gn/BUILD.gn

# Copyright 2016 Google Inc.
#
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

declare_args() {
  cc = "cc"
  cxx = "c++"

  if (is_android) {
    cc = "$ndk/toolchains/llvm/prebuilt/$ndk_host/bin/clang"
    cxx = "$ndk/toolchains/llvm/prebuilt/$ndk_host/bin/clang++"
  }

  extra_cflags = ""
  extra_cflags_c = ""
  extra_cflags_cc = ""
}

config("no_rtti") {
  cflags_cc = [ "-fno-rtti" ]
}

config("default") {
  cflags = [
    "-g",
    "-fstrict-aliasing",
    "-fPIC",
    "-fvisibility=hidden",

    "-Werror",
    "-Wall",
    "-Wextra",
    "-Winit-self",
    "-Wpointer-arith",
    "-Wsign-compare",
    "-Wvla",

    "-Wno-deprecated-declarations",
    "-Wno-unused-parameter",
  ]
  cflags_cc = [
    "-std=c++11",
    "-fno-exceptions",
    "-fno-threadsafe-statics",
    "-fvisibility-inlines-hidden",

    "-Wnon-virtual-dtor",
  ]
  if (current_cpu == "arm") {
    cflags += [ "-mfpu=neon" ]
  }

  if (is_android) {
    asmflags = [ "--target=$ndk_target" ]
    cflags += [
      "--sysroot=$ndk/platforms/$ndk_platform",
      "--target=$ndk_target",
    ]
    cflags_cc += [
      "-isystem$ndk/sources/android/support/include",
      "-isystem$ndk/sources/cxx-stl/llvm-libc++/libcxx/include",
    ]
    ldflags = [
      "--sysroot=$ndk/platforms/$ndk_platform",
      "--target=$ndk_target",
      "-B$ndk/toolchains/$ndk_target-4.9/prebuilt/$ndk_host/$ndk_target/bin",
      "-pie",
    ]
    lib_dirs = [
      "$ndk/sources/cxx-stl/llvm-libc++/libs/$ndk_stdlib",
      "$ndk/toolchains/$ndk_target-4.9/prebuilt/$ndk_host/lib/gcc/$ndk_target/4.9.x",
    ]
    libs = [
      # Order matters here!  Keep these three in exactly this order.
      "c++_static",
      "c++abi",
      "android_support",
    ]
  }

  if (is_linux) {
    libs = [ "pthread" ]
  }
}

config("release") {
  cflags = [ "-Os" ]
  defines = [ "NDEBUG" ]
}

config("executable") {
  if (is_mac) {
    ldflags = [ "-Wl,-rpath,@loader_path/." ]
  } else if (is_linux) {
    ldflags = [ "-Wl,-rpath,\$ORIGIN" ]
  }
}

pool("link_pool") {
  depth = 0  #unlimited
}

toolchain("gcc_like") {
  lib_switch = "-l"
  lib_dir_switch = "-L"

  tool("cc") {
    depfile = "{{output}}.d"
    command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} $extra_cflags $extra_cflags_c -c {{source}} -o {{output}}"
    depsformat = "gcc"
    outputs = [
      "{{source_out_dir}}/{{target_output_name}}.{{source_name_part}}.o",
    ]
    description = "$cc ... $extra_cflags $extra_cflags_c -o {{output}}"
  }

  tool("cxx") {
    depfile = "{{output}}.d"
    command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} {{cflags}} {{cflags_cc}} $extra_cflags $extra_cflags_cc -c {{source}} -o {{output}}"
    depsformat = "gcc"
    outputs = [
      "{{source_out_dir}}/{{target_output_name}}.{{source_name_part}}.o",
    ]
    description = "$cxx ... $extra_cflags $extra_cflags_cc -o {{output}}"
  }

  tool("asm") {
    depfile = "{{output}}.d"
    command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} {{asmflags}} -c {{source}} -o {{output}}"
    depsformat = "gcc"
    outputs = [
      "{{source_out_dir}}/{{target_output_name}}.{{source_name_part}}.o",
    ]
    description = "$cc ... -o {{output}}"
  }

  tool("alink") {
    command = "rm -f {{output}} && ar rcs {{output}} {{inputs}}"
    outputs = [
      "{{root_out_dir}}/{{target_output_name}}{{output_extension}}",
    ]
    default_output_extension = ".a"
    output_prefix = "lib"
    description = "ar {{output}} ..."
  }

  tool("solink") {
    soname = "{{target_output_name}}{{output_extension}}"

    rpath = "-Wl,-soname,$soname"
    if (is_mac) {
      rpath = "-Wl,-install_name,@rpath/$soname"
    }

    command = "$cxx -shared {{ldflags}} {{inputs}} {{solibs}} {{libs}} $rpath -o {{output}}"
    outputs = [
      "{{root_out_dir}}/$soname",
    ]
    output_prefix = "lib"
    default_output_extension = ".so"
    description = "$cxx -shared ... -o {{output}}"
    pool = ":link_pool"
  }

  tool("link") {
    command = "$cxx {{ldflags}} {{inputs}} {{solibs}} {{libs}} -o {{output}}"
    outputs = [
      "{{root_out_dir}}/{{target_output_name}}{{output_extension}}",
    ]
    description = "$cxx ... -o {{output}}"
    pool = ":link_pool"
  }

  tool("stamp") {
    command = "touch {{output}}"
  }

  tool("copy") {
    command = "ln -f {{source}} {{output}} 2>/dev/null || (rm -rf {{output}} && cp -af {{source}} {{output}})"
  }
}