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  1. //http://stackoverflow.com/questions/28524896/casting-pointer-to-memory-buffer-to-pointer-to-vla
  2. #include <stdio.h>
  3. #include <stdlib.h>
  4.  
  5. int *getPointer(int num){
  6.     return malloc(sizeof(int) * num);
  7. }
  8.  
  9. void test1()
  10. {
  11.     #define ARRSIZE 6
  12.     int *pointer = getPointer(ARRSIZE);
  13.     int (*arrPointer)[ARRSIZE] = (int(*)[ARRSIZE])pointer;
  14.     printf("%d\n", sizeof(*arrPointer) / sizeof((*arrPointer)[0]));
  15. }
  16.  
  17. void test2( int arrSize )
  18. {
  19.     int *pointer = getPointer(arrSize);
  20.     int (*arrPointer)[arrSize] = (int(*)[arrSize])pointer;
  21.     printf("%d\n", sizeof(*arrPointer) / sizeof((*arrPointer)[0]));
  22. }
  23.  
  24. int main()
  25. {
  26. 	test1();
  27. 	test2( 5 );
  28. 	test2( 3 );
  29.     return 0;
  30. }
  31.  
Success #stdin #stdout 0s 2008KB
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Standard input is empty
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6
5
3
https://ideone.com/AI4yYB
C variable length array
language:
C (gcc 8.3)
created:
11 years ago
visibility:
public

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