Android Ndk Std::To_String Support

Android ndk std::to_string support

You can try LOCAL_CFLAGS := -std=c++11, but note that not all C++11 APIs are available with the NDK's gnustl. Full C++14 support is available with libc++ (APP_STL := c++_shared).

The alternative is to implement it yourself.

#include <string>
#include <sstream>

template <typename T>
std::string to_string(T value)
{
    std::ostringstream os ;
    os << value ;
    return os.str() ;
}

int main()
{
    std::string perfect = to_string(5) ;
}

Error: no member named 'to_string' in namespace 'std'; did you mean 'toString'? Gradle+Cmake

Does it mean CLang does not meet STandarD?

No, it is because minimal std library set in Android NDK by default.

I use gradle build system:

android {
  ...
  defaultConfig {
    ...
    // This block is different from the one you use to link Gradle
    // to your CMake build script.
    externalNativeBuild {
      cmake {
        ...
        // Use the following syntax when passing arguments to variables:
        // arguments "-DVAR_NAME=VALUE"
        // ------------------- ANSWER -------------------
        arguments "-DANDROID_STL=c++_shared"
      }
    }
  }
  buildTypes {...}

  // Use this block to link Gradle to your CMake build script.
  externalNativeBuild {
    cmake {...}
  }
}

Read these:

https://developer.android.com/ndk/guides/cmake.html#variables

https://developer.android.com/ndk/guides/cpp-support.htm

Android NDK Source Compiled & Build Successfully - But Function 'to_string' could not be resolved in Eclipse IDE

After referring the answer by @Khaled Lakehal, I myself posting this answer for my question.Hope this may help someone.

Followed the below step to make it work:

1. Update the eclipse version from Luna to latest Mars 2
2. Imported the existing project from the old version of the eclipse
   using -> import -> Existing Android code into Workspace
3. Had some problem with the C/C++ project conversion after import. So followed this link to undo the C/C++ project conversion
4. Converted the project to C/C++ newly.
5. To remove the error, I referred this link, and selected the "Run with build" only
6. Close & Reopen the IDE

So now able to use the std::to_string & std::stoll functions.

android NDK complains std::nearbyint is not a member of std

This is part of https://github.com/android-ndk/ndk/issues/82. GNU's libstdc++ is overly broad with their feature guards. We're working on stabilizing the NDK's solution for libc++ so we can just move entirely over to that instead.

Does NDK support C++14?

Bionic is the standard C library. It does not support any C++ std library features let alone C++14.

If you are asking about NDK, then as per the cpp-support page for NDK, LLVM's libc++ is the C++ standard library that has been used by the Android OS since Lollipop and this supports C++17 features.

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