V201. Explicit conversion from 32-bit integer type to memsize type

15.12.2011

It informs about the presence of the explicit type conversion from 32-bit integer type to memsize type which may hide one of the following errors: V101, V102, V104, V105, V106, V108, V109. You may address to the given warnings list to find out the cause of showing the diagnosis message V201.

The V201 warning applied to conversions of 32-bit integer types to pointers before. Such conversions are rather dangerous, so we singled them out into a separate diagnostic rule V204.

Keep in mind that most of the warnings of this type will be likely shown on the correct code. Here are some examples of the correct and incorrect code on which this warning will be shown.

The examples of the incorrect code.

int i;
ptrdiff_t n;
...
for (i = 0; (ptrdiff_t)(i) != n; ++i) {   //V201
  ...
}

unsigned width, height, depth;
...
size_t arraySize = size_t(width * height * depth);   //V201

The examples of the correct code.

const size_t seconds = static_cast<size_t>(60 * 60);   //V201
unsigned *array;
...
size_t sum = 0;
for (size_t i = 0; i != n; i++) {
  sum += static_cast<size_t>(array[i] / 4);   //V201
}
unsigned width, height, depth;
...
size_t arraySize =
size_t(width) * size_t(height) * size_t(depth);    //V201