Dead code not optimized away by the compiler?

Hi,

With the Intel Compiler version 16.0.1 on OSX, the following code

#include <cstdio>
#include <cstdlib>
#include <new>
#include <type_traits>

template <typename T>
class Test {
 private:
  T* data_;

 public:
  Test(int n);
  ~Test();
};

template <typename T>
Test<T>::Test(int n) {
  if (std::is_pod<T>::value) {
    data_ = new T[n];
  } else {
    data_ = static_cast<T*>(::operator new(n * sizeof(T)));
    for (int i{0}; i < n; ++i) {
      new (data_ + i) T{};
    }
  }
};

template <typename T>
Test<T>::~Test() {
  if (std::is_pod<double>::value) {
    delete[] data_;
  } else {
    ::operator delete(data_);
  }
};

int main(int argc, const char* argv[]) {
  Test<double> x{10};

  return 0;
}

compiled with

icpc -std=c++11 -O3 -xHost -ansi-alias -fno-exceptions -DNDEBUG -opt-report=3 main.cpp -o main

produces an optimization report where it is clear that the call to ::operator new is still present in the optimization report although it is clear that at compile time, we now that this code is dead code.

INLINE REPORT: (main(int, const char **)) [1] main.cpp(37,40)
  -> INLINE (MANUAL): (38,18) Test<double>::Test(Test<double> *, int)
    -> EXTERN: (19,20) operator new[](size_t)
    -> INLINE (MANUAL): (23,12) operator new(size_t, void *)
  -> INLINE (MANUAL): (40,3) Test<double>::~Test(Test<double> *)
    -> EXTERN: (31,5) operator delete[](void *)

I suspect this is an optimization bug of the Intel compiler. But it seems that the assembly does not contain any code related to operator new.

Best regards,

Francois