Remove enable_frame_pointers and enable frame-pointers under ChromeOS.

build/config/compiler/compiler.gni

 # Copyright 2015 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/arm.gni")
 import("//build/config/chrome_build.gni")
 import("//build/config/chromecast_build.gni")
 import("//build/config/compiler/pgo/pgo.gni")
 import("//build/config/sanitizers/sanitizers.gni")
@@ skipping 48 matching lines @@
   # Note that doing a link repro uses a lot of disk space and slows down the
   # build, so this shouldn't be enabled on too many targets.
   #
   # See crbug.com/669854.
   linkrepro_root_dir = ""
 
   # Whether or not we should use position independent code.
   use_pic = true
 }
 
-# Determine the default setting for enable_frame_pointers, based on the platform
+# Determine whether to enable or disable frame pointers, based on the platform
 # and build arguments.
 if (is_mac || is_ios) {
-  _default_enable_frame_pointers = true
+  enable_frame_pointers = true
 } else if (is_win) {
   # 64-bit Windows ABI doesn't support frame pointers.
   if (target_cpu == "x64") {
-    _default_enable_frame_pointers = false
+    enable_frame_pointers = false
   } else {
-    _default_enable_frame_pointers = true
+    enable_frame_pointers = true
   }
+} else if (is_chromeos) {
+  # ChromeOS requires frame pointers in x64 builds, to support CWP.
+  # TODO(711784): Building ARM Thumb without frame pointers can lead to code
+  # in ChromeOS which triggers some ARM A12/A17 errata. They can be disabled
+  # on non-x64 once that is resolved.
+  enable_frame_pointers = true
 } else if (current_cpu == "arm64") {
   # Ensure that stacks from arm64 crash dumps are usable (crbug.com/391706).
-  _default_enable_frame_pointers = true
-} else if (is_chromeos && current_cpu == "arm" && arm_use_thumb) {
-  # TODO(711784): Building ARM Thumb without frame pointers can lead to code
-  # in ChromeOS which triggers some ARM A12/A17 errata.
-  _default_enable_frame_pointers = true
+  enable_frame_pointers = true
 } else {
   # Explicitly ask for frame pointers, otherwise:
   # * Stacks may be missing for sanitizer and profiling builds.
   # * Debug tcmalloc can crash (crbug.com/636489).
-  _default_enable_frame_pointers =
-      using_sanitizer || enable_profiling || is_debug
-}
-
-declare_args() {
-  # True if frame pointers should be generated, false otherwise.
-  enable_frame_pointers = _default_enable_frame_pointers
+  enable_frame_pointers = using_sanitizer || enable_profiling || is_debug
 }
 
 # In general assume that if we have frame pointers then we can use them to
 # unwind the stack. However, this requires that they are enabled by default for
 # most translation units, that they are emitted correctly, and that the
 # compiler or platform provides a way to access them.
 can_unwind_with_frame_pointers = enable_frame_pointers
 if (current_cpu == "arm" && arm_use_thumb) {
   # We cannot currently unwind ARM Thumb frame pointers correctly.
   can_unwind_with_frame_pointers = false
@@ skipping 67 matching lines @@
 }
 
 # Assert that the configuration isn't going to hit https://crbug.com/648948.
 assert(ignore_elf32_limitations || !is_android ||
            (android_64bit_target_cpu && !build_apk_secondary_abi) ||
            is_component_build || symbol_level < 2,
        "Android 32-bit non-component builds cannot have symbol_level=2 " +
            "due to 4GiB file size limit, see https://crbug.com/648948. " +
            "If you really want to try this out, " +
            "set ignore_elf32_limitations=true.")