Adding std::tuple to std::map compiles and works on Macos, not on Linux

Question

Here is the following code (assuming id and speed are already initialised, and includes are correct):

std::map<int, std::tuple<double, double>> mymap;

mymap.insert(std::pair<int, std::tuple<double, double>>(id, speed));

This code compiles and works under Macos (Xcode using clang-800.0.42.1) and Linux (Ubuntu 16.04, gcc 5.4.0).

mymap.insert(std::tie(id, speed));

This code compiles and works under Macos (Xcode using clang-800.0.42.1), but not under Linux (Ubuntu 16.04, gcc 5.4.0). For the latter, the error raised is:

error: no matching function for call to 'std::map<int, std::tuple<double, double> >::insert(std::tuple<int&, std::tuple<double, double>&>)

Note that the problem is similar when trying to insert an std::tuple to an std::map (bypassed by using std::pair instead of std::tuple).

Can anyone explain? Thanks!

Answer 1

Tuples are added to C++ form C++11.

std::tuple

For use of C++11 features you need to add -std=c++11 flag to your gcc compiler by default it is not activated yet.

I think mac compiles because you are using Xcode and maybe the -std=c++11 flag is already set from IDA.