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  1. #include <cstdint>
  2. #include <iomanip>
  3. #include <iostream>
  4.  
  5. long l[5];
  6. char * c = reinterpret_cast<char*>(l);
  7.  
  8. void print()
  9. {
  10. 	for (int r = 0; r != sizeof(l)/sizeof(l[0]); ++r)
  11. 	{
  12. 		long value = l[r];
  13. 		const char * bytes = reinterpret_cast<char*>(&value);
  14.  
  15. 		std::cout << "Array index " << r << ": ";
  16. 		for (int c = 0; c != sizeof(l[0]); ++c)
  17. 		{
  18. 			if (c != 0)
  19. 			{
  20. 				std::cout << " ";
  21. 			}
  22. 			std::cout << std::setw(2) << std::setfill('0') << static_cast<int>(bytes[c]);
  23. 		}
  24. 		std::cout << std::endl;
  25. 	}
  26. 	std::cout << std::endl;
  27. }
  28.  
  29. int main()
  30. {
  31. 	long & aligned = *reinterpret_cast<long*>(&c[0]);
  32. 	long & misaligned = *reinterpret_cast<long*>(&c[2*sizeof(long) - 1]); // misaligned	
  33.  
  34.  
  35. 	std::cout << "aligned: " << aligned << std::endl;
  36. 	std::cout << "misaligned: " << misaligned << std::endl;
  37. 	print();
  38.  
  39. 	aligned = 1;
  40. 	misaligned = 2;
  41.  
  42. 	std::cout << "aligned: " << aligned << std::endl;
  43. 	std::cout << "misaligned: " << misaligned << std::endl;
  44. 	print();
  45.  
  46. 	int n = 0;
  47. 	short * s = reinterpret_cast<short*>(&n);
  48.  
  49. }
Success #stdin #stdout 0s 2884KB
comments (?)
stdin 
Standard input is empty
stdout 
aligned: 0
misaligned: 0
Array index 0: 00 00 00 00
Array index 1: 00 00 00 00
Array index 2: 00 00 00 00
Array index 3: 00 00 00 00
Array index 4: 00 00 00 00

aligned: 1
misaligned: 2
Array index 0: 01 00 00 00
Array index 1: 00 00 00 02
Array index 2: 00 00 00 00
Array index 3: 00 00 00 00
Array index 4: 00 00 00 00
https://ideone.com/ubmb9
language:
C++14 (gcc 8.3)
created:
11 years ago
visibility:
public

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