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#include <new>
#include <utility>
#include <type_traits>
 
struct A
{
 
};
 
struct B
{
	int i;
};
 
template<typename T, typename U, typename... Args>
T* construct(U ptr, Args&&... args)
{
	static_assert(std::is_same<U, void*>::value or std::is_same<U, char*>::value, "must be void* or char*");
	return ::new(ptr) T(std::forward<Args>(args)...);
}
 
int main()
{
	A a;
	alignas(B) char area[sizeof(B)];
	void* ptr = area;
	construct<B>(&a); // fails at compile time
	construct<B>(&area[0]);
	construct<B>(ptr);
}

prog.cpp: In instantiation of 'T* construct(U, Args&& ...) [with T = B; U = A*; Args = {}]':
prog.cpp:27:17:   required from here
prog.cpp:18:2: error: static assertion failed: must be void* or char*
  static_assert(std::is_same<U, void*>::value or std::is_same<U, char*>::value, "must be void* or char*");
  ^

Standard output is empty