build/BUILD.gn

# Copyright 2016 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

################################################################################
# DEFAULT BUILD CONFIGURATION
################################################################################

if (is_fuchsia) {
  declare_args() {
    # Path to Fuchsia SDK.
    fuchsia_sdk = "//third_party/fuchsia/sdk"
    fuchsia_clang = "//third_party/fuchsia/clang"

    sysroot = ""
  }

  if (current_cpu == "arm64") {
    sysroot = fuchsia_sdk + "/sysroot/aarch64-fuchsia"
  } else if (current_cpu == "x64") {
    sysroot = fuchsia_sdk + "/sysroot/x86_64-fuchsia"
  }
}

config("debug") {
}

config("release") {
  defines = [ "NDEBUG" ]

  if (is_mac) {
    cflags = [ "-O3" ]
    ldflags = [ "-Wl,-dead_strip" ]
  } else if (is_win) {
    cflags = [
      "/GL",  # LTCG.
      "/O2",
      "/Ob2",  # Both explicit and auto inlining.
      "/Oy-",  # Disable omitting frame pointers, must be after /O2.
      "/Zc:inline",  # Remove unreferenced COMDAT (faster links).
      "/d2Zi+",  # Improve debugging of optimized code.
    ]
    ldflags = [
      "/OPT:ICF",
      "/OPT:REF",
      "/LTCG",
    ]
    arflags = [ "/LTCG" ]
  }
}

config("default") {
  ldflags = []
  if (is_mac || is_fuchsia) {
    cflags = [
      "-Wall",
      "-Wendif-labels",
      "-Werror",
      "-Wextra",
      "-Wno-missing-field-initializers",
      "-Wno-unused-parameter",
      "-Wsign-compare",
      "-fno-rtti",
      "-fno-strict-aliasing",  # See https://crbug.com/32204
      "-fobjc-call-cxx-cdtors",
      "-fstack-protector-all",  # Implies -fstack-protector
      "-fvisibility-inlines-hidden",
      "-fvisibility=hidden",
    ]

    cflags_c = [ "-std=c99" ]
    cflags_cc = [ "-std=c++14" ]
    cflags_objc = cflags_c
    cflags_objcc = cflags_cc

    cflags += [
      "-Wexit-time-destructors",
      "-Wheader-hygiene",
      "-Wnewline-eof",
      "-Wstring-conversion",
    ]
  } else if (is_win) {
    cflags = [
      "/DNOMINMAX",
      "/DUNICODE",
      "/DWIN32_LEAN_AND_MEAN",
      "/D_CRT_SECURE_NO_WARNINGS",
      "/D_HAS_EXCEPTIONS=0",
      "/D_UNICODE",
      "/W4",
      "/WX",
      "/wd4100",  # Unreferenced formal parameter.
      "/wd4127",  # Conditional expression is constant.
      "/wd4351",  # New behavior: elements of array will be default initialized.
      "/wd4530",  # Exceptions disabled.
      "/wd4702",  # Unreachable code.
      "/wd4996",  # 'X' was declared deprecated.
    ]
  }

  if (is_fuchsia) {
    if (target_cpu == "arm64") {
      cflags += [ "--target=aarch64-fuchsia" ]
      ldflags += [ "--target=aarch64-fuchsia" ]
    } else if (target_cpu == "x64") {
      cflags += [ "--target=x86_64-fuchsia" ]
      ldflags += [ "--target=x86_64-fuchsia" ]
    } else {
      assert(false, "Unsupported architecture")
    }

    libs = [
      "fdio",
      "zircon",
    ]

    # Pass the sysroot to all C compiler variants, the assembler, and linker.
    sysroot_flags = [ "--sysroot=" + rebase_path(sysroot, root_build_dir) ]
    ldflags += sysroot_flags
    cflags_c += sysroot_flags
    cflags_cc += sysroot_flags
    cflags_objc += sysroot_flags
    cflags_objcc += sysroot_flags
  }

  if (is_debug) {
    configs = [ ":debug" ]
  } else {
    configs = [ ":release" ]
  }
}

################################################################################
# TOOLCHAIN DEFINITIONS
################################################################################

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

  if (is_fuchsia) {
    cc = rebase_path(fuchsia_clang, root_build_dir) + "/bin/clang"
    cxx = rebase_path(fuchsia_clang, root_build_dir) + "/bin/clang++"
    ld = cxx
  } else {
    cc = "clang"
    cxx = "clang++"
    ld = cxx
  }

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

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

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

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

  tool("alink") {
    if (is_mac) {
      command = "libtool -static {{arflags}} -o {{output}} {{inputs}}"
    } else {
      command = "ar rcsD {{arflags}} -o {{output}} {{inputs}}"
    }
    description = "LIBTOOL-STATIC {{output}}"
    default_output_dir = "{{target_out_dir}}"
    default_output_extension = ".a"
    output_prefix = "lib"
    outputs = [
      "{{output_dir}}/{{target_output_name}}{{output_extension}}",
    ]
  }

  tool("solink_module") {
    # TODO(scottmg): This will need to do -framework, etc. for macOS.
    soname = "{{target_output_name}}{{output_extension}}"  # e.g. "libfoo.so".
    sofile = "{{output_dir}}/$soname"
    rspfile = sofile + ".rsp"

    command = "$ld -shared {{ldflags}} -o \"$sofile\" -Wl,-soname=\"$soname\" @\"$rspfile\""
    rspfile_content = "-Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive {{libs}}"
    description = "SOLINK_MODULE $sofile"

    default_output_extension = ".so"
    default_output_dir = "{{root_out_dir}}"
    output_prefix = "lib"
    outputs = [
      sofile,
    ]
  }

  tool("link") {
    exename = "{{target_output_name}}{{output_extension}}"
    outfile = "{{output_dir}}/$exename"
    rspfile = "$outfile.rsp"

    default_output_extension = ""

    default_output_dir = "{{root_out_dir}}"

    start_group_flag = "-Wl,--start-group"
    end_group_flag = "-Wl,--end-group "
    command = "$ld {{ldflags}} -o \"$outfile\" $start_group_flag @\"$rspfile\" {{solibs}} $end_group_flag {{libs}}"

    description = "LINK $outfile"
    rspfile_content = "{{inputs}}"
    outputs = [
      outfile,
    ]
  }

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

toolchain("msvc_toolchain") {
  # We don't support all the cross blah-de-blah that Chromium does here. The
  # environment must be pre-setup by a vcvarsall.bat invocation. @rsp files are
  # also not used, for simplicity, and because mini_chromium/Crashpad shouldn't
  # require them in any configurations.
  cc = "cl.exe"
  cxx = "cl.exe"
  ar = "lib.exe"
  ld = "link.exe"
  helper_path = rebase_path("win_helper.py")

  tool("cc") {
    depfile = "{{output}}.d"
    command = "$cc /nologo /showIncludes {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} /c {{source}} /Fo{{output}}"
    depsformat = "msvc"
    description = "CC {{output}}"
    outputs = [
      "{{source_out_dir}}/{{target_output_name}}.{{source_name_part}}.obj",
    ]
  }
  tool("cxx") {
    depfile = "{{output}}.d"
    command = "$cxx /nologo /showIncludes {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}} /c {{source}} /Fo{{output}}"
    depsformat = "msvc"
    description = "CXX {{output}}"
    outputs = [
      "{{source_out_dir}}/{{target_output_name}}.{{source_name_part}}.obj",
    ]
  }
  tool("alink") {
    command = "$python_path $helper_path link-wrapper $ar /nologo /out:{{output}} {{arflags}} {{inputs}}"
    description = "LIB {{output}}"
    outputs = [
      "{{target_out_dir}}/{{target_output_name}}{{output_extension}}",
    ]
    default_output_extension = ".lib"
    output_prefix = ""
  }
  tool("link") {
    outputs = [
      "{{root_out_dir}}/{{target_output_name}}{{output_extension}}",
    ]
    command = "$python_path $helper_path link-wrapper $ld /nologo /OUT:{{output}} {{ldflags}} {{inputs}} {{solibs}} {{libs}}"
    description = "LINK {{output}}"
    default_output_extension = ".exe"
  }
  tool("stamp") {
    command = "$python_path $helper_path stamp {{output}}"
    description = "STAMP {{output}}"
  }
}