blob: 2b169824791a87b69d1a46d0e93c30f5a82f28e2 [file] [log] [blame]
# Copyright 2019 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.
load("@rules_cc//cc:defs.bzl", "cc_library")
"""Pigweed build environment for bazel."""
DEBUGGING = [
"-g",
]
# Standard compiler flags to reduce output binary size.
REDUCED_SIZE_COPTS = [
"-fno-common",
"-fno-exceptions",
"-ffunction-sections",
"-fdata-sections",
]
STRICT_WARNINGS_COPTS = [
"-Wall",
"-Wextra",
# Make all warnings errors, except for the exemptions below.
"-Werror",
"-Wno-error=cpp", # preprocessor #warning statement
"-Wno-error=deprecated-declarations", # [[deprecated]] attribute
]
CPP17_COPTS = [
"-std=c++17",
"-fno-rtti",
"-Wnon-virtual-dtor",
# Allow uses of the register keyword, which may appear in C headers.
"-Wno-register",
]
DISABLE_PENDING_WORKAROUND_COPTS = [
"-Wno-private-header",
]
PW_DEFAULT_COPTS = (
DEBUGGING +
REDUCED_SIZE_COPTS +
STRICT_WARNINGS_COPTS +
DISABLE_PENDING_WORKAROUND_COPTS
)
KYTHE_COPTS = [
"-Wno-unknown-warning-option",
]
PW_DEFAULT_LINKOPTS = []
def _add_defaults(kwargs):
"""Adds default arguments suitable for both C and C++ code to kwargs."""
copts = kwargs.get("copts", []) + PW_DEFAULT_COPTS
kwargs["copts"] = select({
"//pw_build:kythe": copts + KYTHE_COPTS,
"//conditions:default": copts,
})
kwargs["linkopts"] = kwargs.get("linkopts", []) + PW_DEFAULT_LINKOPTS
# Set linkstatic to avoid building .so files.
kwargs["linkstatic"] = True
kwargs.setdefault("features", [])
# Crosstool--adding this line to features disables header modules, which
# don't work with -fno-rtti. Note: this is not a command-line argument,
# it's "minus use_header_modules".
kwargs["features"].append("-use_header_modules")
def _default_cc_and_c_kwargs(kwargs):
_add_defaults(kwargs)
kwargs.setdefault("srcs", [])
cc = dict(kwargs.items())
cc["srcs"] = [src for src in kwargs["srcs"] if not src.endswith(".c")]
cc["copts"] = cc["copts"] + CPP17_COPTS
c_srcs = [src for src in kwargs["srcs"] if src.endswith(".c")]
if c_srcs:
c = dict(kwargs.items())
c["name"] += "_c"
c["srcs"] = c_srcs + [src for src in kwargs["srcs"] if src.endswith(".h")]
cc["deps"] = cc.get("deps", []) + [":" + c["name"]]
return cc, c
return cc, None
def _add_cc_and_c_targets(target, kwargs):
cc_kwargs, c_kwargs = _default_cc_and_c_kwargs(kwargs)
if c_kwargs:
cc_library(**c_kwargs)
target(**cc_kwargs)
def pw_cc_binary(**kwargs):
_add_cc_and_c_targets(native.cc_binary, kwargs)
def pw_cc_library(**kwargs):
_add_cc_and_c_targets(native.cc_library, kwargs)
def pw_cc_test(**kwargs):
kwargs["deps"] = kwargs.get("deps", []) + ["//pw_unit_test:main"]
_add_cc_and_c_targets(native.cc_test, kwargs)
def pw_cc_facade(**kwargs):
# Bazel facades should be source only cc_library's this is to simplify
# lazy header evaluation. Bazel headers are not 'precompiled' so the build
# system does not check to see if the build has the right dependant headers
# in the sandbox. If a source file is declared here and includes a header
# file the toolchain will compile as normal and complain about the missing
# backend headers.
if "srcs" in kwargs.keys():
fail("'srcs' attribute does not exist in pw_cc_facade, please use \
main implementing target.")
_add_cc_and_c_targets(native.cc_library, kwargs)