Calling threaded functions with arguments not possible

Question

I know this question appear similar to already answered ones, but since the answer given to them does not work for me, i do not regard this question to be a dublicate of them

I am well aware that the question: how do i call a c++ function as a thread which has 1 or more arguments has been answered several times -- both here, and on various tutorials -- and in every case the answer is simply that this is the way to do it:

(example taken directly from this question)

#include <string>
#include <iostream>
#include <thread>

using namespace std;

// The function we want to execute on the new thread.
void task1(string msg)
{
    cout << "task1 says: " << msg;
}

int main()
{
    // Constructs the new thread and runs it. Does not block execution.
    thread t1(task1, "Hello");

    // Makes the main thread wait for the new thread to finish execution, therefore blocks its own execution.
    t1.join();
}

However i have tried copypasting both this code and many more (more or less identical) examples of how to do this, and yet, every time i compile (through termial as such g++ test.cpp -o test.app (the .app must be added because i am on a Mac (note that this way of compiling does in fact work for me, and that the error is simply not a result of me not knowing how to compile a c++ program))) such a program i get this error message:

test.cpp:16:12: error: no matching constructor for initialization of 'std::__1::thread'
    thread t1(task1, "Hello");
           ^  ~~~~~~~~~~~~~~
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:389:9: note: candidate constructor template not viable: requires single argument '__f', but
      2 arguments were provided
thread::thread(_Fp __f)
        ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:297:5: note: candidate constructor not viable: requires 1 argument, but 2 were provided
    thread(const thread&);
    ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/thread:304:5: note: candidate constructor not viable: requires 0 arguments, but 2 were provided
    thread() _NOEXCEPT : __t_(0) {}

My question therefor is, what am i doing wrong compared to all the people who possitively can make threaded functions with arguments, and since i have not found any questions asked by people experiancing similar problems, I do not regard this question a duplicate of the many How do i call a threaded function with arguments

As far as i know, using threads doesn't require any specific compiler flags, and since i perfectly fine can run programs with threaded functions without arguments, you can not claim that my computer or compiler is incabable of using threads altogether.

If you do `g++ --version` what does it report? Do you have a very old version of Clang (on macOS `gcc` and `g++` are usually aliases of the Clang compiler) that doesn't fully support C++11 (the standard where `std:thread` was added)? — Some programmer dude, Feb 14 '17 at 11:56
working here: cpp.sh/5w4z5 probalby you must check your compiler version — Netwave, Feb 14 '17 at 12:10
@ErikAlapää you were right, this fixed it. (if you post that as an answer i can accept it) — Nikolaj, Feb 14 '17 at 12:37

score 1 · Accepted Answer · answered Feb 14 '17 at 12:51

1

Depending on gcc version, you should add the compiler switch -std=c++11, or -std=c++0x.

answered Feb 14 '17 at 12:51

Erik Alapää

2,585
1
14
25

score 1 · Answer 2 · answered Feb 14 '17 at 13:02

1

I am able to compile it here

with C++14 and got output as below.

task1 says: Hello

Compile using -std=c++11 flag or above.

answered Feb 14 '17 at 13:02

Rishi

1,387
10
14

Calling threaded functions with arguments not possible

2 Answers2

Linked