blob: 3e06c162cf57fe959b3cce69181cdc8f56ae9c77 [file] [log] [blame]
# Copyright (c) 2013 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.
declare_args() {
# The optimization level to use for debug builds.
if (is_android) {
# On Android we kind of optimize some things that don't affect debugging
# much even when optimization is disabled to get the binary size down.
debug_optimization_level = "s"
} else {
debug_optimization_level = "2"
}
}
import("//build/config/android/config.gni")
if (current_cpu == "arm") {
import("//build/config/arm.gni")
}
if (is_win) {
import("//build/config/win/visual_studio_version.gni")
}
import("//build/toolchain/ccache.gni")
# default_include_dirs ---------------------------------------------------------
#
# This is a separate config so that third_party code (which would not use the
# source root and might have conflicting versions of some headers) can remove
# this and specify their own include paths.
config("default_include_dirs") {
include_dirs = [
"//",
root_gen_dir,
]
}
if (!is_win) {
using_sanitizer = is_asan || is_lsan || is_msan || is_tsan || is_ubsan
}
# compiler ---------------------------------------------------------------------
#
# Base compiler configuration.
#
# See also "runtime_library" below for related stuff and a discussion about
# where stuff should go. Put warning related stuff in the "warnings" config.
config("compiler") {
asmflags = []
cflags = []
cflags_c = []
cflags_cc = []
cflags_objcc = []
ldflags = []
defines = []
# In general, Windows is totally different, but all the other builds share
# some common GCC configuration. This section sets up Windows and the common
# GCC flags, and then we handle the other non-Windows platforms specifically
# below.
if (is_win) {
# Windows compiler flags setup.
# -----------------------------
cflags += [
"/Gy", # Enable function-level linking.
"/GS", # Enable buffer security checking.
"/FS", # Preserve previous PDB behavior.
]
} else {
# Common GCC compiler flags setup.
# --------------------------------
common_flags = [
# Not exporting C++ inline functions can generally be applied anywhere
# so we do so here. Normal function visibility is controlled by
# //build/config/gcc:symbol_visibility_hidden.
"-fvisibility-inlines-hidden",
]
if (!is_product) {
common_flags += [
# We need the frame pointer for CPU and heap profiling.
"-fno-omit-frame-pointer",
]
}
cflags_cc += common_flags
cflags_objcc += common_flags
# Linker warnings.
if (current_cpu != "arm" && !is_mac) {
# TODO(jochen): Enable this on ChromeOS on arm. http://crbug.com/356580
ldflags += [ "-Wl,--fatal-warnings" ]
}
# Enable mitigations for Cortex-A53 Erratum #843419 bug.
if (current_cpu == "arm64" && is_clang) {
ldflags += [ "-Wl,--fix-cortex-a53-843419" ]
}
# Common options for AddressSanitizer, LeakSanitizer, ThreadSanitizer and
# MemorySanitizer
if (using_sanitizer) {
cflags += [ "-gline-tables-only" ]
}
if (is_asan) {
cflags += [ "-fsanitize=address" ]
ldflags += [ "-fsanitize=address" ]
}
if (is_lsan) {
cflags += [ "-fsanitize=leak" ]
ldflags += [ "-fsanitize=leak" ]
}
if (is_msan) {
cflags += [ "-fsanitize=memory" ]
ldflags += [ "-fsanitize=memory" ]
}
if (is_tsan) {
cflags += [ "-fsanitize=thread" ]
ldflags += [ "-fsanitize=thread" ]
}
if (is_ubsan) {
cflags += [ "-fsanitize=undefined" ]
ldflags += [ "-fsanitize=undefined" ]
}
}
if (is_clang && is_debug) {
# Allow comparing the address of references and 'this' against 0
# in debug builds. Technically, these can never be null in
# well-defined C/C++ and Clang can optimize such checks away in
# release builds, but they may be used in asserts in debug builds.
extra_flags = [
"-Wno-undefined-bool-conversion",
"-Wno-tautological-undefined-compare",
]
cflags_cc += extra_flags
cflags_objcc += extra_flags
}
# Mac-specific compiler flags setup.
# ----------------------------------
if (is_mac) {
# These flags are shared between the C compiler and linker.
common_mac_flags = [ "-fno-exceptions" ]
# CPU architecture.
if (current_cpu == "x64") {
common_mac_flags += [
"-arch",
"x86_64",
]
} else if (current_cpu == "x86") {
common_mac_flags += [
"-arch",
"i386",
]
} else if (current_cpu == "arm") {
common_mac_flags += [
"-arch",
"armv7",
]
} else if (current_cpu == "arm64") {
common_mac_flags += [
"-arch",
"arm64",
]
}
cflags += common_mac_flags
# Without this, the constructors and destructors of a C++ object inside
# an Objective C struct won't be called, which is very bad.
cflags_objcc += [ "-fobjc-call-cxx-cdtors" ]
cflags_c += [ "-std=c99" ]
ldflags += common_mac_flags
} else if (is_posix) {
# CPU architecture. We may or may not be doing a cross compile now, so for
# simplicitly we always explicitly set the architecture.
if (current_cpu == "x64") {
cflags += [
"-m64",
"-march=x86-64",
"-msse2",
]
ldflags += [ "-m64" ]
} else if (current_cpu == "x86") {
cflags += [
"-m32",
"-msse2",
"-mfpmath=sse",
]
ldflags += [ "-m32" ]
if (is_clang) {
cflags += [
# Else building libyuv gives clang's register allocator issues,
# see llvm.org/PR15798 / crbug.com/233709
"-mno-omit-leaf-frame-pointer",
]
}
} else if (current_cpu == "arm") {
cflags += [
"-march=$arm_arch",
"-mfloat-abi=$arm_float_abi",
]
if (arm_tune != "") {
cflags += [ "-mtune=$arm_tune" ]
}
if (!is_clang) {
# Clang doesn't support these flags.
cflags += [
# The tree-sra optimization (scalar replacement for
# aggregates enabling subsequent optimizations) leads to
# invalid code generation when using the Android NDK's
# compiler (r5-r7). This can be verified using
# webkit_unit_tests' WTF.Checked_int8_t test.
"-fno-tree-sra",
# The following option is disabled to improve binary
# size and performance in gcc 4.9.
"-fno-caller-saves",
]
}
}
cflags += [ "-fno-exceptions" ]
}
# Linux/Android common flags setup.
# ---------------------------------
if (is_linux || is_android) {
ldflags += [
"-Wl,-z,noexecstack",
"-Wl,-z,now",
"-Wl,-z,relro",
"-Wl,--build-id=none",
]
}
# We need -fPIC:
# 1. On ARM for tcmalloc.
# 2. On Android.
# 3. When using the sanitizers.
# Otherwise there is a performance hit, in particular on ia32.
if (is_android || is_asan || is_lsan || is_msan || is_tsan || is_ubsan ||
(is_linux && current_cpu != "x86") || is_fuchsia) {
cflags += [ "-fPIC" ]
ldflags += [ "-fPIC" ]
}
# Linux-specific compiler flags setup.
# ------------------------------------
if (is_linux) {
if (is_clang) {
if (current_cpu == "arm") {
cflags += [ "--target=armv7-linux-gnueabihf" ]
ldflags += [ "--target=armv7-linux-gnueabihf" ]
} else if (current_cpu == "arm64") {
cflags += [ "--target=aarch64-linux-gnu" ]
ldflags += [ "--target=aarch64-linux-gnu" ]
} else if (current_cpu == "x86") {
cflags += [ "--target=i386-linux-gnu" ]
ldflags += [ "--target=i386-linux-gnu" ]
}
}
}
# Clang-specific compiler flags setup.
# ------------------------------------
if (is_clang) {
cflags += [ "-fcolor-diagnostics" ]
}
# C++11 compiler flags setup.
# ---------------------------
if (is_win) {
# Up-to-date toolchain MSVC doesn't support c++11 flag any longer.
cc_std = [ "/std:c++14" ]
} else if (is_fuchsia) {
cc_std = [ "-std=c++17" ]
} else {
cc_std = [ "-std=c++11" ]
}
cflags_cc += cc_std
cflags_objcc += cc_std
# Android-specific flags setup.
# -----------------------------
if (is_android) {
cflags += [
"-ffunction-sections",
"-funwind-tables",
"-fno-short-enums",
"-nostdinc++",
]
if (!is_clang) {
# Clang doesn't support these flags.
cflags += [ "-finline-limit=64" ]
}
if (is_asan) {
# Android build relies on -Wl,--gc-sections removing unreachable code.
# ASan instrumentation for globals inhibits this and results in a library
# with unresolvable relocations.
# TODO(eugenis): find a way to reenable this.
cflags += [ "-mllvm -asan-globals=0" ]
}
defines += [ "ANDROID" ]
# The NDK has these things, but doesn't define the constants
# to say that it does. Define them here instead.
defines += [ "HAVE_SYS_UIO_H" ]
# Use gold for Android for most CPU architectures.
if (current_cpu == "x86" || current_cpu == "x64" || current_cpu == "arm" ||
current_cpu == "arm64") {
ldflags += [ "-fuse-ld=gold" ]
if (is_clang) {
# Let clang find the ld.gold in the NDK.
toolchain_root = rebase_path(android_toolchain_root, root_build_dir)
ldflags += [ "--gcc-toolchain=$toolchain_root" ]
ldflags += [ "-B${toolchain_root}/bin" ]
}
}
ldflags += [
# Don't allow visible symbols from libgcc or libc++ to be
# re-exported.
"-Wl,--exclude-libs=libgcc.a",
"-Wl,--exclude-libs=libc++_static.a",
]
if (is_clang) {
if (current_cpu == "arm") {
cflags += [ "--target=arm-linux-androideabi" ]
ldflags += [ "--target=arm-linux-androideabi" ]
} else if (current_cpu == "arm64") {
cflags += [ "--target=aarch64-linux-android" ]
ldflags += [ "--target=aarch64-linux-android" ]
} else if (current_cpu == "x86") {
cflags += [ "--target=i686-linux-androideabi" ]
ldflags += [ "--target=i686-linux-androideabi" ]
} else if (current_cpu == "x64") {
cflags += [ "--target=x86_64-linux-androideabi" ]
ldflags += [ "--target=x86_64-linux-androideabi" ]
}
}
}
# We want to force a recompile and relink of the world whenever our toolchain
# changes since artifacts from an older version of the toolchain may or may
# not be compatible with newer ones. To achieve this, we insert a synthetic
# define into the compile line.
if (is_clang && (is_linux || is_mac)) {
if (is_linux) {
toolchain_stamp_file =
"//buildtools/linux-x64/clang/.versions/clang.cipd_version"
} else {
toolchain_stamp_file =
"//buildtools/mac-x64/clang/.versions/clang.cipd_version"
}
cipd_version = read_file(toolchain_stamp_file, "json")
defines = [ "TOOLCHAIN_VERSION=${cipd_version.instance_id}" ]
}
# Assign any flags set for the C compiler to asmflags so that they are sent
# to the assembler. The Windows assembler takes different types of flags
# so only do so for posix platforms.
if (is_posix) {
asmflags += cflags
asmflags += cflags_c
}
}
# This is separate from :compiler_codegen (and not even a sub-config there)
# so that some targets can remove it from the list with:
# configs -= [ "//build/config/compiler:clang_stackrealign" ]
# See https://crbug.com/556393 for details of where it must be avoided.
config("clang_stackrealign") {
if (is_clang && current_cpu == "x86" && !is_nacl && !is_win) {
cflags = [
# Align the stack on 16-byte boundaries, http://crbug.com/418554.
"-mstack-alignment=16",
"-mstackrealign",
]
}
}
config("compiler_arm_fpu") {
if (current_cpu == "arm") {
cflags = [ "-mfpu=$arm_fpu" ]
}
}
config("compiler_arm_thumb") {
if (current_cpu == "arm") {
if (arm_use_thumb) {
cflags = [ "-mthumb" ]
if (is_android && !is_clang) { # Clang doesn't support this option.
cflags += [ "-mthumb-interwork" ]
}
asmflags = cflags
}
}
}
# runtime_library -------------------------------------------------------------
#
# Sets the runtime library and associated options.
#
# How do you determine what should go in here vs. "compiler" above? Consider if
# a target might choose to use a different runtime library (ignore for a moment
# if this is possible or reasonable on your system). If such a target would
# want to change or remove your option, put it in the runtime_library config.
# If a target wants the option regardless, put it in the compiler config.
config("runtime_library") {
cflags = []
defines = []
ldflags = []
lib_dirs = []
libs = []
# Static CRT.
if (is_win) {
if (is_debug) {
cflags += [ "/MTd" ]
} else {
cflags += [ "/MT" ]
}
defines += [
"__STD_C",
"_CRT_RAND_S",
"_CRT_SECURE_NO_DEPRECATE",
"_HAS_EXCEPTIONS=0",
"_SCL_SECURE_NO_DEPRECATE",
]
}
if (is_linux) {
libs += [ "dl" ]
} else if (is_android) {
# Android standard library setup.
if (is_clang) {
# Work around incompatibilities between bionic and clang headers.
defines += [ "__compiler_offsetof=__builtin_offsetof" ]
}
defines += [ "__GNU_SOURCE=1" ] # Necessary for clone().
ldflags += [
"-Wl,--warn-shared-textrel",
"-nostdlib",
]
# NOTE: The libc++ header include paths below are specified in cflags
# rather than include_dirs because they need to come after include_dirs.
# Think of them like system headers, but don't use '-isystem' because the
# arm-linux-androideabi-4.4.3 toolchain (circa Gingerbread) will exhibit
# strange errors. The include ordering here is important; change with
# caution.
cflags += [
"-isystem" + rebase_path("$android_libcpp_root/include", root_build_dir),
"-isystem" + rebase_path(
"$android_ndk_root/sources/cxx-stl/llvm-libc++abi/include",
root_build_dir),
"-isystem" +
rebase_path("$android_ndk_root/sources/android/support/include",
root_build_dir),
"-isystem" + rebase_path(
"$android_ndk_root/sysroot/usr/include/$android_target_triple",
root_build_dir),
"-D__ANDROID_API__=$android_api_level",
]
lib_dirs += [ "$android_libcpp_root/libs/$android_app_abi" ]
libs += [
"$android_libcpp_library",
"c++abi",
]
if (android_api_level < 21) {
libs += [ "android_support" ]
}
if (current_cpu == "arm") {
libs += [ "unwind" ]
}
libs += [
"gcc",
"c",
"dl",
"m",
]
# Clang with libc++ does not require an explicit atomic library reference.
if (!is_clang) {
libs += [ "atomic" ]
}
}
}
# default_warning_flags collects all warning flags that are used by default.
# This is in a variable instead of a config so that it can be used in
# both chromium_code and no_chromium_code. This way these flags are guaranteed
# to appear on the compile command line after -Wall.
default_warning_flags = []
default_warning_flags_cc = []
if (is_win) {
if (current_cpu != "x86") {
default_warning_flags += [ "/WX" ] # Treat warnings as errors.
}
if (is_clang) {
default_warning_flags += [
"-Wno-deprecated-declarations", # crashpad
"-Wno-ignored-pragma-optimize", # icu, double-conversion
"-Wno-implicit-int-float-conversion", # icu
"-Wno-macro-redefined",
"-Wno-microsoft-cast",
"-Wno-microsoft-unqualified-friend",
"-Wno-unknown-argument", # icu
"-Wno-unused-value", # crashpad
]
} else {
default_warning_flags += [
# Permanent.
"/wd4091", # typedef warning from dbghelp.h
"/wd4722", # destructor never returns
# Investigate.
"/wd4312", # int to pointer of greater size conversion.
"/wd4838", # Narrowing conversion required.
"/wd4172", # Returning address of local.
"/wd4005", # Redefinition of macros for PRId64 etc.
"/wd4311", # Pointer truncation from PVOID to DWORD.
"/wd4477", # Format string requires wchar_t*
]
}
} else {
# Common GCC warning setup.
default_warning_flags += [
# Enables.
"-Wendif-labels", # Weird old-style text after an #endif.
# Disables.
"-Wno-missing-field-initializers", # "struct foo f = {0};"
"-Wno-unused-parameter", # Unused function parameters.
]
if (is_clang) {
default_warning_flags += [ "-Wno-tautological-constant-compare" ]
} else {
default_warning_flags +=
[ "-Wno-ignored-qualifiers" ] # Warnings in BoringSSL headers
}
if (is_mac) {
# TODO(abarth): Re-enable once https://github.com/domokit/mojo/issues/728
# is fixed.
# default_warning_flags += [ "-Wnewline-eof" ]
# When compiling Objective-C, warns if a method is used whose
# availability is newer than the deployment target. This is not
# required when compiling Chrome for iOS.
default_warning_flags += [ "-Wpartial-availability" ]
}
# Suppress warnings about ABI changes on ARM (Clang doesn't give this
# warning).
if (current_cpu == "arm" && !is_clang) {
default_warning_flags += [ "-Wno-psabi" ]
}
# The Raspberry Pi 1 toolchain enables this warning, but Dart doesn't build
# cleanly with it.
if (is_linux && !is_clang && current_cpu == "arm" && arm_version == 6) {
default_warning_flags += [ "-Wno-type-limits" ]
}
if (is_android) {
# Disable any additional warnings enabled by the Android build system but
# which chromium does not build cleanly with (when treating warning as
# errors).
default_warning_flags += [
"-Wno-extra",
"-Wno-ignored-qualifiers",
"-Wno-type-limits",
]
default_warning_flags_cc += [
# Other things unrelated to -Wextra:
"-Wno-non-virtual-dtor",
"-Wno-sign-promo",
]
}
}
# chromium_code ---------------------------------------------------------------
#
# Toggles between higher and lower warnings for code that is (or isn't)
# part of Chromium.
config("chromium_code") {
if (is_win) {
# TODO(zra): Enable higher warning levels.
# cflags = [ "/W4" ] # Warning level 4.
cflags = []
} else {
cflags = [
"-Wall",
"-Wextra",
"-Werror",
]
defines = []
if (!using_sanitizer && !is_clang) {
# _FORTIFY_SOURCE isn't really supported by Clang now, see
# http://llvm.org/bugs/show_bug.cgi?id=16821.
# It seems to work fine with Ubuntu 12 headers though, so use it in
# official builds.
#
# Non-chromium code is not guaranteed to compile cleanly with
# _FORTIFY_SOURCE. Also, fortified build may fail when optimizations are
# disabled, so only do that for Release build.
defines += [ "_FORTIFY_SOURCE=2" ]
}
}
cflags += default_warning_flags
cflags_cc = default_warning_flags_cc
}
config("no_chromium_code") {
cflags = []
cflags_cc = []
defines = []
if (is_win) {
defines += [
"_CRT_NONSTDC_NO_WARNINGS",
"_CRT_NONSTDC_NO_DEPRECATE",
]
}
cflags += default_warning_flags
cflags_cc += default_warning_flags_cc
}
# rtti ------------------------------------------------------------------------
#
# Allows turning Run-Time Type Identification on or off.
config("rtti") {
if (is_win) {
cflags_cc = [ "/GR" ]
}
}
config("no_rtti") {
if (is_win) {
cflags_cc = [ "/GR-" ]
} else {
rtti_flags = [ "-fno-rtti" ]
cflags_cc = rtti_flags
cflags_objcc = rtti_flags
}
}
# Optimization -----------------------------------------------------------------
#
# Note that BUILDCONFIG.gn sets up a variable "default_optimization_config"
# which it will assign to the config it implicitly applies to every target. If
# you want to override the optimization level for your target, remove this
# config (which will expand differently for debug or release builds), and then
# add back the one you want to override it with:
#
# configs -= default_optimization_config
# configs += [ ":optimize_max" ]
# Shared settings.
# IMPORTANT: On Windows "/O1" and "/O2" must go before the common flags.
if (is_win) {
common_optimize_on_cflags = [
"/Ob2", # Both explicit and auto inlining.
"/Oy-", # Disable omitting frame pointers, must be after /O2.
]
if (!is_asan) {
common_optimize_on_cflags += [
# Put data in separate COMDATs. This allows the linker
# to put bit-identical constants at the same address even if
# they're unrelated constants, which saves binary size.
# This optimization can't be used when ASan is enabled because
# it is not compatible with the ASan ODR checker.
"/Gw",
]
}
common_optimize_on_ldflags = [
"/OPT:REF",
"/OPT:ICF",
]
} else {
common_optimize_on_cflags = [
# Don't emit the GCC version ident directives, they just end up in the
# .comment section taking up binary size.
"-fno-ident",
# Put data and code in their own sections, so that unused symbols
# can be removed at link time with --gc-sections.
"-fdata-sections",
"-ffunction-sections",
]
common_optimize_on_ldflags = []
if (is_android) {
common_optimize_on_ldflags += [
# Warn in case of text relocations.
"-Wl,--warn-shared-textrel",
]
}
if (is_mac) {
# Mac dead code stripping requires symbols.
common_optimize_on_ldflags += [ "-Wl,-dead_strip" ]
} else {
# Non-Mac Posix linker flags.
common_optimize_on_ldflags += [
# Specifically tell the linker to perform optimizations.
# See http://lwn.net/Articles/192624/ .
"-Wl,-O1",
"-Wl,--gc-sections",
]
if (is_clang && !using_sanitizer) {
# Identical code folding to reduce size.
# Warning: This changes C/C++ semantics of function pointer comparison.
common_optimize_on_ldflags += [ "-Wl,--icf=all" ]
}
if (!using_sanitizer) {
# Functions interposed by the sanitizers can make ld think
# that some libraries aren't needed when they actually are,
# http://crbug.com/234010. As workaround, disable --as-needed.
common_optimize_on_ldflags += [ "-Wl,--as-needed" ]
}
}
}
# Default "optimization on" config. On Windows, this favors size over speed.
config("optimize") {
if (is_win) {
# Favor size over speed, /O1 must be before the common flags. The GYP
# build also specifies /Os and /GF but these are implied by /O1.
cflags = [ "/O2" ] + common_optimize_on_cflags + [ "/Oi" ]
} else if (is_android) {
cflags = [ "-Os" ] + common_optimize_on_cflags # Favor size over speed.
} else {
cflags = [ "-O3" ] + common_optimize_on_cflags
}
ldflags = common_optimize_on_ldflags
}
# Turn off optimizations.
config("no_optimize") {
if (is_win) {
# The only difference on windows is that the inlining is less aggressive.
# (We accept the default level). Otherwise it is very slow.
cflags = [
"/O${debug_optimization_level}", # Do some optimizations.
"/Oy-", # Disable omitting frame pointers, must be after /O2.
]
} else if (is_android) {
# On Android we kind of optimize some things that don't affect debugging
# much even when optimization is disabled to get the binary size down.
cflags = [
"-O${debug_optimization_level}",
"-fdata-sections",
"-ffunction-sections",
]
ldflags = common_optimize_on_ldflags
} else {
cflags = [
"-O${debug_optimization_level}",
"-fdata-sections",
"-ffunction-sections",
]
}
}
# These are two named configs that zlib's BUILD.gn expects to exist.
config("default_optimization") {
}
config("optimize_speed") {
}
# Symbols ----------------------------------------------------------------------
config("symbols") {
if (is_win) {
import("//build/toolchain/goma.gni")
if (use_goma) {
cflags = [ "/Z7" ] # No PDB file
} else {
cflags = [ "/Zi" ] # Produce PDB file, no edit and continue.
}
ldflags = [ "/DEBUG" ]
} else {
cflags = [
"-g3",
"-ggdb3",
]
}
}