c++/8/memory:116:25: error: cast from pointer to smaller type 'uintptr_t' (aka 'unsigned int') loses information

[svonidze]

I have some code written in C++ and used in the Flutter project, I cannot run nor build code on Linix Mint, works ok on Mac and Windows.

Getting this error on Linix Mint

  In file included from ../../../../src/main/opencv2/include/opencv2/core/cvstd_wrapper.hpp:11:
  /snap/flutter/current/usr/include/c++/8/memory:116:25: error: cast from pointer to smaller type 'uintptr_t' (aka 'unsigned int') loses information
    const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

while trying to run/build the project.
.../c++/8/memory:116:25 leads to the code

/**
 *  @brief Fit aligned storage in buffer.
 *
 *  [ptr.align]
 *
 *  This function tries to fit @a __size bytes of storage with alignment ...
 */
inline void*
align(size_t __align, size_t __size, void*& __ptr, size_t& __space) noexcept
{
  const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);   // <--- fails here
  const auto __aligned = (__intptr - 1u + __align) & -__align;
  const auto __diff = __aligned - __intptr;
  if ((__size + __diff) > __space)
    return nullptr;
  else
    {
      __space -= __diff;
      return __ptr = reinterpret_cast<void*>(__aligned);
    }
}

Full error log

Execution failed for task ':project_name_ffi:buildCMakeRelWithDebInfo[arm64-v8a]'.
> Build command failed.
  Error while executing process /home/sergey/Android/Sdk/cmake/3.18.1/bin/ninja with arguments {-C /home/sergey/projects/company_name/project_name/packages/project_name_ffi/android/.cxx/RelWithDebInfo/1v1k334p/arm64-v8a native-lib}
  ninja: Entering directory `/home/sergey/projects/company_name/project_name/packages/project_name_ffi/android/.cxx/RelWithDebInfo/1v1k334p/arm64-v8a'
  [1/4] Building CXX object CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/general/general_funtion.cpp.o
  clang++: warning: -lGLESv2: 'linker' input unused [-Wunused-command-line-argument]
  clang++: warning: -Wl,--no-whole-archive: 'linker' input unused [-Wunused-command-line-argument]
  [2/4] Building CXX object CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp.o
  FAILED: CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp.o 
  /home/sergey/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++ --target=aarch64-none-linux-android23 --gcc-toolchain=/home/sergey/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64 --sysroot=/home/sergey/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64/sysroot -Dnative_lib_EXPORTS -I../../../../../cpp/general -I../../../../src/main/opencv2/include -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security  -lGLESv2 -frtti -fexceptions -std=c++11 -Wl,--no-whole-archive -O2 -g -DNDEBUG -fPIC -MD -MT CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp.o -MF CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp.o.d -o CMakeFiles/native-lib.dir/home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp.o -c /home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp
  clang++: warning: -lGLESv2: 'linker' input unused [-Wunused-command-line-argument]
  clang++: warning: -Wl,--no-whole-archive: 'linker' input unused [-Wunused-command-line-argument]
  In file included from /home/sergey/projects/company_name/project_name/packages/project_name_ffi/cpp/native_project_name.cpp:2:
  In file included from ../../../../src/main/opencv2/include/opencv2/opencv.hpp:52:
  In file included from ../../../../src/main/opencv2/include/opencv2/core.hpp:53:
  In file included from ../../../../src/main/opencv2/include/opencv2/core/base.hpp:58:
  In file included from ../../../../src/main/opencv2/include/opencv2/core/cvstd.hpp:81:
  In file included from ../../../../src/main/opencv2/include/opencv2/core/cvstd_wrapper.hpp:11:
  /snap/flutter/current/usr/include/c++/8/memory:116:25: error: cast from pointer to smaller type 'uintptr_t' (aka 'unsigned int') loses information
    const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

flutter doctor -v returns

[✓] Flutter (Channel stable, 3.0.2, on Linux Mint 20.3 5.4.0-117-generic, locale en_US.UTF-8)
    • Flutter version 3.0.2 at /home/sergey/snap/flutter/common/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision cd41fdd495 (8 days ago), 2022-06-08 09:52:13 -0700
    • Engine revision f15f824b57
    • Dart version 2.17.3
    • DevTools version 2.12.2

[✓] Android toolchain - develop for Android devices (Android SDK version 32.1.0-rc1)
    • Android SDK at /home/sergey/Android/Sdk
    • Platform android-32, build-tools 32.1.0-rc1
    • Java binary at:
      /home/sergey/.local/share/JetBrains/Toolbox/apps/AndroidStudio/ch-0/213.7172.25.2113.8684940/jre/bin/java
    • Java version OpenJDK Runtime Environment (build 11.0.13+0-b1751.21-8125866)
    • All Android licenses accepted.

[✓] Chrome - develop for the web
    • Chrome at google-chrome

[✓] Linux toolchain - develop for Linux desktop
    • clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
    • cmake version 3.10.2
    • ninja version 1.8.2
    • pkg-config version 0.29.1

[✓] Android Studio (version 2021.3)
    • Android Studio at /home/sergey/.local/share/JetBrains/Toolbox/apps/AndroidStudio/ch-0/213.7172.25.2113.8684940
    • Flutter plugin version 68.1.3
    • Dart plugin version 213.7371
    • Java version OpenJDK Runtime Environment (build 11.0.13+0-b1751.21-8125866)

[✓] VS Code
    • VS Code at /snap/code/current
    • Flutter extension can be installed from:
      🔨 https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter

[✓] Connected device (2 available)
    • Linux (desktop) • linux  • linux-x64      • Linux Mint 20.3 5.4.0-117-generic
    • Chrome (web)    • chrome • web-javascript • Google Chrome 102.0.5005.115

[✓] HTTP Host Availability
    • All required HTTP hosts are available

[maheshj01]

Hi @svonidze, Looking at those error logs, Those issues seem to be coming from c++ code (from your code or elsewhere) But not from flutter.

error: cast from pointer to smaller type 'uintptr_t' (aka 'unsigned int') loses information
const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);

Also this seems to be a common cast error in c++, Please see if this helps resolve the issue https://stackoverflow.com/questions/22419063/error-cast-from-pointer-to-smaller-type-int-loses-information-in-eaglview-mm

Closing as this is not related to flutter.

[svonidze]

hey @maheshmnj
I read many treads on the Internet re this error and this stack overflow link as well, there people recommend to change code to fix the problem however the code is from

/flutter/current/usr/include/c++/8/

which is (I guess) a flutter part.

I cant explain why C++ 8 (version) is used there, maybe I need somehow to force using a latest version of C++ (11?). Do you know the way?

[svonidze]

I addressed this issue by reinstalling flutter, it was installed with snap and did fail with the error above, I purged this
sudo snap remove flutter and install flutter with git clone.

all credits to the guy https://stackoverflow.com/questions/70149507/flutter-build-failed-for-android-bitmapexternalnativebuilddebug.

Anyway something wrong with flutter in snap!

[maheshj01]

Thanks for the update @svonidze Please consider reporting this issue at https://github.com/canonical/flutter-snap

[github-actions]

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