Motown: ffmpeg implementations of framework 'parts'

build/config/compiler/BUILD.gn

 # 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/chrome_build.gni")
 if (current_cpu == "arm") {
   import("//build/config/arm.gni")
 }
 if (current_cpu == "mipsel" || current_cpu == "mips64el") {
@@ skipping 831 matching lines @@
   # always have different versions. Certain flags may not be recognized by
   # one version or the other.
   if (!is_nacl) {
     # Flags NaCl (Clang 3.7) does not recognize.
     default_warning_flags += [
       # TODO(smklein): Enable this, crbug.com/507717
       "-Wno-shift-negative-value",
 
       # TODO(smklein): Consider enabling this once not broken by third party
       "-Wno-bitfield-width",
+
+      # TODO(dalesat): Remove once not broken by third party (ffmpeg).
+      "-Wno-constant-conversion",

[johngro, 2016/03/01 01:31:38]

Is it possible to stuff this in the build rules for just ffmpeg instead of
globally?

If not, you probably want to run this by jamesr@; disabling a warning like this
globally seems like a pretty big deal.  If we end up doing this, we definitely
need to log a bug (like has been done by some people above).

[jamesr, 2016/03/01 17:56:43]

Don't disable warnings like this globally.  You can add this to the cflags for
the ffmpeg target (or targets) that trigger the warning.

[dalesat, 2016/03/01 20:43:01]

FWIW, I'm restoring a flag that was only recently removed. I've made several
attempts to do this more locally to no avail. We may need our own branch of
ffmpeg to achieve this.

     ]
   }
 }
 
 # chromium_code ---------------------------------------------------------------
 #
 # Toggles between higher and lower warnings for code that is (or isn't)
 # part of Chromium.
 
 config("chromium_code") {
@@ skipping 255 matching lines @@
   if (symbol_level == 0) {
     configs = [ ":no_symbols" ]
   } else if (symbol_level == 1) {
     configs = [ ":minimal_symbols" ]
   } else if (symbol_level == 2) {
     configs = [ ":symbols" ]
   } else {
     assert(false)
   }
 }