blob: f7f34ea41462828fea3b2cbfac91dab62e55258b [file] [log] [blame]
# Copyright 2014 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.
import("ffmpeg_generated.gni")
import("ffmpeg_options.gni")
import("//build/buildflag_header.gni")
import("//build/config/compiler/compiler.gni")
import("//build/config/sanitizers/sanitizers.gni")
# Path to platform configuration files.
platform_config_root =
"chromium/config/$ffmpeg_branding/$os_config/$ffmpeg_arch"
has_nasm_deps =
ffmpeg_asm_sources != [] &&
(current_cpu == "x86" || current_cpu == "x64") && os_config != "linux-noasm"
if (has_nasm_deps) {
import("//third_party/nasm/nasm_assemble.gni")
# x86inc.asm ignores the PIC flag when compiling for x86 which unfortunately
# causes text relocations in the object files generated by the assembler. We
# must disable the warning to allow linking with lld. Unlike gold, ld which
# will silently allow text relocations, lld support must be explicit.
#
# See https://crbug.com/911658#c19 for more information. Tracked upstream at
# https://trac.ffmpeg.org/ticket/7878
config("fix_textrels") {
ldflags = [ "-Wl,-z,notext" ]
}
nasm_assemble("ffmpeg_nasm") {
sources = ffmpeg_asm_sources
# Ensure the architecture defines go in the command line before the -P
# file below, so don't use defines.
nasm_flags = []
if (current_cpu == "x86") {
nasm_flags += [ "-DARCH_X86_32" ]
} else if (current_cpu == "x64") {
nasm_flags += [ "-DARCH_X86_64" ]
}
inputs = [
# Sets visibility hidden for cglobal functions. Explicitly included
# to avoid overlooking changes to this file in incremental builds.
"libavutil/x86/x86inc.asm",
]
defines = [ "PIC" ]
include_dirs = [
platform_config_root,
"libavcodec/x86",
"libavutil/x86",
".",
]
nasm_flags += [
"-W+error=all",
"-Wno-macro-params-legacy",
"-P" + rebase_path("$platform_config_root/config.asm", root_build_dir),
]
if (is_mac) {
# Necessary to ensure symbols end up with a _ prefix; added by
# yasm_assemble.gni for Windows, but not Mac.
defines += [ "PREFIX" ]
}
# See comments on fix_textrels config.
if (use_lld && current_cpu == "x86" && !is_win) {
all_dependent_configs = [ ":fix_textrels" ]
}
}
}
config("ffmpeg_dependent_config") {
include_dirs = [
platform_config_root,
".",
]
}
if (is_win) {
# Stub generator script and signatures of all functions used by Chrome.
generate_stubs_script = "//tools/generate_stubs/generate_stubs.py"
# Used by ffmpeg_generate_stubs and ffmpeg_generate_def
sig_files = [ "chromium/ffmpeg.sigs" ]
action("ffmpeg_generate_def") {
script = generate_stubs_script
sources = sig_files
outputs = [
"$target_gen_dir/ffmpeg.def",
]
args = [
"-i",
rebase_path(target_out_dir, root_build_dir),
"-o",
rebase_path(target_gen_dir, root_build_dir),
"-t",
"windows_def",
"-m",
"ffmpeg.dll",
] + rebase_path(sources, root_build_dir)
}
}
# gn orders flags on a target before flags from configs. The default config
# adds -Wall, and these flags have to be after -Wall -- so they need to come
# from a config and can't be on the target directly.
config("ffmpeg_warnings") {
if (is_clang) {
cflags = [
"-Wno-absolute-value",
# ffmpeg uses its own deprecated functions.
"-Wno-deprecated-declarations",
# ffmpeg doesn't care about pointer constness.
"-Wno-incompatible-pointer-types",
# ffmpeg doesn't follow usual parentheses conventions.
"-Wno-logical-op-parentheses",
# ffmpeg doesn't care about pointer signedness.
"-Wno-parentheses",
# ffmpeg doesn't care about pointer signedness.
"-Wno-pointer-sign",
# ffmpeg doesn't believe in exhaustive switch statements.
"-Wno-switch",
# matroskadec.c has a "failed:" label that's only used if some
# CONFIG_ flags we don't set are set.
"-Wno-unused-label",
# ffmpeg has a lot of unused variables.
"-Wno-unused-variable",
# This fires on `av_assert0(!"valid element size")` in utils.c
"-Wno-string-conversion",
# This fires on `pos_min` and `pos_max` in
# autorename_libavformat_utils.c
"-Wno-sometimes-uninitialized",
# clock_gettime is marked as 10.12+ in the 10.12 SDK, but ffmpeg does
# correctly check for that before calling.
"-Wno-unguarded-availability",
# ffmpeg contains static functions in header files, which lead
# to unused function warnings. There are a few legit unused
# functions too.
"-Wno-unused-function",
# vp3data.h's vp31_inter_dequant stores '128' in an int8_t array.
"-Wno-constant-conversion",
# utils.c does
# `return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;`
# while -Wstring-plus-int wants &FFMPEG_LICENSE[sizeof(LICENSE_PREFIX)-1]
"-Wno-string-plus-int",
# video_enc_params.c has a condition that is always false when size_t is
# 64 bits.
"-Wno-tautological-constant-out-of-range-compare",
]
if (target_cpu == "arm" || target_cpu == "arm64") {
# ffmpeg uses ARM instructions that clang deems deprecated.
cflags += [ "-Wno-inline-asm" ]
}
if (is_win) {
# This corresponds to /wd4273 below.
cflags += [ "-Wno-inconsistent-dllimport" ]
}
}
}
buildflag_header("ffmpeg_features") {
header = "ffmpeg_features.h"
flags = [ "USE_SYSTEM_FFMPEG=false" ]
}
if (is_component_ffmpeg) {
link_target_type = "source_set"
} else {
# This must be a static_library in non-component builds to avoid pulling
# in many large global arrays (and associated code) into chrome.dll.
link_target_type = "static_library"
}
target(link_target_type, "ffmpeg_internal") {
sources = ffmpeg_c_sources + ffmpeg_gas_sources + [
"$platform_config_root/config.h",
"$platform_config_root/libavutil/avconfig.h",
]
include_dirs = [
platform_config_root,
".",
]
defines = [
"HAVE_AV_CONFIG_H",
"_POSIX_C_SOURCE=200112",
"_XOPEN_SOURCE=600",
"PIC",
"FFMPEG_CONFIGURATION=NULL",
]
if (is_component_ffmpeg) {
configs += [ "//build/config/sanitizers:cfi_icall_disable" ]
}
# Disable internal ffmpeg logs in the official build; this saves ~158kb.
if (is_official_build) {
defines += [ "CHROMIUM_NO_LOGGING" ]
}
# So we can append below and assume they're defined.
cflags = []
ldflags = []
libs = []
deps = [
":ffmpeg_features",
"//third_party/opus",
]
configs -= [ "//build/config/compiler:chromium_code" ]
configs += [
"//build/config/compiler:no_chromium_code",
# These must be after no_chromium_code for warning flags to be ordered
# correctly.
"//build/config/compiler:no_incompatible_pointer_warnings",
":ffmpeg_warnings",
]
# Since we are not often debugging FFmpeg, and performance is
# unacceptable without optimization, freeze the optimizations to -O2.
# If someone really wants -O1 , they can change these in their checkout.
# If you want -O0, see the Gotchas in README.Chromium for why that
# won't work.
#
# In addition to the above reasons, /Od optimization won't remove symbols
# that are under "if (0)" style sections. Which lead to link time errors
# when for example it tries to link an ARM symbol on X86.
configs -= [ "//build/config/compiler:default_optimization" ]
configs += [ "//build/config/compiler:optimize_max" ]
if (ffmpeg_use_atomics_fallback) {
if (is_posix || is_fuchsia) {
include_dirs += [ "compat/atomics/gcc" ]
} else if (is_win) {
include_dirs += [ "compat/atomics/win32" ]
}
}
# On x86, sanitizers will fail to compiler the H264 CABAC code due to
# insufficient registers unless we disable EBP usage. https://crbug.com/786760
#
# Windows builds can't compile without EBP because we can't omit frame
# pointers like we do on posix.
if (current_cpu == "x86") {
if (using_sanitizer || is_win || use_lld) {
defines += [ "HAVE_EBP_AVAILABLE=0" ]
} else {
defines += [ "HAVE_EBP_AVAILABLE=1" ]
}
# Despite the name, this isn't fixing any bugs with the linker. It's just
# preventing ffmpeg from silently emitting text relocations. See discussion
# https://crbug.com/911658#c19 and https://trac.ffmpeg.org/ticket/7878
if (use_lld && !is_win) {
defines += [ "BROKEN_RELOCATIONS=1" ]
}
}
if (is_fuchsia || is_posix) {
cflags += [
"-fPIC",
# ffmpeg uses its own deprecated functions.
"-Wno-deprecated-declarations",
]
if (!(is_android && use_call_graph)) {
# Remove default stack frames config so we can force -fomit-frame-pointer.
configs -= [ "//build/config/compiler:default_stack_frames" ]
cflags += [
"-fomit-frame-pointer",
]
}
if (!is_clang) {
# gcc doesn't have flags for specific warnings, so disable them
# all.
cflags += [ "-w" ]
}
if (current_cpu == "arm" || current_cpu == "arm64") {
asmflags = []
if (arm_float_abi == "hard") {
asmflags += [ "-DHAVE_VFP_ARGS=1" ]
} else {
asmflags += [ "-DHAVE_VFP_ARGS=0" ]
}
}
}
if (is_fuchsia || (is_posix && !is_mac)) {
defines += [
"_ISOC99_SOURCE",
"_LARGEFILE_SOURCE",
]
cflags += [
"-std=c99",
"-pthread",
"-fno-math-errno",
"-fno-signed-zeros",
"-fno-tree-vectorize",
]
ldflags = [
"-L",
rebase_path(target_gen_dir, root_build_dir),
]
if (!is_android && !is_fuchsia) {
# OS=android requires that both -lz and -lm occur after
# -lc++_shared on the link command line. Android link rules
# already include -lm, and we get -lz as a transitive dependency
# of libandroid.so, so simply moving both to the non-Android
# section solves the problem.
#
# The root cause of this problem is certain system libraries
# (libm starting with MNC and libz before MNC, among others)
# re-export the libgcc unwinder, and libc++ exports the
# libc++abi unwinder. As we build against libc++ headers, libc++
# must be the first in the runtime symbol lookup order (among
# all unwinder-providing libraries).
# librt for clock_gettime on precise
libs += [
"m",
"z",
"rt",
]
}
if (is_component_ffmpeg) {
# Export all symbols when building as component.
configs -= [ "//build/config/gcc:symbol_visibility_hidden" ]
configs += [ "//build/config/gcc:symbol_visibility_default" ]
}
}
if (is_mac) {
if (is_component_ffmpeg) {
# Export all symbols when building as component.
configs -= [ "//build/config/gcc:symbol_visibility_hidden" ]
configs += [ "//build/config/gcc:symbol_visibility_default" ]
}
defines += [ "_DARWIN_C_SOURCE" ]
} else if (is_win) {
defines += [
"_ISOC99_SOURCE",
"_LARGEFILE_SOURCE",
"HAVE_AV_CONFIG_H",
]
if (is_component_ffmpeg) {
# Required to avoid 4049 and 4217 errors around redundant imports.
cflags += [
"/FIcompat/msvcrt/snprintf.h",
"/FIcompat/msvcrt/strtod.h",
]
}
# TODO(dalecurtis): We should fix these. http://crbug.com/154421
cflags += [
"/wd4996", # 'function': was declared deprecated
"/wd4018", # 'expression': signed/unsigned mismatch
"/wd4090", # 'operation' : different 'modifier' qualifiers
"/wd4305", # 'identifier': truncation from 'type1' to 'type2'
"/wd4133", # 'type' : incompatible types - from 'type1' to 'type2'
"/wd4146", # unary minus operator applied to unsigned type, result
# still unsigned
"/wd4554", # 'operator' : check operator precedence for possible
# error; use parentheses to clarify precedence
"/wd4028", # formal parameter 'number' different from declaration
"/wd4334", # 'operator' : result of 32-bit shift implicitly
# converted to 64 bits (was 64-bit shift intended?)
"/wd4101", # 'identifier' : unreferenced local variable
"/wd4102", # 'label' : unreferenced label
"/wd4116", # unnamed type definition in parentheses
"/wd4307", # 'operator' : integral constant overflow
"/wd4273", # 'function' : inconsistent DLL linkage
"/wd4005", # 'identifier' : macro redefinition
"/wd4056", # overflow in floating point constant arithmetic
"/wd4756", # overflow in constant arithmetic
]
if (current_cpu == "x64") {
# TODO(wolenetz): We should fix this. http://crbug.com/171009
cflags += [ "/wd4267" ] # Conversion from size_t to 'type'.
}
}
if (has_nasm_deps) {
deps += [ ":ffmpeg_nasm" ]
}
}
if (is_component_ffmpeg) {
shared_library("ffmpeg") {
if (is_android) {
configs -= [ "//build/config/android:hide_all_but_jni_onload" ]
}
public_configs = [ ":ffmpeg_dependent_config" ]
deps = [
":ffmpeg_internal",
]
# So we can append below and assume they're defined.
ldflags = []
if (is_fuchsia || (is_posix && !is_mac)) {
# Fixes warnings PIC relocation when building as component.
ldflags += [
"-Wl,-Bsymbolic",
"-L",
rebase_path(target_gen_dir, root_build_dir),
]
} else if (is_win) {
# Windows component build needs the .def file to export ffmpeg symbols.
deps += [ ":ffmpeg_generate_def" ]
sources = [
"$target_gen_dir/ffmpeg.def",
]
}
if (is_mac && !is_component_build) {
ldflags += [ "-Wl,-install_name,@rpath/libffmpeg.dylib" ]
}
}
} else {
source_set("ffmpeg") {
public_configs = [ ":ffmpeg_dependent_config" ]
deps = [
":ffmpeg_internal",
]
}
}