.
+  compiler_flag: "-Wunused-but-set-parameter"
+  # But disable some that are problematic.
+  compiler_flag: "-Wno-free-nonheap-object" # has false positives
+
+  # Keep stack frames for debugging, even in opt mode.
+  compiler_flag: "-fno-omit-frame-pointer"
+
+  # Stamp the binary with a unique identifier.
+  linker_flag: "-Wl,--build-id=md5"
+  linker_flag: "-Wl,--hash-style=gnu"
+
+  compilation_mode_flags {
+    mode: DBG
+    # Enable debug symbols.
+    compiler_flag: "-g"
+  }
+  compilation_mode_flags {
+    mode: OPT
+    # No debug symbols.
+    # Maybe we should enable https://gcc.gnu.org/wiki/DebugFission for opt or
+    # even generally? However, that can't happen here, as it requires special
+    # handling in Bazel.
+    compiler_flag: "-g0"
+
+    # Conservative choice for -O
+    # -O3 can increase binary size and even slow down the resulting binaries.
+    # Profile first and / or use FDO if you need better performance than this.
+    compiler_flag: "-O2"
+
+    # Disable assertions
+    compiler_flag: "-DNDEBUG"
+
+    # Removal of unused code and data at link time (can this increase binary size in some cases?).
+    compiler_flag: "-ffunction-sections"
+    compiler_flag: "-fdata-sections"
+    linker_flag: "-Wl,--gc-sections"
+  }
+}

tools/aarch64_compiler/linaro_linux_gcc/BUILD

+package(default_visibility = ["//tools/aarch64_compiler:__pkg__"])
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]),
+    visibility = ["//visibility:public"],
+)
+
+filegroup(
+    name = "gcc",
+    srcs = [
+        "aarch64-linux-gnu-gcc",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:gcc",
+    ],
+)
+
+filegroup(
+    name = "ar",
+    srcs = [
+        "aarch64-linux-gnu-ar",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:ar",
+    ],
+)
+
+filegroup(
+    name = "ld",
+    srcs = [
+        "aarch64-linux-gnu-ld",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:ld",
+    ],
+)
+
+filegroup(
+    name = "nm",
+    srcs = [
+        "aarch64-linux-gnu-nm",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:nm",
+    ],
+)
+
+filegroup(
+    name = "objcopy",
+    srcs = [
+        "aarch64-linux-gnu-objcopy",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:objcopy",
+    ],
+)
+
+filegroup(
+    name = "objdump",
+    srcs = [
+        "aarch64-linux-gnu-objdump",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:objdump",
+    ],
+)
+
+filegroup(
+    name = "strip",
+    srcs = [
+        "aarch64-linux-gnu-strip",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:strip",
+    ],
+)
+
+filegroup(
+    name = "as",
+    srcs = [
+        "aarch64-linux-gnu-as",
+        "@gcc_linaro_7_3_1_aarch64_linux_gnu//:as",
+    ],
+)
+
+filegroup(
+    name = "tool-wrappers",
+    srcs = [
+        ":ar",
+        ":as",
+        ":gcc",
+        ":ld",
+        ":nm",
+        ":objcopy",
+        ":objdump",
+        ":strip",
+    ],
+)

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-ar

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-ar \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-ar \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-as

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-as \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-as \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-gcc

+#!/bin/bash --norc
+
+PATH="external/gcc_linaro_7_3_1_aarch64_linux_gnu/libexec/gcc/aarch64-linux-gnu/7.3.1:$PATH" \
+    exec \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-gcc \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-gcov

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-gcov \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-gcov \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-ld

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-ld \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-ld \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-nm

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-nm \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-nm \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-objcopy

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-objcopy \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-objcopy \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-objdump

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-objdump \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-objdump \
+    "$@"

tools/aarch64_compiler/linaro_linux_gcc/aarch64-linux-gnu-strip

+#!/bin/bash --norc
+
+exec -a aarch64-linux-gnu-strip \
+    external/gcc_linaro_7_3_1_aarch64_linux_gnu/bin/aarch64-linux-gnu-strip \
+    "$@"

tools/arm_compiler/BUILD

+# This is the entry point for --crosstool_top.  Toolchains are found
+# by lopping off the name of --crosstool_top and searching for
+# 'cc-compiler-${CPU}' in this BUILD file, where CPU is the target CPU
+# specified in --cpu.
+#
+# This file group should include
+#   * all cc_toolchain targets supported
+#   * all file groups that said cc_toolchain might refer to,
+# including the default_grte_top setting in the CROSSTOOL
+# protobuf.
+filegroup(
+    name = "toolchain_fg",
+    srcs = [
+        ":cc-compiler-armeabi-v7a",
+        ":linaro_linux_all_files",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:compiler_components",
+    ],
+)
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]) + [
+        "//tools/arm_compiler/linaro_linux_gcc:srcs",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+cc_toolchain_suite(
+    name = "toolchain",
+    # target_cpu | compiler
+    toolchains = {
+        "armeabi-v7a|gcc": "cc-compiler-armeabi-v7a",
+    },
+)
+
+filegroup(
+    name = "linaro_linux_all_files",
+    srcs = [
+        "//tools/arm_compiler/linaro_linux_gcc:tool-wrappers",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:compiler_pieces",
+    ],
+)
+
+filegroup(
+    name = "linaro_linux_linker_files",
+    srcs = [
+        "//tools/arm_compiler/linaro_linux_gcc:ar",
+        "//tools/arm_compiler/linaro_linux_gcc:gcc",
+        "//tools/arm_compiler/linaro_linux_gcc:ld",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:compiler_pieces",
+    ],
+)
+
+filegroup(
+    name = "linaro_linux_compiler_files",
+    srcs = [
+        "//tools/arm_compiler/linaro_linux_gcc:as",
+        "//tools/arm_compiler/linaro_linux_gcc:gcc",
+        "//tools/arm_compiler/linaro_linux_gcc:ld",
+    ],
+)
+
+filegroup(
+    name = "empty",
+    srcs = [],
+)
+
+cc_toolchain(
+    name = "cc-compiler-armeabi-v7a",
+    all_files = ":linaro_linux_all_files",
+    compiler_files = ":linaro_linux_compiler_files",
+    cpu = "armeabi-v7a",
+    dwp_files = ":empty",
+    dynamic_runtime_libs = [":empty"],
+    linker_files = ":linaro_linux_linker_files",
+    objcopy_files = "//tools/arm_compiler/linaro_linux_gcc:objcopy",
+    static_runtime_libs = [":empty"],
+    strip_files = "//tools/arm_compiler/linaro_linux_gcc:strip",
+    supports_param_files = 1,
+    visibility = ["//visibility:public"],
+)

tools/arm_compiler/CROSSTOOL

+major_version: "local"
+minor_version: ""
+default_target_cpu: "armeabi-v7a"
+
+default_toolchain {
+  cpu: "armeabi-v7a"
+  toolchain_identifier: "arm-linux-gnueabihf"
+}
+
+toolchain {
+  abi_version: "gcc"
+  abi_libc_version: ""
+  builtin_sysroot: ""
+  compiler: "gcc"
+  host_system_name: "armeabi-v7a"
+  needsPic: true
+  supports_gold_linker: false
+  supports_incremental_linker: false
+  supports_fission: false
+  supports_interface_shared_objects: false
+  supports_normalizing_ar: true
+  supports_start_end_lib: false
+  supports_thin_archives: true
+  target_libc: ""
+  target_cpu: "armeabi-v7a"
+  target_system_name: ""
+  toolchain_identifier: "arm-linux-gnueabihf"
+
+  tool_path { name: "ar" path: "linaro_linux_gcc/arm-linux-gnueabihf-ar" }
+  tool_path { name: "compat-ld" path: "linaro_linux_gcc/arm-linux-gnueabihf-ld" }
+  tool_path { name: "cpp" path: "linaro_linux_gcc/arm-linux-gnueabihf-gcc" }
+  tool_path { name: "dwp" path: "linaro_linux_gcc/arm-linux-gnueabihf-dwp" }
+  tool_path { name: "gcc" path: "linaro_linux_gcc/arm-linux-gnueabihf-gcc" }
+  tool_path { name: "gcov" path: "linaro_linux_gcc/arm-linux-gnueabihf-gcov" }
+  # C(++) compiles invoke the compiler (as that is the one knowing where
+  # to find libraries), but we provide LD so other rules can invoke the linker.
+  tool_path { name: "ld" path: "linaro_linux_gcc/arm-linux-gnueabihf-ld" }
+  tool_path { name: "nm" path: "linaro_linux_gcc/arm-linux-gnueabihf-nm" }
+  tool_path { name: "objcopy" path: "linaro_linux_gcc/arm-linux-gnueabihf-objcopy" }
+  objcopy_embed_flag: "-I"
+  objcopy_embed_flag: "binary"
+  tool_path { name: "objdump" path: "linaro_linux_gcc/arm-linux-gnueabihf-objdump" }
+  tool_path { name: "strip" path: "linaro_linux_gcc/arm-linux-gnueabihf-strip" }
+
+  compiler_flag: "--sysroot=external/gcc_linaro_7_3_1_arm_linux_gnueabihf/arm-linux-gnueabihf/libc"
+
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_arm_linux_gnueabihf/arm-linux-gnueabihf/include/c++/7.3.1/arm-linux-gnueabihf"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_arm_linux_gnueabihf/arm-linux-gnueabihf/include/c++/7.3.1"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_arm_linux_gnueabihf/include/c++/7.3.1/arm-linux-gnueabihf"
+  cxx_flag: "-isystem"
+  cxx_flag: "external/gcc_linaro_7_3_1_arm_linux_gnueabihf/include/c++/7.3.1"
+
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/libc/usr/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/libc/usr/lib/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//include)%/c++/7.3.1"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.3.1/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/libc/lib/gcc/arm-linux-gnueabihf/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//lib/gcc/arm-linux-gnueabihf/7.3.1/include)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//lib/gcc/arm-linux-gnueabihf/7.3.1/include-fixed)%"
+  cxx_builtin_include_directory: "%package(@gcc_linaro_7_3_1_arm_linux_gnueabihf//arm-linux-gnueabihf/include)%/c++/7.3.1"
+
+  linker_flag: "--sysroot=external/gcc_linaro_7_3_1_arm_linux_gnueabihf/arm-linux-gnueabihf/libc"
+  linker_flag: "-fuse-ld=gold"
+  linker_flag: "-Wl,-no-as-needed"
+  linker_flag: "-lstdc++"
+  linker_flag: "-latomic"
+  linker_flag: "-lm"
+  linker_flag: "-lpthread"
+
+  # Anticipated future default.
+  # This makes GCC and Clang do what we want when called through symlinks.
+  unfiltered_cxx_flag: "-no-canonical-prefixes"
+  linker_flag: "-no-canonical-prefixes"
+
+  # Make C++ compilation deterministic. Use linkstamping instead of these
+  # compiler symbols.
+  unfiltered_cxx_flag: "-Wno-builtin-macro-redefined"
+  unfiltered_cxx_flag: "-D__DATE__=\"redacted\""
+  unfiltered_cxx_flag: "-D__TIMESTAMP__=\"redacted\""
+  unfiltered_cxx_flag: "-D__TIME__=\"redacted\""
+
+  # Security hardening on by default.
+  # Conservative choice; -D_FORTIFY_SOURCE=2 may be unsafe in some cases.
+  # We need to undef it before redefining it as some distributions now have
+  # it enabled by default.
+  compiler_flag: "-U_FORTIFY_SOURCE"
+  compiler_flag: "-fstack-protector"
+  compiler_flag: "-fPIE"
+  linker_flag: "-v"
+  linker_flag: "-pie"
+  linker_flag: "-Wl,-z,relro,-z,now"
+
+  # Enable coloring even if there's no attached terminal. Bazel removes the
+  # escape sequences if --nocolor is specified.
+  compiler_flag: "-fdiagnostics-color=always"
+
+  # All warnings are enabled. Maybe enable -Werror as well?
+  compiler_flag: "-Wall"
+  # Enable a few more warnings that aren't part of -Wall.
+  compiler_flag: "-Wunused-but-set-parameter"
+  # But disable some that are problematic.
+  compiler_flag: "-Wno-free-nonheap-object" # has false positives
+
+  # Keep stack frames for debugging, even in opt mode.
+  compiler_flag: "-fno-omit-frame-pointer"
+
+  # Stamp the binary with a unique identifier.
+  linker_flag: "-Wl,--build-id=md5"
+  linker_flag: "-Wl,--hash-style=gnu"
+
+  compilation_mode_flags {
+    mode: DBG
+    # Enable debug symbols.
+    compiler_flag: "-g"
+  }
+  compilation_mode_flags {
+    mode: OPT
+    # No debug symbols.
+    # Maybe we should enable https://gcc.gnu.org/wiki/DebugFission for opt or
+    # even generally? However, that can't happen here, as it requires special
+    # handling in Bazel.
+    compiler_flag: "-g0"
+
+    # Conservative choice for -O
+    # -O3 can increase binary size and even slow down the resulting binaries.
+    # Profile first and / or use FDO if you need better performance than this.
+    compiler_flag: "-O2"
+
+    # Disable assertions
+    compiler_flag: "-DNDEBUG"
+
+    # Removal of unused code and data at link time (can this increase binary size in some cases?).
+    compiler_flag: "-ffunction-sections"
+    compiler_flag: "-fdata-sections"
+    linker_flag: "-Wl,--gc-sections"
+  }
+}

tools/arm_compiler/linaro_linux_gcc/BUILD

+package(default_visibility = ["//tools/arm_compiler:__pkg__"])
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]),
+    visibility = ["//visibility:public"],
+)
+
+filegroup(
+    name = "gcc",
+    srcs = [
+        "arm-linux-gnueabihf-gcc",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:gcc",
+    ],
+)
+
+filegroup(
+    name = "ar",
+    srcs = [
+        "arm-linux-gnueabihf-ar",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:ar",
+    ],
+)
+
+filegroup(
+    name = "ld",
+    srcs = [
+        "arm-linux-gnueabihf-ld",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:ld",
+    ],
+)
+
+filegroup(
+    name = "nm",
+    srcs = [
+        "arm-linux-gnueabihf-nm",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:nm",
+    ],
+)
+
+filegroup(
+    name = "objcopy",
+    srcs = [
+        "arm-linux-gnueabihf-objcopy",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:objcopy",
+    ],
+)
+
+filegroup(
+    name = "objdump",
+    srcs = [
+        "arm-linux-gnueabihf-objdump",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:objdump",
+    ],
+)
+
+filegroup(
+    name = "strip",
+    srcs = [
+        "arm-linux-gnueabihf-strip",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:strip",
+    ],
+)
+
+filegroup(
+    name = "as",
+    srcs = [
+        "arm-linux-gnueabihf-as",
+        "@gcc_linaro_7_3_1_arm_linux_gnueabihf//:as",
+    ],
+)
+
+filegroup(
+    name = "tool-wrappers",
+    srcs = [
+        ":ar",
+        ":as",
+        ":gcc",
+        ":ld",
+        ":nm",
+        ":objcopy",
+        ":objdump",
+        ":strip",
+    ],
+)

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-ar

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-ar \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-ar \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-as

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-as \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-as \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-gcc

+#!/bin/bash --norc
+
+PATH="external/gcc_linaro_7_3_1_arm_linux_gnueabihf/libexec/gcc/arm-linux-gnueabihf/7.3.1:$PATH" \
+    exec \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-gcc \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-gcov

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-gcov \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-gcov \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-ld

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-ld \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-ld \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-nm

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-nm \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-nm \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-objcopy

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-objcopy \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-objcopy \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-objdump

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-objdump \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-objdump \
+    "$@"

tools/arm_compiler/linaro_linux_gcc/arm-linux-gnueabihf-strip

+#!/bin/bash --norc
+
+exec -a arm-linux-gnueabihf-strip \
+    external/gcc_linaro_7_3_1_arm_linux_gnueabihf/bin/arm-linux-gnueabihf-strip \
+    "$@"

tools/bazel.rc

@@ -17,9 +17,31 @@ build --copt=-DMACE_USE_NNLIB_CAF
 build:symbol_hidden --copt=-fvisibility=hidden
 
 # Usage example: bazel build --config android
+build:android --config=cross_compile
 build:android --crosstool_top=//external:android/crosstool
 build:android --host_crosstool_top=@bazel_tools//tools/cpp:toolchain
-build:android --config=cross_compile
+
+# Usage example: bazel build --config arm_linux
+build:arm_linux --config=cross_compile
+build:arm_linux --crosstool_top=//tools/arm_compiler:toolchain
+build:arm_linux --host_crosstool_top=@bazel_tools//tools/cpp:toolchain
+build:arm_linux --cpu=armeabi-v7a
+build:arm_linux --copt -mfloat-abi=hard
+build:arm_linux --copt -mfpu=neon 
+build:arm_linux --copt -Wno-ignored-attributes
+build:arm_linux --copt -Wno-unused-function
+build:arm_linux --copt -Wno-sequence-point
+build:arm_linux --copt -Wno-implicit-fallthrough
+
+# Usage example: bazel build --config aarch64_linux
+build:aarch64_linux --config=cross_compile
+build:aarch64_linux --crosstool_top=//tools/aarch64_compiler:toolchain
+build:aarch64_linux --host_crosstool_top=@bazel_tools//tools/cpp:toolchain
+build:aarch64_linux --cpu=aarch64
+build:aarch64_linux --copt -Wno-ignored-attributes
+build:aarch64_linux --copt -Wno-unused-function
+build:aarch64_linux --copt -Wno-sequence-point
+build:aarch64_linux --copt -Wno-implicit-fallthrough
 
 # Usage example: bazel build --config optimization 
 build:optimization -c opt