Re-enable WebRtcIsacfix_AllpassFilter2FixDec16Neon

webrtc/modules/audio_coding/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/arm.gni")
 import("//third_party/protobuf/proto_library.gni")
@@ skipping 593 matching lines @@
       ]
       sources -= [ "codecs/isac/fix/source/pitch_filter_c.c" ]
     }
   }
 }
 
 if (rtc_build_with_neon) {
   source_set("isac_neon") {
     sources = [
       "codecs/isac/fix/source/entropy_coding_neon.c",
+      "codecs/isac/fix/source/filterbanks_neon.c",
       "codecs/isac/fix/source/filters_neon.c",
       "codecs/isac/fix/source/lattice_neon.c",
       "codecs/isac/fix/source/transform_neon.c",
     ]
-    if (current_cpu != "arm64" || !is_clang) {
-      # Disable AllpassFilter2FixDec16Neon function due to a clang bug.
-      # For more details refer to:
-      # https://code.google.com/p/webrtc/issues/detail?id=4567
-      sources += [ "codecs/isac/fix/source/filterbanks_neon.c" ]
-    }
 
     if (current_cpu != "arm64") {
       # Enable compilation for the NEON instruction set. This is needed
       # since //build/config/arm.gni only enables NEON for iOS, not Android.
       # This provides the same functionality as webrtc/build/arm_neon.gypi.
       configs -= [ "//build/config/compiler:compiler_arm_fpu" ]
       cflags = [ "-mfpu=neon" ]
     }
 
     # Disable LTO on NEON targets due to compiler bug.
@@ skipping 168 matching lines @@
     "../../system_wrappers",
   ]
 
   defines = []
 
   if (rtc_include_opus) {
     defines += [ "WEBRTC_CODEC_OPUS" ]
     deps += [ ":webrtc_opus" ]
   }
 }