blob: 5b785a5191ff3b7c3bb521c77779bd96b640cefa [file] [log] [blame]
# Copyright 2020 The Pigweed Authors
#
# 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
#
# https://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("//build_overrides/pigweed.gni")
import("$dir_pw_build/cc_blob_library.gni")
import("$dir_pw_build/python.gni")
import("$dir_pw_build/relative_source_file_names.gni")
import("$dir_pw_docgen/docs.gni")
import("$dir_pw_toolchain/generate_toolchain.gni")
import("$dir_pw_toolchain/traits.gni")
import("$dir_pw_unit_test/test.gni")
import("target_types.gni")
# IMPORTANT: The compilation flags in this file must be kept in sync with
# the CMake flags pw_build/CMakeLists.txt.
# TODO: b/301262374 - Provide a better way to detect the compiler type.
is_clang = defined(pw_toolchain_SCOPE.cc) &&
get_path_info(pw_toolchain_SCOPE.cc, "file") == "clang"
config("colorize_output") {
if (pw_build_COLORIZE_OUTPUT) {
cflags = [
# Colorize output. Ninja's Clang invocation disables color by default.
"-fdiagnostics-color",
]
ldflags = cflags
}
}
config("debugging") {
# Enable debug symbol generation. This has no effect on final code size.
cflags = [ "-g" ]
}
config("extra_debugging") {
# Include things like macro expansion in debug info.
cflags = [ "-g3" ]
}
# Optimization levels
config("optimize_debugging") {
cflags = [ "-Og" ]
ldflags = cflags
}
config("optimize_speed") {
cflags = [ "-O2" ]
ldflags = cflags
}
config("optimize_more_speed") {
cflags = [ "-O3" ]
ldflags = cflags
}
config("optimize_size") {
cflags = [ "-Os" ]
ldflags = cflags
}
config("enable_clang_fixed_point_types") {
if (is_clang) {
cflags = [ "-ffixed-point" ]
}
}
config("enable_clang_mlinliner") {
cflags = [
# Enable ML inliner.
"-mllvm",
"-enable-ml-inliner=release",
]
}
config("enable_clang_gvn_sink_hoist") {
cflags = [
# Enable GVN sink/hoist.
"-mllvm",
"-enable-gvn-sink=1",
"-mllvm",
"-enable-gvn-hoist=1",
]
}
config("optimize_size_clang") {
cflags = [ "-Oz" ]
ldflags = [
# Identical Code Folding optimization
"-Wl,--icf=all",
# LLD does not recognize `Oz` which is a compiler front-end flag.
"-Wl,-O2",
]
ldflags += cflags
}
# Standard compiler flags to reduce output binary size.
config("reduced_size") {
cflags = [
"-fno-common",
"-fno-exceptions",
"-ffunction-sections",
"-fdata-sections",
"-fomit-frame-pointer",
]
cflags_cc = [ "-fno-rtti" ]
if (current_os == "mac" || current_os == "ios") {
# Delete unreferenced sections. Helpful with -ffunction-sections.
ldflags = [ "-Wl,-dead_strip" ]
} else {
# Delete unreferenced sections. Helpful with -ffunction-sections.
ldflags = [ "-Wl,--gc-sections" ]
}
}
config("rust_edition_2015") {
rustflags = [ "--edition=2015" ]
}
config("rust_edition_2018") {
rustflags = [ "--edition=2018" ]
}
config("rust_edition_2021") {
rustflags = [ "--edition=2021" ]
}
config("strict_warnings") {
cflags = [
"-Wall",
"-Wextra",
"-Wimplicit-fallthrough",
"-Wcast-qual",
"-Wundef",
"-Wpointer-arith",
# Make all warnings errors, except for the exemptions below.
"-Werror",
"-Wno-error=cpp", # preprocessor #warning statement
"-Wno-error=deprecated-declarations", # [[deprecated]] attribute
]
cflags_cc = [ "-Wnon-virtual-dtor" ]
}
# Thread safety warnings are only supported by Clang.
config("clang_thread_safety_warnings") {
cflags = [ "-Wthread-safety" ]
defines = [ "_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS=1" ]
}
# This config contains warnings that we don't necessarily recommend projects
# enable, but are enabled for upstream Pigweed for maximum project
# compatibility.
config("extra_strict_warnings") {
cflags = [
"-Wshadow",
"-Wredundant-decls",
]
cflags_c = [ "-Wstrict-prototypes" ]
}
# This config contains warnings that are enabled for upstream Pigweed.
# This config MUST NOT be used downstream to allow for warnings to be
# added in the future without breaking downstream.
config("internal_strict_warnings") {
cflags = [ "-Wswitch-enum" ]
if (is_clang) {
cflags += [ "-Wextra-semi" ]
} else {
# TODO: b/306734552 - On GCC, this only works as a C++ flag.
cflags_cc = [ "-Wextra-semi" ]
}
# TODO: b/243069432 - Enable pedantic warnings on Windows when they pass.
if (host_os != "win") {
configs = [ ":pedantic_warnings" ]
}
}
config("pedantic_warnings") {
cflags = [
# Enable -Wpedantic, but disable a few warnings.
"-Wpedantic",
# Allow designated initializers, which were added in C++20 but widely
# supported prior and permitted by the Google style guide.
"-Wno-c++20-designator",
# Allow empty ... arguments in macros, which are permitted in C++20 but
# widely supported prior.
"-Wno-gnu-zero-variadic-macro-arguments",
]
if (pw_toolchain_CXX_STANDARD < pw_toolchain_STANDARD.CXX17) {
# Allow C++17 attributes in C++14, since Pigweed targets C++17 or newer.
cflags += [ "-Wno-c++17-attribute-extensions" ]
}
# TODO: b/333712899 - Enable C23 extension warnings.
cflags += [ "-Wno-c23-extensions" ]
# TODO: b/335021928 - Enable C++ 20 extension warnings.
cflags += [ "-Wno-c++20-extensions" ]
# TODO: b/335328444 - Enable C++ 20 extension warnings.
cflags += [ "-Wno-deprecated-pragma" ]
}
# Numeric conversion warnings.
#
# Originally Pigweed didn't enable this, but we ultimately decided to turn it
# on since it caused issues with downstream project that enable this warning.
#
# b/259746255 tracks converting everything to build with this warning.
config("conversion_warnings") {
# TODO: b/260629756 - Remove Windows restriction once fixed for Windows + GCC.
if (host_os != "win") {
cflags = [ "-Wconversion" ]
}
}
config("cpp14") {
cflags_cc = [ "-std=c++14" ]
}
config("cpp17") {
cflags_cc = [
"-std=c++17",
# Allow uses of the register keyword, which may appear in C headers.
"-Wno-register",
]
}
config("cpp20") {
cflags_cc = [
"-std=c++20",
"-Wno-register",
]
}
# Selects the C++ standard to used based on the pw_toolchain_CXX_STANDARD
# toolchain trait.
config("toolchain_cpp_standard") {
if (pw_toolchain_CXX_STANDARD == pw_toolchain_STANDARD.CXX14) {
configs = [ ":cpp14" ]
} else if (pw_toolchain_CXX_STANDARD == pw_toolchain_STANDARD.CXX17) {
configs = [ ":cpp17" ]
} else if (pw_toolchain_CXX_STANDARD == pw_toolchain_STANDARD.CXX20) {
configs = [ ":cpp20" ]
} else {
assert(false,
"Unexpected pw_toolchain_CXX_STANDARD value: " +
pw_toolchain_CXX_STANDARD)
}
}
# Removes system-dependent prefixes from macros like __FILE__ and debug symbols.
#
# All compilation is relative to root_build_dir. The root_build_dir path is
# arbitrary, so it must be removed to make builds reproducible. This config
# remaps paths as if compilation occurred from the repository root instead of
# root_build_dir. Paths that include root_build_dir are updated to standardize
# on out/ as the build directory.
#
# If an ELF is built from a directory other than "out/", debuggers will be able
# to locate in-tree sources, but may have issues finding generated sources in
# the output directory. This can be worked around in a few ways:
#
# - Use GDB's `set substitute-path <from> <to>` option to remap paths.
# - Rebuild from out/.
# - Symlink out/ to the build directory.
# - Temporarily disable these transformations.
#
# If an ELF is built from "out/", debuggers will be able to locate all sources,
# including generated sources, when run from the repo root.
config("relative_paths") {
# Apply a series of file-prefix-map transformations. Only the first matching
# option applies.
#
# GCC applies these in reverse order due to building iterating through a
# recursively constructed linked list:
# inclusive-language: disable
# https://github.com/gcc-mirror/gcc/blob/master/gcc/file-prefix-map.cc#L41.
# inclusive-language: enable
#
# Clang currently does not have a set forwards or backwards application order
# due to storing them in a std::map (that reorders lexicogrpahically by key):
# https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Basic/CodeGenOptions.h#L209.
#
# TODO: b/278906020 - Tracks merging in an upstream change to LLVM to that will
# enforce clang applying these transformations in order. Until then, there
# will be issues with the debug and coverage information while using build
# directories that are more than a single directory from the root project
# directory. This is due to "=out/" always being applied first due to the
# left-hand side of the = being "", which is always ordered first in the
# std::map.
_transformations = [
# Remap absolute prefixes for files in the output directory to out/.
rebase_path(root_build_dir) + "/=out/",
# Remove the path to the out directory so the ELF is relative to the root.
rebase_path(root_build_dir) + "=",
# Remove any absolute paths to the repo root.
rebase_path("//") + "=",
# Remove the relative path from the build directory to the root, which is
# the prefix of in-tree sources.
rebase_path("//", root_build_dir) + "=",
# Prepend out/ to any unmatched files, which are in the output directory.
"=out/",
# Repeat the replacements in reverse order since GCC applies them backwards.
rebase_path("//", root_build_dir) + "=",
rebase_path("//") + "=",
rebase_path(root_build_dir) + "=",
rebase_path(root_build_dir) + "/=out/",
]
cflags = []
foreach(transform, _transformations) {
cflags += [ "-ffile-prefix-map=" + transform ]
}
# Write the transformations to a well known path so that other utilities
# that need to present file names that match the compiler's __FILE__
# macro can apply the same transformation.
write_file(pw_build_RELATIVE_PATH_TRANSFORM_JSON, _transformations, "json")
}
# This group is linked into all pw_executable, pw_static_library, and
# pw_shared_library targets. This makes it possible to ensure symbols are
# defined without a dependency on them.
#
# pw_build_LINK_DEPS should only be used when necessary. For example,
# pw_assert relies on pw_build_LINK_DEPS to avoid circular dependencies
# in GN. In almost all other cases, build targets should explicitly depend on
# the other targets they use.
#
# pw_build_TOOLCHAIN_LINK_DEPS is used to define dependencies introduced by
# the various toolchains created under pw_toolchain module in GN. For example,
# LLVM compiler-rt builtin libraries, or the arm-none-eabi newlib interface
# stubs.
group("link_deps") {
deps = pw_build_LINK_DEPS + pw_build_TOOLCHAIN_LINK_DEPS
}
# This empty target is used as the default value for module configurations.
# Projects may set pw_build_DEFAULT_MODULE_CONFIG to a different GN target that
# overrides modules' configuration options via macro definitions or a header
# forcibly included with `-include`.
group("empty") {
}
config("default_config") {
include_dirs = [ "public" ]
}
# Linker script utility PW_MUST_PLACE
pw_source_set("must_place") {
public_configs = [ ":default_config" ]
public = [ "public/pw_build/must_place.ld.h" ]
}
pw_doc_group("docs") {
sources = [
"bazel.rst",
"cmake.rst",
"docs.rst",
"gn.rst",
"linker_scripts.rst",
"project_builder.rst",
"python.rst",
]
}
config("module_config_test_config") {
visibility = [ ":*" ]
defines = [ "PW_THREAD_FREERTOS_CONFIG_JOINING_ENABLED=1" ]
}
# Pigweed upstream does not use the default toolchain, but other projects may
# use it. To support using pw_build from the default toolchain without fully
# configuring the Pigweed build, only instantiate the pw_build tests for a
# non-default toolchain.
if (current_toolchain != default_toolchain) {
pw_test("cc_blob_library_test") {
sources = [ "cc_blob_library_test.cc" ]
deps = [ ":test_blob" ]
}
pw_test("module_config_test") {
public_configs = [ ":module_config_test_config" ]
sources = [ "module_config_test.cc" ]
deps = [ "$dir_pw_thread_freertos:config" ]
}
pw_cc_blob_library("test_blob") {
out_header = "pw_build/test_blob.h"
namespace = "test::ns"
blobs = [
{
file_path = "test_blob_0123.bin"
symbol_name = "kFirstBlob0123"
alignas = 512
},
{
file_path = "test_blob_0123.bin"
symbol_name = "kSecondBlob0123"
},
]
visibility = [ ":*" ]
}
# file_prefix_map_test verifies that the -ffile-prefix-map option is applied
# correctly.
# File paths should be relative to the root of the GN build.
_test_header = rebase_path("pw_build_private/file_prefix_map_test.h", "//")
_path_test_define = [ "PW_BUILD_EXPECTED_HEADER_PATH=\"$_test_header\"" ]
pw_test("file_prefix_map_test") {
_source_path = rebase_path("file_prefix_map_test.cc", "//")
sources = [ "file_prefix_map_test.cc" ]
defines = _path_test_define +
[ "PW_BUILD_EXPECTED_SOURCE_PATH=\"$_source_path\"" ]
deps = [ ":file_prefix_map_generated_file" ]
}
# Generated file paths should be relative to the build directory.
copy("generate_file_prefix_map_test_source") {
sources = [ "file_prefix_map_test.cc" ]
outputs = [ get_label_info(":file_prefix_map_test", "target_gen_dir") +
"/file_prefix_map_test_generated.cc" ]
visibility = [ ":*" ]
}
pw_source_set("file_prefix_map_generated_file") {
public = [ "pw_build_private/file_prefix_map_test.h" ]
sources = get_target_outputs(":generate_file_prefix_map_test_source")
deps = [ ":generate_file_prefix_map_test_source" ]
_source_path = rebase_path(sources[0], root_build_dir)
# The source file is prefixed with out/ since it's generated.
defines = _path_test_define +
[ "PW_BUILD_EXPECTED_SOURCE_PATH=\"out/$_source_path\"" ]
include_dirs = [ "." ] # Allow accessing file_prefix_map_test.h
visibility = [ ":*" ]
}
pw_source_set("empty_main") {
sources = [ "empty_main.cc" ]
visibility = [ ":*" ]
}
pw_test_group("tests") {
tests = [
":cc_blob_library_test",
":file_prefix_map_test",
]
}
}