C6306
Note
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warning C6306: incorrect call to <function>: consider using <function> which accepts a va_list as an argument
This warning indicates an incorrect function call. The printf family includes several functions that take a variable list of arguments; however, these functions cannot be called with a va_list argument. There is a corresponding vprintf family of functions that can be used for such calls. Calling the wrong print function will cause incorrect output.
Example
The following code generates this warning:
#include <stdio.h>
#include <stdarg.h>
void f(int i, ...)
{
va_list v;
va_start(v, i);
//code...
printf("%s", v); // warning 6306
va_end(v);
}
To correct this warning, use the following code:
#include <stdio.h>
#include <stdarg.h>
void f(int i, ...)
{
va_list v;
va_start(v, i);
//code...
vprintf_s("%d",v);
va_end(v);
}