C6383
Note
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warning C6383: buffer overrun due to conversion of an element count into a byte count: an element count is expected for parameter <number> in call to <function>
This warning indicates that a non-constant byte count is being passed when an element count is required. Typically, this occurs when a variable is multiplied by the sizeof
a type, but code analysis suggests that an element count is required.
Example
The following code generates this warning:
#include <string.h>
void f( wchar_t* t, wchar_t* s, int n )
{
// code...
wcsncpy (t, s, n*sizeof(wchar_t)); // warning 6383
// code ...
}
To correct this warning, do not multiply the variable with the sizeof
a type as shown in the following code:
void f( wchar_t* t, wchar_t* s, int n )
{
// code
wcsncpy (t, s, n);
// code ...
}
The following code corrects this warning by using the safe string manipulation function:
void f(wchar_t* t, wchar_t* s, size_t n)
{
// code...
wcsncpy_s( t, sizeof(s), s, n );
// code...
}
See Also
strncpy_s, _strncpy_s_l, wcsncpy_s, _wcsncpy_s_l, _mbsncpy_s, _mbsncpy_s_l
sizeof Operator