Question

I want to pass in an array of parameters to SQLBindParameters, and have this array held in a char array(since I don’t know the type beforehand) (I want all the elements in the ‘array’ to be the same).

I’ll have a pointer to a sample parameter type, and the size of the parameter.

void *buffer = getBuffer();
int bufferLength = getBufferLength();
const int numElements = 200; //for example

char *array = new char[bufferLength * numElements];

for(int i=0; i < numElements; ++i)
{
    memcpy(array + (i * bufferLength), buffer, bufferLength)
}

// now use array in SQLBindParameter call    

will this work as expected, without any alignment issues? (i.e., the same as if I had just declared an array of the right type to start with)

Answer 1

Assuming that you’re using vector with an allocator that uses operator new under the hood, then the C++ standard guarantees that an array of char allocated with new will be aligned suitably for use with any data type.

EDIT: Yes, new char[] is guaranteed to be aligned for use with any type.

EDIT2: Do note that a local (stack) array char foo[] has no such alignment guarantees.