gn/standalone/BUILD.gn

# Copyright (C) 2017 The Android Open Source Project
#
# 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.

import("//gn/standalone/android.gni")
import("//gn/standalone/sanitizers/sanitizers.gni")

config("extra_warnings") {
  cflags = [
    "-Wextra",
    "-Wno-unused-parameter",
  ]
  if (is_clang) {
    cflags += [
      "-Weverything",
      "-Wno-c++98-compat-pedantic",
      "-Wno-c++98-compat",
      "-Wno-gnu-include-next",
      "-Wno-gnu-statement-expression",
      "-Wno-gnu-zero-variadic-macro-arguments",
      "-Wno-padded",
      "-Wno-reserved-id-macro",
      "-Wno-weak-vtables",
    ]
  }
}

config("no_exceptions") {
  cflags = [ "-fno-exceptions" ]
}

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

config("visibility_hidden") {
  cflags = [ "-fvisibility=hidden" ]
}

config("default") {
  asmflags = []
  cflags = []
  cflags_c = []
  cflags_cc = []
  defines = []
  ldflags = []
  libs = []

  cflags_cc += [ "-std=c++11" ]

  cflags += [
    "-fstrict-aliasing",
    "-fstack-protector",
    "-fPIC",
    "-Wa,--noexecstack",
    "-Wformat",
    "-Wall",
    "-Werror",
  ]

  # Color compiler output, see https://github.com/ninja-build/ninja/wiki/FAQ
  if (is_clang) {
    cflags += [
      "-fcolor-diagnostics",
      "-Wno-unknown-warning-option",
    ]
  } else {
    cflags += [ "-Wno-unknown-warning" ]
  }

  if (current_cpu == "arm") {
    cflags += [
      "-march=armv7-a",
      "-mfpu=neon",
      "-mthumb",
    ]
  } else if (current_cpu == "x86") {
    asmflags += [ "-m32" ]
    cflags += [
      "-m32",
      "-msse2",
      "-mfpmath=sse",
    ]
    ldflags += [ "-m32" ]
  } else if (current_cpu == "arm64") {
    cflags += [ "-fno-omit-frame-pointer" ]
  }

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

  if (is_android) {
    libs += [ "log" ]
  }

  if (is_android) {
    asmflags += [ "--target=$android_abi_target" ]
    cflags += [
      "--sysroot=$android_compile_sysroot",
      "-isystem$android_compile_sysroot/$android_compile_sysroot_subdir",
      "-isystem$android_compile_sysroot",
      "-DANDROID",
      "-D__ANDROID_API__=21",
      "--target=$android_abi_target",
    ]
    cflags_cc += [
      "-I$android_ndk_root/sources/cxx-stl/llvm-libc++/include",
      "-I$android_ndk_root/sources/android/support/include",
      "-I$android_ndk_root/sources/cxx-stl/llvm-libc++abi/include",
    ]
    ldflags += [
      "-Wl,-z,nocopyreloc",
      "-gcc-toolchain",
      "$android_toolchain_root",
      "--sysroot=$android_ndk_root/$android_link_sysroot_subdir",
      "--target=$android_abi_target",
      "-Wl,--exclude-libs,libunwind.a",
      "-Wl,--exclude-libs,libgcc.a",
      "-Wl,--exclude-libs,libc++_static.a",
      "-Wl,--build-id",
      "-Wl,--no-undefined",
      "-Wl,-z,noexecstack",
      "-Wl,-z,relro",
      "-Wl,-z,now",
      "-Wl,--warn-shared-textrel",
      "-Wl,--fatal-warnings",
    ]
    lib_dirs = [ "$android_ndk_root/sources/cxx-stl/llvm-libc++/libs/$android_app_abi" ]
    libs += [
      "gcc",
      "c++_static",
      "c++abi",
      "android_support",
    ]
  }
}

config("debug_symbols") {
  cflags = [
    "-g",
    "-O0",
  ]
  if (is_android || is_linux) {
    cflags += [ "-funwind-tables" ]
    ldflags = [ "-rdynamic" ]
  }
}

config("release") {
  cflags = [
    "-fdata-sections",
    "-ffunction-sections",
  ]
  if (is_android) {
    cflags += [ "-Oz" ]
  } else {
    cflags += [ "-O3" ]
  }
  if (is_mac) {
    ldflags = [ "-dead_strip" ]
  } else {
    ldflags = [
      "-fuse-ld=gold",
      "-Wl,--gc-sections",
      "-Wl,--icf=all",
      "-Wl,-O1",
    ]
  }
  defines = [ "NDEBUG" ]
}

config("shared_library") {
  if (is_android || is_linux) {
    ldflags = [ "-fPIC" ]
  }
}

config("executable") {
  ldflags = []

  # Android will refuse to run executables if they aren't position independent.
  # Instead on Linux there isn't any need and they break ASan (goo.gl/paFR6K).
  if (is_android) {
    asmflags = [ "-fPIE" ]
    cflags = [ "-fPIE" ]
    ldflags += [ "-pie" ]
  }

  # -rpath stores the path to the linked shared libraries into the binary, so
  # that they can be launched without passing any LD_LIBRARY_PATH. It's
  # supported only by Linux, not Android. But concretely we need this only when
  # use_custom_libcxx=true && custom_libcxx_is_static=false, which happens only
  # on Linux right now.
  if (is_linux) {
    ldflags += [
      "-Wl,-rpath=\$ORIGIN/.",
      "-Wl,-rpath-link=.",
    ]
  }
}