Error: static assertion failed: std::thread arguments must be invocable after conversion to rvalues

The error message “static assertion failed: std::thread arguments must be invocable after conversion to rvalues”
is indicating that there is an issue with the arguments passed to the std::thread constructor. The issue is likely related to the type or format of the arguments being provided.

In C++, the std::thread constructor requires the provided arguments to be callable objects (i.e., objects that can be invoked as functions).
Additionally, it expects these callable objects to be convertible to rvalues, which means they can be treated as temporary objects that are bound to the thread and will be executed asynchronously.

Let’s take an example to illustrate this error. Consider the following code snippet:

“`cpp
#include
#include

void foo(int x)
{
std::cout << "Hello from thread: " << x << std::endl; } int main() { int value = 10; std::thread t(&foo, value); // Error: static assertion failed t.join(); return 0; } ```

In this example, we have a simple function foo that takes an integer argument and prints a message. In the main function, we attempt to create a new thread using std::thread and pass the function foo as well as the variable value as arguments.

However, this code will result in the error message mentioned in the query because the variable value is not an rvalue. The std::thread constructor expects the arguments to be convertible to rvalues.
To fix this issue, we need to use std::move to convert the argument into an rvalue, as shown below:

“`cpp
#include
#include

void foo(int x)
{
std::cout << "Hello from thread: " << x << std::endl; } int main() { int value = 10; std::thread t(&foo, std::move(value)); t.join(); return 0; } ```

By using std::move on the value argument, we ensure that it is treated as an rvalue and can be bound to the thread for execution. Now, the code will compile successfully without any errors.