Compiler Warning (level 4) C4816
TOC
Collapse the table of content
Expand the table of content
The document is archived and information here might be outdated

Compiler Warning (level 4) C4816

Error Message

'param' : parameter has a zero-sized array which will be truncated (unless the object is passed by reference)

A parameter to an object with a zero-size array was not passed by reference. The array will not get copied when the object is passed.

Example

The following sample generates C4816:

// C4816.cpp
// compile with: /W4
#include <stdio.h>

extern "C" int printf_s(const char *, ...);

#pragma warning(disable : 4200)

struct S1
{
    int i;
    char cArr[];
};

void TestErr(S1 s1)   // C4816 param with zero-array 
                      // not passed by reference
{
    printf_s("%d %c %c\n", s1.i, s1.cArr[0], s1.cArr[1]);
}

void TestOk(S1 &s1)
{
    printf_s("%d %c %c\n", s1.i, s1.cArr[0], s1.cArr[1]);
}

int main()
{
    S1 myS_1 = { 6, 'a', 'b', 'c' };
    TestErr(myS_1);
    TestOk(myS_1);
}
Show:
© 2016 Microsoft