Build error in release mode (Android/Armv4/GCC4.9/Qt5.7.0) but not in debug...

KroMignon

Hi dear GCC/Qt/Android experts.

I need some help on a very strange problem which I don't understand.

I have create an Android application base on Qt 5.7.0. This application uses some libraries I'm already using for other projects based on Qt 5.4 (Windows XP/7 and Linux x86/ARM4).

But one of those libraries won't build as "Release" on Android but build in "Debug"!

My build configuration is following:

Build machine is using Windows 7 Pro/64 bit
Qt Creator 4.1.0
Android NDK r12 (I've also tested r13b and r14Beta1) 32 bit
Android SDK Tools 25.2.4
Qt 5.7.0 for Android armv7

The error I've got is as following:

C:\Android\android-ndk-r14-beta1/toolchains/arm-linux-androideabi-4.9/prebuilt/windows/bin/arm-linux-androideabi-g++ -c -Wno-psabi -march=armv7-a -mfloat-abi=softfp -mfpu=vfp -ffunction-sections -funwind-tables -fstack-protector -fno-short-enums -DANDROID -Wa,--noexecstack -fno-builtin-memmove -std=c++11 -O2 -Os -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 -mthumb -Wall -Wno-psabi -W -D_REENTRANT -fPIC -DAPP_VERSION=\"3.09.101.00000\" -DGCCOMLIB_LIBRARY -DQT_NO_DEBUG -DQT_NETWORK_LIB -DQT_SQL_LIB -DQT_CORE_LIB -I..\..\..\..\GCComLib\trunk\GCComLib -I. -I..\..\..\..\GCComLib\trunk -I..\..\..\..\StdLib\trunk\StdLib -IC:\Qt\5.7\android_armv7\include -IC:\Qt\5.7\android_armv7\include\QtNetwork -IC:\Qt\5.7\android_armv7\include\QtSql -IC:\Qt\5.7\android_armv7\include\QtCore -I. -isystem C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\include -isystem C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\libs\armeabi-v7a\include -isystem C:\Android\android-ndk-r14-beta1\platforms\android-9\arch-arm\usr\include -IC:\Qt\5.7\android_armv7\mkspecs\android-g++ -o GCDatagram.obj ..\..\..\..\GCComLib\trunk\GCComLib\UDP\GCDatagram.cpp
In file included from C:\Qt\5.7\android_armv7\include/QtCore/QtCore:13:0,
                 from C:\Qt\5.7\android_armv7\include/QtSql/QtSqlDepends:3,
                 from C:\Qt\5.7\android_armv7\include/QtSql/QtSql:3,
                 from ..\..\..\..\StdLib\trunk\StdLib/DataType/GCDataType.h:6,
                 from ..\..\..\..\GCComLib\trunk\GCComLib/Messages/MessageBase.h:8,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\UDP\GCDatagram.h:6,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\UDP\GCDatagram.cpp:1:
C:\Qt\5.7\android_armv7\include/QtCore/qendian.h:53:0: warning: "QT_HAS_BUILTIN" redefined
 #  define QT_HAS_BUILTIN(x)     __has_builtin(x)
 ^
In file included from C:\Qt\5.7\android_armv7\include/QtCore/qglobal.h:83:0,
                 from ..\..\..\..\GCComLib\trunk\GCComLib/GCComLibGlobal.h:4,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\UDP\GCDatagram.h:4,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\UDP\GCDatagram.cpp:1:
C:\Qt\5.7\android_armv7\include/QtCore/qcompilerdetection.h:1209:0: note: this is the location of the previous definition
 #  define QT_HAS_BUILTIN(x)             0
 ^
C:\Android\android-ndk-r14-beta1/toolchains/arm-linux-androideabi-4.9/prebuilt/windows/bin/arm-linux-androideabi-g++ -c -Wno-psabi -march=armv7-a -mfloat-abi=softfp -mfpu=vfp -ffunction-sections -funwind-tables -fstack-protector -fno-short-enums -DANDROID -Wa,--noexecstack -fno-builtin-memmove -std=c++11 -O2 -Os -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 -mthumb -Wall -Wno-psabi -W -D_REENTRANT -fPIC -DAPP_VERSION=\"3.09.101.00000\" -DGCCOMLIB_LIBRARY -DQT_NO_DEBUG -DQT_NETWORK_LIB -DQT_SQL_LIB -DQT_CORE_LIB -I..\..\..\..\GCComLib\trunk\GCComLib -I. -I..\..\..\..\GCComLib\trunk -I..\..\..\..\StdLib\trunk\StdLib -IC:\Qt\5.7\android_armv7\include -IC:\Qt\5.7\android_armv7\include\QtNetwork -IC:\Qt\5.7\android_armv7\include\QtSql -IC:\Qt\5.7\android_armv7\include\QtCore -I. -isystem C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\include -isystem C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\libs\armeabi-v7a\include -isystem C:\Android\android-ndk-r14-beta1\platforms\android-9\arch-arm\usr\include -IC:\Qt\5.7\android_armv7\mkspecs\android-g++ -o GCComHandler.obj ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.cpp
In file included from C:\Qt\5.7\android_armv7\include/QtCore/QtCore:13:0,
                 from C:\Qt\5.7\android_armv7\include/QtSql/QtSqlDepends:3,
                 from C:\Qt\5.7\android_armv7\include/QtSql/QtSql:3,
                 from ..\..\..\..\StdLib\trunk\StdLib/DataType/GCDataType.h:6,
                 from ..\..\..\..\GCComLib\trunk\GCComLib/Messages/MessageBase.h:8,
                 from ..\..\..\..\GCComLib\trunk\GCComLib/UDP/GCDatagram.h:6,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCUdpSocket.h:11,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.h:14,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.cpp:1:
C:\Qt\5.7\android_armv7\include/QtCore/qendian.h:53:0: warning: "QT_HAS_BUILTIN" redefined
 #  define QT_HAS_BUILTIN(x)     __has_builtin(x)
 ^
In file included from C:\Qt\5.7\android_armv7\include/QtCore/qglobal.h:83:0,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qiodevice.h:43,
                 from C:\Qt\5.7\android_armv7\include/QtNetwork/qabstractsocket.h:43,
                 from C:\Qt\5.7\android_armv7\include\QtNetwork/qudpsocket.h:43,
                 from C:\Qt\5.7\android_armv7\include\QtNetwork/QUdpSocket:1,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.h:4,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.cpp:1:
C:\Qt\5.7\android_armv7\include/QtCore/qcompilerdetection.h:1209:0: note: this is the location of the previous definition
 #  define QT_HAS_BUILTIN(x)             0
 ^
In file included from C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\include/atomic:41:0,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qatomic_cxx11.h:45,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qbasicatomic.h:53,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qatomic.h:46,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qglobal.h:1145,
                 from C:\Qt\5.7\android_armv7\include/QtCore/qiodevice.h:43,
                 from C:\Qt\5.7\android_armv7\include/QtNetwork/qabstractsocket.h:43,
                 from C:\Qt\5.7\android_armv7\include\QtNetwork/qudpsocket.h:43,
                 from C:\Qt\5.7\android_armv7\include\QtNetwork/QUdpSocket:1,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.h:4,
                 from ..\..\..\..\GCComLib\trunk\GCComLib\Client\GCComHandler.cpp:1:
C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\include/bits/atomic_base.h: In member function 'void Geocept::GCComLib::Client::GCComHandler::processIncomingMsg(Geocept::GCComLib::Messages::MessageBasePtr)':
C:\Android\android-ndk-r14-beta1\sources\cxx-stl\gnu-libstdc++\4.9\include/bits/atomic_base.h:584:70: error: failure memory model cannot be stronger than success memory model for '__atomic_compare_exchange'
  return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);

Additionnal information
==> MessageBasePtr is as typedef of QSharedPointer<MessageBase>
MessageBase is a virtual class used as base class for message handling.

I don't understand what this does mean failure memory model cannot be stronger than success memory model for '__atomic_compare_exchange'

And why this build fine in Debug mode?!?

raven-worx

@KroMignon
it seems this is only an issue with gcc 4.x version's optimization.
It should work with gcc 5.x
Especially with the -Os flag in release mode.

See this.

KroMignon

@raven-worx : thanks for your quick answer, but GCC comes with Android SDK... so I don't have any chance to change GCC version.

How can I remove this -Os flag in my project file (PRO format)?

KroMignon

@raven-worx : Thanks a lot for pointing out the problem.

In fact, it was the -Os optimization from GCC 4.9, I've turn it off for Android in my PRO file with following command:

android: QMAKE_CXXFLAGS_RELEASE -= -Os

Now I can build my library in release mode :)
Perhaps this could help someone else.

Have a nice day.

raven-worx

@KroMignon
you can try the following:

QMAKE_CXXFLAGS_RELEASE -= -Os
QMAKE_CFLAGS_RELEASE_WITH_DEBUGINFO -= -Os

Maybe add an other optimization flag as desired.