|  | # 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. | 
|  |  | 
|  | import("//build/config/android/config.gni") | 
|  | import("//build/config/clang/clang.gni") | 
|  | import("//build/config/sanitizers/sanitizers.gni") | 
|  | import("//build/config/v8_target_cpu.gni") | 
|  | import("//build/toolchain/cc_wrapper.gni") | 
|  | import("//build/toolchain/clang_static_analyzer.gni") | 
|  | import("//build/toolchain/goma.gni") | 
|  | import("//build/toolchain/toolchain.gni") | 
|  |  | 
|  | if (is_nacl) { | 
|  | # To keep NaCl variables out of builds that don't include NaCl, all | 
|  | # variables defined in nacl/config.gni referenced here should be protected by | 
|  | # is_nacl conditions. | 
|  | import("//build/config/nacl/config.gni") | 
|  | } | 
|  |  | 
|  | # Path to the Clang static analysis wrapper script. | 
|  | # REVIEWERS: can you suggest a better location for this? | 
|  | # GN is really picky about dead stores of variables except at the global scope. | 
|  | analyzer_wrapper = | 
|  | rebase_path("//build/toolchain/clang_static_analyzer_wrapper.py", | 
|  | root_build_dir) + " --mode=clang" | 
|  |  | 
|  | # This template defines a toolchain for something that works like gcc | 
|  | # (including clang). | 
|  | # | 
|  | # It requires the following variables specifying the executables to run: | 
|  | #  - ar | 
|  | #  - cc | 
|  | #  - cxx | 
|  | #  - ld | 
|  | # | 
|  | # Optional parameters that control the tools: | 
|  | # | 
|  | #  - extra_cflags | 
|  | #      Extra flags to be appended when compiling C files (but not C++ files). | 
|  | #  - extra_cppflags | 
|  | #      Extra flags to be appended when compiling both C and C++ files. "CPP" | 
|  | #      stands for "C PreProcessor" in this context, although it can be | 
|  | #      used for non-preprocessor flags as well. Not to be confused with | 
|  | #      "CXX" (which follows). | 
|  | #  - extra_cxxflags | 
|  | #      Extra flags to be appended when compiling C++ files (but not C files). | 
|  | #  - extra_asmflags | 
|  | #      Extra flags to be appended when compiling assembly. | 
|  | #  - extra_ldflags | 
|  | #      Extra flags to be appended when linking | 
|  | # | 
|  | #  - libs_section_prefix | 
|  | #  - libs_section_postfix | 
|  | #      The contents of these strings, if specified, will be placed around | 
|  | #      the libs section of the linker line. It allows one to inject libraries | 
|  | #      at the beginning and end for all targets in a toolchain. | 
|  | #  - solink_libs_section_prefix | 
|  | #  - solink_libs_section_postfix | 
|  | #      Same as libs_section_{pre,post}fix except used for solink instead of link. | 
|  | #  - link_outputs | 
|  | #      The content of this array, if specified, will be added to the list of | 
|  | #      outputs from the link command. This can be useful in conjunction with | 
|  | #      the post_link parameter. | 
|  | #  - use_unstripped_as_runtime_outputs | 
|  | #      When |strip| is set, mark unstripped executables as runtime deps rather | 
|  | #      than stripped ones. | 
|  | #  - post_link | 
|  | #      The content of this string, if specified, will be run as a separate | 
|  | #      command following the the link command. | 
|  | #  - deps | 
|  | #      Just forwarded to the toolchain definition. | 
|  | #  - executable_extension | 
|  | #      If this string is specified it will be used for the file extension | 
|  | #      for an executable, rather than using no extension; targets will | 
|  | #      still be able to override the extension using the output_extension | 
|  | #      variable. | 
|  | #  - rebuild_define | 
|  | #      The contents of this string, if specified, will be passed as a #define | 
|  | #      to the toolchain. It can be used to force recompiles whenever a | 
|  | #      toolchain is updated. | 
|  | #  - shlib_extension | 
|  | #      If this string is specified it will be used for the file extension | 
|  | #      for a shared library, rather than default value specified in | 
|  | #      toolchain.gni | 
|  | #  - strip | 
|  | #      Location of the strip executable. When specified, strip will be run on | 
|  | #      all shared libraries and executables as they are built. The pre-stripped | 
|  | #      artifacts will be put in lib.unstripped/ and exe.unstripped/. | 
|  | template("gcc_toolchain") { | 
|  | toolchain(target_name) { | 
|  | assert(defined(invoker.ar), "gcc_toolchain() must specify a \"ar\" value") | 
|  | assert(defined(invoker.cc), "gcc_toolchain() must specify a \"cc\" value") | 
|  | assert(defined(invoker.cxx), "gcc_toolchain() must specify a \"cxx\" value") | 
|  | assert(defined(invoker.ld), "gcc_toolchain() must specify a \"ld\" value") | 
|  |  | 
|  | # This define changes when the toolchain changes, forcing a rebuild. | 
|  | # Nothing should ever use this define. | 
|  | if (defined(invoker.rebuild_define)) { | 
|  | rebuild_string = "-D" + invoker.rebuild_define + " " | 
|  | } else { | 
|  | rebuild_string = "" | 
|  | } | 
|  |  | 
|  | # GN's syntax can't handle more than one scope dereference at once, like | 
|  | # "invoker.toolchain_args.foo", so make a temporary to hold the toolchain | 
|  | # args so we can do "invoker_toolchain_args.foo". | 
|  | assert(defined(invoker.toolchain_args), | 
|  | "Toolchains must specify toolchain_args") | 
|  | invoker_toolchain_args = invoker.toolchain_args | 
|  | assert(defined(invoker_toolchain_args.current_cpu), | 
|  | "toolchain_args must specify a current_cpu") | 
|  | assert(defined(invoker_toolchain_args.current_os), | 
|  | "toolchain_args must specify a current_os") | 
|  |  | 
|  | # When invoking this toolchain not as the default one, these args will be | 
|  | # passed to the build. They are ignored when this is the default toolchain. | 
|  | toolchain_args = { | 
|  | # Populate toolchain args from the invoker. | 
|  | forward_variables_from(invoker_toolchain_args, "*") | 
|  |  | 
|  | # The host toolchain value computed by the default toolchain's setup | 
|  | # needs to be passed through unchanged to all secondary toolchains to | 
|  | # ensure that it's always the same, regardless of the values that may be | 
|  | # set on those toolchains. | 
|  | host_toolchain = host_toolchain | 
|  |  | 
|  | if (!defined(invoker_toolchain_args.v8_current_cpu)) { | 
|  | v8_current_cpu = invoker_toolchain_args.current_cpu | 
|  | } | 
|  | } | 
|  |  | 
|  | # When the invoker has explicitly overridden use_goma or cc_wrapper in the | 
|  | # toolchain args, use those values, otherwise default to the global one. | 
|  | # This works because the only reasonable override that toolchains might | 
|  | # supply for these values are to force-disable them. | 
|  | if (defined(toolchain_args.use_goma)) { | 
|  | toolchain_uses_goma = toolchain_args.use_goma | 
|  | } else { | 
|  | toolchain_uses_goma = use_goma | 
|  | } | 
|  | if (defined(toolchain_args.cc_wrapper)) { | 
|  | toolchain_cc_wrapper = toolchain_args.cc_wrapper | 
|  | } else { | 
|  | toolchain_cc_wrapper = cc_wrapper | 
|  | } | 
|  | assert(!(toolchain_cc_wrapper != "" && toolchain_uses_goma), | 
|  | "Goma and cc_wrapper can't be used together.") | 
|  |  | 
|  | # When the invoker has explicitly overridden use_goma or cc_wrapper in the | 
|  | # toolchain args, use those values, otherwise default to the global one. | 
|  | # This works because the only reasonable override that toolchains might | 
|  | # supply for these values are to force-disable them. | 
|  | if (toolchain_uses_goma) { | 
|  | goma_path = "$goma_dir/gomacc" | 
|  |  | 
|  | # Use the static analysis script if static analysis is turned on | 
|  | # AND the tool has not opted out by setting | 
|  | # 'is_clang_static_analysis_supported' to false. | 
|  | if (is_clang && use_clang_static_analyzer && | 
|  | (!defined(invoker.is_clang_analysis_supported) || | 
|  | invoker.is_clang_analysis_supported)) { | 
|  | compiler_prefix = "${analyzer_wrapper} ${goma_path} " | 
|  |  | 
|  | # Create a distinct variable for "asm", since analysis runs pass | 
|  | # a bunch of flags to clang/clang++ that are nonsensical on assembler | 
|  | # runs. | 
|  | asm = "${goma_path} ${invoker.cc}" | 
|  | } else { | 
|  | compiler_prefix = "${goma_path} " | 
|  | } | 
|  | } else { | 
|  | if (is_clang && use_clang_static_analyzer && | 
|  | (!defined(invoker.is_clang_analysis_supported) || | 
|  | invoker.is_clang_analysis_supported)) { | 
|  | compiler_prefix = "${analyzer_wrapper} " | 
|  | asm = invoker.cc | 
|  | } else { | 
|  | compiler_prefix = "${toolchain_cc_wrapper} " | 
|  | } | 
|  | } | 
|  |  | 
|  | cc = compiler_prefix + invoker.cc | 
|  | cxx = compiler_prefix + invoker.cxx | 
|  | ar = invoker.ar | 
|  | ld = invoker.ld | 
|  | if (!defined(asm)) { | 
|  | asm = cc | 
|  | } | 
|  | if (defined(invoker.readelf)) { | 
|  | readelf = invoker.readelf | 
|  | } else { | 
|  | readelf = "readelf" | 
|  | } | 
|  | if (defined(invoker.nm)) { | 
|  | nm = invoker.nm | 
|  | } else { | 
|  | nm = "nm" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.shlib_extension)) { | 
|  | default_shlib_extension = invoker.shlib_extension | 
|  | } else { | 
|  | default_shlib_extension = shlib_extension | 
|  | } | 
|  |  | 
|  | if (defined(invoker.executable_extension)) { | 
|  | default_executable_extension = invoker.executable_extension | 
|  | } else { | 
|  | default_executable_extension = "" | 
|  | } | 
|  |  | 
|  | # Bring these into our scope for string interpolation with default values. | 
|  | if (defined(invoker.libs_section_prefix)) { | 
|  | libs_section_prefix = invoker.libs_section_prefix | 
|  | } else { | 
|  | libs_section_prefix = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.libs_section_postfix)) { | 
|  | libs_section_postfix = invoker.libs_section_postfix | 
|  | } else { | 
|  | libs_section_postfix = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.solink_libs_section_prefix)) { | 
|  | solink_libs_section_prefix = invoker.solink_libs_section_prefix | 
|  | } else { | 
|  | solink_libs_section_prefix = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.solink_libs_section_postfix)) { | 
|  | solink_libs_section_postfix = invoker.solink_libs_section_postfix | 
|  | } else { | 
|  | solink_libs_section_postfix = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.extra_cflags) && invoker.extra_cflags != "") { | 
|  | extra_cflags = " " + invoker.extra_cflags | 
|  | } else { | 
|  | extra_cflags = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.extra_cppflags) && invoker.extra_cppflags != "") { | 
|  | extra_cppflags = " " + invoker.extra_cppflags | 
|  | } else { | 
|  | extra_cppflags = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.extra_cxxflags) && invoker.extra_cxxflags != "") { | 
|  | extra_cxxflags = " " + invoker.extra_cxxflags | 
|  | } else { | 
|  | extra_cxxflags = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.extra_asmflags) && invoker.extra_asmflags != "") { | 
|  | extra_asmflags = " " + invoker.extra_asmflags | 
|  | } else { | 
|  | extra_asmflags = "" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.extra_ldflags) && invoker.extra_ldflags != "") { | 
|  | extra_ldflags = " " + invoker.extra_ldflags | 
|  | } else { | 
|  | extra_ldflags = "" | 
|  | } | 
|  |  | 
|  | enable_linker_map = defined(invoker.enable_linker_map) && | 
|  | invoker.enable_linker_map && generate_linker_map | 
|  |  | 
|  | # These library switches can apply to all tools below. | 
|  | lib_switch = "-l" | 
|  | lib_dir_switch = "-L" | 
|  |  | 
|  | # Object files go in this directory. | 
|  | object_subdir = "{{target_out_dir}}/{{label_name}}" | 
|  |  | 
|  | tool("cc") { | 
|  | depfile = "{{output}}.d" | 
|  | command = "$cc -MMD -MF $depfile ${rebuild_string}{{defines}} {{include_dirs}} {{cflags}} {{cflags_c}}${extra_cppflags}${extra_cflags} -c {{source}} -o {{output}}" | 
|  | depsformat = "gcc" | 
|  | description = "CC {{output}}" | 
|  | outputs = [ | 
|  | # The whitelist file is also an output, but ninja does not | 
|  | # currently support multiple outputs for tool("cc"). | 
|  | "$object_subdir/{{source_name_part}}.o", | 
|  | ] | 
|  | if (enable_resource_whitelist_generation) { | 
|  | compile_wrapper = | 
|  | rebase_path("//build/toolchain/gcc_compile_wrapper.py", | 
|  | root_build_dir) | 
|  | command = "$python_path \"$compile_wrapper\" --resource-whitelist=\"{{output}}.whitelist\" $command" | 
|  | } | 
|  | } | 
|  |  | 
|  | tool("cxx") { | 
|  | depfile = "{{output}}.d" | 
|  | command = "$cxx -MMD -MF $depfile ${rebuild_string}{{defines}} {{include_dirs}} {{cflags}} {{cflags_cc}}${extra_cppflags}${extra_cxxflags} -c {{source}} -o {{output}}" | 
|  | depsformat = "gcc" | 
|  | description = "CXX {{output}}" | 
|  | outputs = [ | 
|  | # The whitelist file is also an output, but ninja does not | 
|  | # currently support multiple outputs for tool("cxx"). | 
|  | "$object_subdir/{{source_name_part}}.o", | 
|  | ] | 
|  | if (enable_resource_whitelist_generation) { | 
|  | compile_wrapper = | 
|  | rebase_path("//build/toolchain/gcc_compile_wrapper.py", | 
|  | root_build_dir) | 
|  | command = "$python_path \"$compile_wrapper\" --resource-whitelist=\"{{output}}.whitelist\" $command" | 
|  | } | 
|  | } | 
|  |  | 
|  | tool("asm") { | 
|  | # For GCC we can just use the C compiler to compile assembly. | 
|  | depfile = "{{output}}.d" | 
|  | command = "$asm -MMD -MF $depfile ${rebuild_string}{{defines}} {{include_dirs}} {{asmflags}}${extra_asmflags} -c {{source}} -o {{output}}" | 
|  | depsformat = "gcc" | 
|  | description = "ASM {{output}}" | 
|  | outputs = [ | 
|  | "$object_subdir/{{source_name_part}}.o", | 
|  | ] | 
|  | } | 
|  |  | 
|  | tool("alink") { | 
|  | rspfile = "{{output}}.rsp" | 
|  | whitelist_flag = " " | 
|  | if (enable_resource_whitelist_generation) { | 
|  | whitelist_flag = " --resource-whitelist=\"{{output}}.whitelist\"" | 
|  | } | 
|  |  | 
|  | # This needs a Python script to avoid using simple sh features in this | 
|  | # command, in case the host does not use a POSIX shell (e.g. compiling | 
|  | # POSIX-like toolchains such as NaCl on Windows). | 
|  | ar_wrapper = | 
|  | rebase_path("//build/toolchain/gcc_ar_wrapper.py", root_build_dir) | 
|  |  | 
|  | if (current_os == "aix") { | 
|  | # We use slightly different arflags for AIX. | 
|  | extra_arflags = "-r -c -s" | 
|  | } else { | 
|  | extra_arflags = "-r -c -s -D" | 
|  | } | 
|  |  | 
|  | # Almost all targets build with //build/config/compiler:thin_archive which | 
|  | # adds -T to arflags. | 
|  | command = "$python_path \"$ar_wrapper\"$whitelist_flag --output={{output}} --ar=\"$ar\" \"{{arflags}} $extra_arflags\" @\"$rspfile\"" | 
|  | description = "AR {{output}}" | 
|  | rspfile_content = "{{inputs}}" | 
|  | outputs = [ | 
|  | "{{output_dir}}/{{target_output_name}}{{output_extension}}", | 
|  | ] | 
|  |  | 
|  | # Shared libraries go in the target out directory by default so we can | 
|  | # generate different targets with the same name and not have them collide. | 
|  | default_output_dir = "{{target_out_dir}}" | 
|  | default_output_extension = ".a" | 
|  | output_prefix = "lib" | 
|  | } | 
|  |  | 
|  | tool("solink") { | 
|  | soname = "{{target_output_name}}{{output_extension}}"  # e.g. "libfoo.so". | 
|  | sofile = "{{output_dir}}/$soname"  # Possibly including toolchain dir. | 
|  | rspfile = sofile + ".rsp" | 
|  | pool = "//build/toolchain:link_pool($default_toolchain)" | 
|  | whitelist_flag = " " | 
|  | if (enable_resource_whitelist_generation) { | 
|  | whitelist_file = "$sofile.whitelist" | 
|  | whitelist_flag = " --resource-whitelist=\"$whitelist_file\"" | 
|  | } | 
|  |  | 
|  | if (defined(invoker.strip)) { | 
|  | unstripped_sofile = "{{root_out_dir}}/lib.unstripped/$soname" | 
|  | } else { | 
|  | unstripped_sofile = sofile | 
|  | } | 
|  |  | 
|  | # These variables are not built into GN but are helpers that | 
|  | # implement (1) linking to produce a .so, (2) extracting the symbols | 
|  | # from that file (3) if the extracted list differs from the existing | 
|  | # .TOC file, overwrite it, otherwise, don't change it. | 
|  | tocfile = sofile + ".TOC" | 
|  |  | 
|  | link_command = "$ld -shared {{ldflags}}${extra_ldflags} -o \"$unstripped_sofile\" -Wl,-soname=\"$soname\" @\"$rspfile\"" | 
|  |  | 
|  | # Generate a map file to be used for binary size analysis. | 
|  | # Map file adds ~10% to the link time on a z620. | 
|  | # With target_os="android", libchrome.so.map.gz is ~20MB. | 
|  | map_switch = "" | 
|  | if (enable_linker_map && is_official_build) { | 
|  | map_file = "$unstripped_sofile.map.gz" | 
|  | map_switch = " --map-file \"$map_file\"" | 
|  | } | 
|  |  | 
|  | assert(defined(readelf), "to solink you must have a readelf") | 
|  | assert(defined(nm), "to solink you must have an nm") | 
|  | strip_switch = "" | 
|  | if (defined(invoker.strip)) { | 
|  | strip_switch = "--strip=${invoker.strip} " | 
|  | } | 
|  |  | 
|  | # This needs a Python script to avoid using a complex shell command | 
|  | # requiring sh control structures, pipelines, and POSIX utilities. | 
|  | # The host might not have a POSIX shell and utilities (e.g. Windows). | 
|  | solink_wrapper = | 
|  | rebase_path("//build/toolchain/gcc_solink_wrapper.py", root_build_dir) | 
|  | command = "$python_path \"$solink_wrapper\" --readelf=\"$readelf\" --nm=\"$nm\" $strip_switch--sofile=\"$unstripped_sofile\" --tocfile=\"$tocfile\"$map_switch --output=\"$sofile\"$whitelist_flag -- $link_command" | 
|  |  | 
|  | if (target_cpu == "mipsel" && is_component_build && is_android) { | 
|  | rspfile_content = "-Wl,--start-group -Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive $solink_libs_section_prefix {{libs}} $solink_libs_section_postfix -Wl,--end-group" | 
|  | } else { | 
|  | rspfile_content = "-Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive $solink_libs_section_prefix {{libs}} $solink_libs_section_postfix" | 
|  | } | 
|  |  | 
|  | description = "SOLINK $sofile" | 
|  |  | 
|  | # Use this for {{output_extension}} expansions unless a target manually | 
|  | # overrides it (in which case {{output_extension}} will be what the target | 
|  | # specifies). | 
|  | default_output_extension = default_shlib_extension | 
|  |  | 
|  | default_output_dir = "{{root_out_dir}}" | 
|  | if (shlib_subdir != ".") { | 
|  | default_output_dir += "/$shlib_subdir" | 
|  | } | 
|  |  | 
|  | output_prefix = "lib" | 
|  |  | 
|  | # Since the above commands only updates the .TOC file when it changes, ask | 
|  | # Ninja to check if the timestamp actually changed to know if downstream | 
|  | # dependencies should be recompiled. | 
|  | restat = true | 
|  |  | 
|  | # Tell GN about the output files. It will link to the sofile but use the | 
|  | # tocfile for dependency management. | 
|  | outputs = [ | 
|  | sofile, | 
|  | tocfile, | 
|  | ] | 
|  | if (enable_resource_whitelist_generation) { | 
|  | outputs += [ whitelist_file ] | 
|  | } | 
|  | if (sofile != unstripped_sofile) { | 
|  | outputs += [ unstripped_sofile ] | 
|  | if (defined(invoker.use_unstripped_as_runtime_outputs) && | 
|  | invoker.use_unstripped_as_runtime_outputs) { | 
|  | runtime_outputs = [ unstripped_sofile ] | 
|  | } | 
|  | } | 
|  | if (defined(map_file)) { | 
|  | outputs += [ map_file ] | 
|  | } | 
|  | link_output = sofile | 
|  | depend_output = tocfile | 
|  | } | 
|  |  | 
|  | tool("solink_module") { | 
|  | soname = "{{target_output_name}}{{output_extension}}"  # e.g. "libfoo.so". | 
|  | sofile = "{{output_dir}}/$soname" | 
|  | rspfile = sofile + ".rsp" | 
|  | pool = "//build/toolchain:link_pool($default_toolchain)" | 
|  |  | 
|  | if (defined(invoker.strip)) { | 
|  | unstripped_sofile = "{{root_out_dir}}/lib.unstripped/$soname" | 
|  | } else { | 
|  | unstripped_sofile = sofile | 
|  | } | 
|  |  | 
|  | command = "$ld -shared {{ldflags}}${extra_ldflags} -o \"$unstripped_sofile\" -Wl,-soname=\"$soname\" @\"$rspfile\"" | 
|  |  | 
|  | if (defined(invoker.strip)) { | 
|  | strip_command = "${invoker.strip} -o \"$sofile\" \"$unstripped_sofile\"" | 
|  | command += " && " + strip_command | 
|  | } | 
|  | rspfile_content = "-Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive $solink_libs_section_prefix {{libs}} $solink_libs_section_postfix" | 
|  |  | 
|  | description = "SOLINK_MODULE $sofile" | 
|  |  | 
|  | # Use this for {{output_extension}} expansions unless a target manually | 
|  | # overrides it (in which case {{output_extension}} will be what the target | 
|  | # specifies). | 
|  | if (defined(invoker.loadable_module_extension)) { | 
|  | default_output_extension = invoker.loadable_module_extension | 
|  | } else { | 
|  | default_output_extension = default_shlib_extension | 
|  | } | 
|  |  | 
|  | default_output_dir = "{{root_out_dir}}" | 
|  | if (shlib_subdir != ".") { | 
|  | default_output_dir += "/$shlib_subdir" | 
|  | } | 
|  |  | 
|  | output_prefix = "lib" | 
|  |  | 
|  | outputs = [ | 
|  | sofile, | 
|  | ] | 
|  | if (sofile != unstripped_sofile) { | 
|  | outputs += [ unstripped_sofile ] | 
|  | if (defined(invoker.use_unstripped_as_runtime_outputs) && | 
|  | invoker.use_unstripped_as_runtime_outputs) { | 
|  | runtime_outputs = [ unstripped_sofile ] | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | tool("link") { | 
|  | exename = "{{target_output_name}}{{output_extension}}" | 
|  | outfile = "{{output_dir}}/$exename" | 
|  | rspfile = "$outfile.rsp" | 
|  | unstripped_outfile = outfile | 
|  | pool = "//build/toolchain:link_pool($default_toolchain)" | 
|  |  | 
|  | # Use this for {{output_extension}} expansions unless a target manually | 
|  | # overrides it (in which case {{output_extension}} will be what the target | 
|  | # specifies). | 
|  | default_output_extension = default_executable_extension | 
|  |  | 
|  | default_output_dir = "{{root_out_dir}}" | 
|  |  | 
|  | if (defined(invoker.strip)) { | 
|  | unstripped_outfile = "{{root_out_dir}}/exe.unstripped/$exename" | 
|  | } | 
|  |  | 
|  | # Generate a map file to be used for binary size analysis. | 
|  | # Map file adds ~10% to the link time on a z620. | 
|  | # With target_os="android", libchrome.so.map.gz is ~20MB. | 
|  | map_switch = "" | 
|  | if (enable_linker_map && is_official_build) { | 
|  | map_file = "$unstripped_outfile.map.gz" | 
|  | map_switch = " --map-file \"$map_file\"" | 
|  | } | 
|  |  | 
|  | start_group_flag = "" | 
|  | end_group_flag = "" | 
|  | if (current_os != "aix") { | 
|  | # the "--start-group .. --end-group" feature isn't available on the aix ld. | 
|  | start_group_flag = "-Wl,--start-group" | 
|  | end_group_flag = "-Wl,--end-group " | 
|  | } | 
|  | link_command = "$ld {{ldflags}}${extra_ldflags} -o \"$unstripped_outfile\" $start_group_flag @\"$rspfile\" {{solibs}} $end_group_flag $libs_section_prefix {{libs}} $libs_section_postfix" | 
|  |  | 
|  | strip_switch = "" | 
|  |  | 
|  | if (defined(invoker.strip)) { | 
|  | strip_switch = " --strip=\"${invoker.strip}\" --unstripped-file=\"$unstripped_outfile\"" | 
|  | } | 
|  |  | 
|  | link_wrapper = | 
|  | rebase_path("//build/toolchain/gcc_link_wrapper.py", root_build_dir) | 
|  | command = "$python_path \"$link_wrapper\" --output=\"$outfile\"$strip_switch$map_switch -- $link_command" | 
|  | description = "LINK $outfile" | 
|  | rspfile_content = "{{inputs}}" | 
|  | outputs = [ | 
|  | outfile, | 
|  | ] | 
|  | if (outfile != unstripped_outfile) { | 
|  | outputs += [ unstripped_outfile ] | 
|  | if (defined(invoker.use_unstripped_as_runtime_outputs) && | 
|  | invoker.use_unstripped_as_runtime_outputs) { | 
|  | runtime_outputs = [ unstripped_outfile ] | 
|  | } | 
|  | } | 
|  | if (defined(invoker.link_outputs)) { | 
|  | outputs += invoker.link_outputs | 
|  | } | 
|  | if (defined(map_file)) { | 
|  | outputs += [ map_file ] | 
|  | } | 
|  | } | 
|  |  | 
|  | # These two are really entirely generic, but have to be repeated in | 
|  | # each toolchain because GN doesn't allow a template to be used here. | 
|  | # See //build/toolchain/toolchain.gni for details. | 
|  | tool("stamp") { | 
|  | command = stamp_command | 
|  | description = stamp_description | 
|  | } | 
|  | tool("copy") { | 
|  | command = copy_command | 
|  | description = copy_description | 
|  | } | 
|  |  | 
|  | tool("action") { | 
|  | pool = "//build/toolchain:action_pool($default_toolchain)" | 
|  | } | 
|  |  | 
|  | forward_variables_from(invoker, [ "deps" ]) | 
|  | } | 
|  | } | 
|  |  | 
|  | # This is a shorthand for gcc_toolchain instances based on the Chromium-built | 
|  | # version of Clang. Only the toolchain_cpu and toolchain_os variables need to | 
|  | # be specified by the invoker, and optionally toolprefix if it's a | 
|  | # cross-compile case. Note that for a cross-compile case this toolchain | 
|  | # requires a config to pass the appropriate -target option, or else it will | 
|  | # actually just be doing a native compile. The invoker can optionally override | 
|  | # use_gold too. | 
|  | template("clang_toolchain") { | 
|  | if (defined(invoker.toolprefix)) { | 
|  | toolprefix = invoker.toolprefix | 
|  | } else { | 
|  | toolprefix = "" | 
|  | } | 
|  |  | 
|  | gcc_toolchain(target_name) { | 
|  | prefix = rebase_path("$clang_base_path/bin", root_build_dir) | 
|  | cc = "$prefix/clang" | 
|  | cxx = "$prefix/clang++" | 
|  | ld = cxx | 
|  | readelf = "${toolprefix}readelf" | 
|  | ar = "${prefix}/llvm-ar" | 
|  | nm = "${toolprefix}nm" | 
|  |  | 
|  | forward_variables_from(invoker, | 
|  | [ | 
|  | "strip", | 
|  | "is_clang_analysis_supported", | 
|  | "enable_linker_map", | 
|  | "use_unstripped_as_runtime_outputs", | 
|  | ]) | 
|  |  | 
|  | toolchain_args = { | 
|  | if (defined(invoker.toolchain_args)) { | 
|  | forward_variables_from(invoker.toolchain_args, "*") | 
|  | } | 
|  | is_clang = true | 
|  | } | 
|  | } | 
|  | } |