bug report - std::sto* in g++

[jaiselrahman]

First of all, Thank you for this great app
It is helps me greatly for learning programmings

I found that when compiling this c++ code using g++

    #include<iostream>
    #include<string>
    using namespace std;
    int main()                                     
    {                    
        string s="566";                       
        int i;
        i=stol(s); 
        cout<<i;                             
        cout<<'\n'<<stod("937");
        cout<<'\n'<<to_string(239.399);
        return 0;
  } 

the compiler throws error

stoi.cpp: In function 'int main()':
stoi.cpp:10:11: error: 'stol' was not declared in this scope
i=stol(s);
^
stoi.cpp:12:25: error: 'stod' was not declared in this scope
cout<<'\n'<<stod("937");
^
stoi.cpp:13:32: error: 'to_string' was not declared in this scope
cout<<'\n'<<to_string(239.399);
^

my compiler version is 6.1.0

[fornwall]

This is a bug in the Android NDK (which Termux is based on): android/ndk#82

It is scheduled to be resolved in the next release (r13) of the NDK, at which time the fix will propagate to Termux as a package update!

[jaiselrahman]

thanks

i found that adding these to above headers fixes the problem (temporarily)

    #define _GLIBCXX_HAVE_WCSTOF 1
    #define _GLIBCXX_USE_C99 1

Again thanks for this awesome app

[fornwall]

Unfortunately the progress on the NDK side has been slower than expected. However, according to the NDK roadmap, the next release (r15) states:

With this project finished, libc++ will be safe to use

If it works ok, the plan is to switch to libc++ in Termux when r15 of the NDK is available. This will bring us a modern C++ library fixing these and other issues.

The NDK release schedule currently has r15 marked for release during Late May/Early June 2017.

[Exaeta]

@fornwall Can we get the beta version? This is stopping me from compiling software I want to try to use on android...

[fornwall]

Termux has just switched to libc++, so after updating packages things such as std::to_string, std::stod and friends should start working!

Note that C++ programs and libraries should be rebuilt completely, as Termux now links against libc++ by default, and you don't want to mix STL implementations in the same program.