build/config/compiler.gni

# Copyright 2018 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

if (is_debug) {
  # TODO(https://fxbug.dev/42170458): consider "debug"
  default_optimize = "none"
} else {
  default_optimize = "size"
}

# NOTE: Keep in sync with //build/config/zircon/levels.gni
declare_args() {
  # * `none`: really unoptimized, usually only build-tested and not run
  # * `debug`: "optimized for debugging", light enough to avoid confusion
  # * `default`: default optimization level
  # * `size`:  optimized for space rather than purely for speed
  # * `size_lto`:  optimize for space and use LTO
  # * `speed`: optimized purely for speed
  # * `sanitizer`: optimized for sanitizers (ASan, etc.)
  # * `profile`: optimized for coverage/profile data collection
  # * `coverage`: optimized for coverage data collection
  optimize = default_optimize
}

_optimize_valid = [
  "none",
  "debug",
  "default",
  "size",
  "size_lto",
  "speed",
  "sanitizer",
  "profile",
  "coverage",
]

assert(_optimize_valid + [ optimize ] - [ optimize ] != _optimize_valid,
       "`optimize=\"...\"` must be one of $_optimize_valid")

declare_args() {
  # Controls whether to use -Oz when `optimize` is set to `"size"`.
  use_oz = false
}

if (use_oz) {
  assert(optimize == "size", "clang_use_oz requires `optimize = \"size\"`")
}

declare_args() {
  # * `none` means no debugging information
  # * `backtrace` means sufficient debugging information to symbolize backtraces
  # * `debug` means debugging information suited for debugging
  debuginfo = "debug"
}

_debuginfo_valid = [
  "none",
  "backtrace",
  "debug",
]

assert(_debuginfo_valid + [ debuginfo ] - [ debuginfo ] != _debuginfo_valid,
       "`debuginfo=\"...\"` must be one of $_debuginfo_valid")

declare_args() {
  # Explicitly specify DWARF version used.
  dwarf_version = 5

  # TODO(https://fxbug.dev/42101274): Use DWARF 4 for the kernel proper and physboot
  # until the GDB used by kernel developers fully supports DWARF 5.
  # TODO(https://fxbug.dev/42168542): Use DWARF 4 on macOS to avoid the warning reported
  # by lld. This matches the default DWARF version currently used by Clang:
  # https://github.com/llvm/llvm-project/blob/89c94c2/clang/lib/Driver/ToolChains/Darwin.cpp#L1159
  if (is_kernel || is_mac) {
    dwarf_version = 4
  }
}

assert(dwarf_version >= 2 && dwarf_version <= 5,
       "`dwarf_version=\"...\"` must be between 2 and 5")

if (is_gcc) {
  # TODO(https://fxbug.dev/42076979): GCC doesn't yet support zstd.
  default_compress_debuginfo = "zlib"
} else {
  default_compress_debuginfo = "zstd"
}

declare_args() {
  # Enable compression of debug sections.
  compress_debuginfo = default_compress_debuginfo
}

_compress_debuginfo_valid = [
  "none",
  "zlib",
  "zstd",
]

assert(_compress_debuginfo_valid + [ compress_debuginfo ] -
           [ compress_debuginfo ] != _compress_debuginfo_valid,
       "`compress_debuginfo=\"...\"` must be one of $_compress_debuginfo_valid")