AFAIK there should not be any differences.

Hmm, which target did you build specifically? 

Our config("common_config") should add on -WExtra for non-android posix platforms such as mac. I wonder if the particular target you built don't inherit from that config?

Provisional cl: https://codereview.webrtc.org/2128813002

This was from building the chrome target. It's possible that the building-within-chrome and the standalone build have different flags.

Ok!

My CL for fixing the "new" flags worked except for Android. I don't know why it happens though because my patch _removes_ the warning.

FAILED: obj/webrtc/api/libjingle_peerconnection_jni/peerconnection_jni.o 
/b/build/slave/cache/cipd/goma/gomacc ../../third_party/android_tools/ndk/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-g++ -MMD -MF obj/webrtc/api/libjingle_peerconnection_jni/peerconnection_jni.o.d -DV8_DEPRECATION_WARNINGS -DENABLE_NOTIFICATIONS -DENABLE_BROWSER_CDMS -DENABLE_PRINTING=1 -DENABLE_BASIC_PRINTING=1 -DENABLE_SPELLCHECK=1 -DUSE_BROWSER_SPELLCHECKER=1 -DUSE_OPENSSL_CERTS=1 -DNO_TCMALLOC -DUSE_EXTERNAL_POPUP_MENU=1 -DENABLE_WEBRTC=1 -DDISABLE_NACL -DENABLE_SUPERVISED_USERS=1 -DVIDEO_HOLE=1 -DSAFE_BROWSING_DB_REMOTE -DCHROMIUM_BUILD -DENABLE_MEDIA_ROUTER=1 -DENABLE_WEBVR -DFIELDTRIAL_TESTING_ENABLED -D_FILE_OFFSET_BITS=64 -DANDROID -DHAVE_SYS_UIO_H -DANDROID_NDK_VERSION=r10e -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FORTIFY_SOURCE=2 -D__GNU_SOURCE=1 -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DWEBRTC_RESTRICT_LOGGING -DWEBRTC_INCLUDE_INTERNAL_AUDIO_DEVICE -DEXPAT_RELATIVE_PATH -DWEBRTC_BUILD_LIBEVENT -DWEBRTC_ARCH_ARM -DWEBRTC_ARCH_ARM_V7 -DWEBRTC_HAS_NEON -DWEBRTC_POSIX -DWEBRTC_LINUX -DWEBRTC_ANDROID -I../.. -Igen -I../../third_party/libyuv -I../../third_party/libyuv/include -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -funwind-tables -fPIC -pipe -ffunction-sections -fno-short-enums -finline-limit=64 -march=armv7-a -mfloat-abi=softfp -mthumb -mthumb-interwork -mtune=generic-armv7-a -fno-tree-sra -fno-caller-saves -mfpu=neon -Wall -Werror -Wno-psabi -Wno-unused-local-typedefs -Wno-maybe-uninitialized -Wno-missing-field-initializers -Wno-unused-parameter -Os -fomit-frame-pointer -fno-ident -fdata-sections -ffunction-sections -g2 --sysroot=../../third_party/android_tools/ndk/platforms/android-16/arch-arm -fvisibility=hidden -Wextra -Wno-unused-parameter -Wno-missing-field-initializers -Wno-strict-overflow -fno-builtin-cos -fno-builtin-sin -fno-builtin-cosf -fno-builtin-sinf -Wno-sign-compare -fno-threadsafe-statics -fvisibility-inlines-hidden -std=gnu++11 -Wno-narrowing -fno-rtti -isystem../../third_party/android_tools/ndk/sources/cxx-stl/llvm-libc++/libcxx/include -isystem../../third_party/android_tools/ndk/sources/cxx-stl/llvm-libc++abi/libcxxabi/include -isystem../../third_party/android_tools/ndk/sources/android/support/include -fno-exceptions -Wnon-virtual-dtor -Woverloaded-virtual -c ../../webrtc/api/android/jni/peerconnection_jni.cc -o obj/webrtc/api/libjingle_peerconnection_jni/peerconnection_jni.o
../../webrtc/api/android/jni/peerconnection_jni.cc: In function 'void webrtc_jni::Java_org_webrtc_Logging_nativeEnableTracing(JNIEnv*, jclass, jstring, jint)':
../../webrtc/api/android/jni/peerconnection_jni.cc:897:34: error: unused variable 'g_trace_callback' [-Werror=unused-variable]
       static LogcatTraceContext* g_trace_callback = new LogcatTraceContext();
                                  ^
cc1plus: all warnings being treated as errors

Oh, wait, adding the flag turns off the warning. Ok, got it.

Maybe you can fix the warning on android? What's the status here?

Reassigning to Edward since Patrik is now on vacation. This should be addressed as part of our GN migration which will happen in August (tracked in https://bugs.webrtc.org/5949).

rsesek: may I ask what tool or collection of commands you're using when doing this comparison? I've considered adding something to the bots but I leaning towards doing a one-time audit instead since the cost of implementing something automated seemed pretty high.

I used the gyp_flag_comparison script like so:

% PYTHONPATH=tools/gn/bin python
Python 2.7.10 (default, Oct 23 2015, 19:19:21) 
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import gyp_flag_compare as fc
>>> import sys
>>> import pprint
>>> sys.displayhook = pprint.pprint
>>> fc.ConfigureBuild(
...           ['disable_nacl=1', 'buildtype=Official', 'branding=Chrome'],
...           ['enable_nacl=false', 'is_official_build=true',
...            'is_chrome_branded=true'])
Regenerating in out/gn_flags...
gn gen out/gn_flags --args="is_debug=false is_component_build=false enable_nacl=false is_official_build=true is_chrome_branded=true"
Regenerating in out_gyp_flags/Release...
python build/gyp_chromium -Goutput_dir=out_gyp_flags -Gconfig=Release -Ddisable_nacl=1 -Dbuildtype=Official -Dbranding=Chrome
None
>>> chrome = fc.Comparison('chrome')
ninja -C out/gn_flags -t commands chrome
ninja -C out_gyp_flags/Release -t commands chrome
>>> fc.Counts(chrome.missing_in_gyp['other'])
{'-Xclang -add-plugin': 430,
 '-Xclang -load': 430,
 '-Xclang -plugin-arg-find-bad-constructs': 430,
 '-Xclang /Volumes/Build/src/third_party/llvm-build/Release+Asserts/lib/libBlinkGCPlugin.dylib': 3052,
 '-Xclang /Volumes/Build/src/third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.dylib': 430,
 '-Xclang check-implicit-copy-ctors': 430,
 '-Xclang check-templates': 430,
 '-Xclang find-bad-constructs': 430,
 '-Xclang follow-macro-expansion': 430,
 '-include': 14,
 '-mavx2': 1,
 '-msse2': 1,
 '-w': 23,
 'obj/sdch/sdch.logging_forward.h-cc': 12,
 'obj/third_party/WebKit/Source/build/mac/blink_platform.Prefix.h-cc': 536,
 'obj/third_party/WebKit/Source/build/mac/blink_platform.Prefix.h-mm': 18,
 'obj/third_party/WebKit/Source/build/mac/webcore_dom.Prefix.h-cc': 242,
 'obj/third_party/WebKit/Source/build/mac/webcore_generated.Prefix.h-cc': 99,
 'obj/third_party/WebKit/Source/build/mac/webcore_html.Prefix.h-cc': 247,
 'obj/third_party/WebKit/Source/build/mac/webcore_remaining.Prefix.h-cc': 743,
 'obj/third_party/WebKit/Source/build/mac/webcore_remaining.Prefix.h-mm': 1,
 'obj/third_party/WebKit/Source/build/mac/webcore_rendering.Prefix.h-cc': 167,
 'obj/third_party/WebKit/Source/build/mac/webcore_rendering.Prefix.h-mm': 1,
 'obj/third_party/WebKit/Source/build/mac/webcore_svg.Prefix.h-cc': 198}
>>> chrome.missing_in_gyp['other']['-msse2']
['/Volumes/Build/src/third_party/webrtc/modules/desktop_capture/differ_block_sse2.cc']
>>> fc.CountsByDirname(chrome.missing_in_gn['warnings']['-Wno-unused-variable'])
{'/Volumes/Build/src/third_party/sfntly/src/cpp/src/sample/chromium': 2,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly': 3,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/data': 8,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/port': 4,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/table': 7,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/table/bitmap': 17,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/table/core': 8,
 '/Volumes/Build/src/third_party/sfntly/src/cpp/src/sfntly/table/truetype': 2,
 '/Volumes/Build/src/third_party/webrtc/base': 72,
 '/Volumes/Build/src/third_party/webrtc/pc': 10}

Edward, can you provide an update on this since we've been starting to audit these kind of things. If it's still valid, we should try to identify what's going on with this -msse2 flag

The thing with the mmse2 flag was addressed in
https://codereview.webrtc.org/2247293002/

I wonder why it didn't post a message here.

Re #12: I filed  bug 642755  to ask figure out what's up with bugdroid.

Could you run a similar run as rsesek@ did above in Chromium, to see if we can mark this bug as fixed?

ping?

Edward, can we close this or do we need to repeat the run I requested in #13 to ensure we don't differ?

I don't think we can run this anymore.
I'm fairly sure we can close this now.

Ok.

[bulk-edit : please ignore if not applicable]

Could you please set the correct milestone for this issue?