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When an exception is thrown, control is transferred to the nearest handler with a type that matches the type of the exception thrown. If no matching handler is directly found within the handlers for a try block in which the exception is thrown, the search for a matching handler continues to dynamically search for handlers in the surrounding try blocks of the same thread. The C++ Standard, [except.handle], paragraph 9 [ISO/IEC 14882-2014], states the following:

If no matching handler is found, the function std::terminate() is called; whether or not the stack is unwound before this call to std::terminate() is implementation-defined.

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In this compliant solution, the main entry point handles all exceptions, which ensures that the stack is unwound up to the main() function and allows for graceful management of external resources:.

void throwing_func() noexcept(false);
 
void f() {
  throwing_func();
}
 
int main() {
  try {
    f();
  } catch (...) {
    // Handle error
  }
}

...

In this compliant solution, the thread_start() handles all exceptions and does not rethrow, allowing the thread to terminate normally:.

#include <thread>

void throwing_func() noexcept(false);

void thread_start(void) {
  try {
    throwing_func();
  } catch (...) {
    // Handle error
  }
}

void f() {
  std::thread t(thread_start);
  t.join();
}

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