Craps game rules and code
Try not to use using namespace std.
The parameters in main() are only necessary if you're executing from the command line.
You're not calling std::srand() nor including &lt;cstdlib&gt;.  However, if you're using C++11, both std::srand and std::rand are not recommended due to certain computational complications (the C++11 pseudo-random number generators can be found under &lt;random&gt;).  But, for a simple program, it may not matter.

In general, here's how to call std::srand():

// casting may just be necessary if warnings are generated
//     that will alert you if there's a possible loss of data
// prefer nullptr to NULL if using C++11
std::srand(static_cast&lt;unsigned int&gt;(std::time(NULL)));


Only include this once, preferably at the top of main().  This is preferred because


It'll help you keep track of it, especially if it'll need to be removed at some point.
If called repeatedly, you'll receive the "same random number" each time.

It's best to keep variables as close in scope as possible.  Here, dice1 and dice2 can be initialized in the while-loop:

unsigned int dice1 = rand() % 6 + 1;
unsigned int dice2 = rand() % 6 + 1;


roll, however, will need to stay where it is so that the loop will work.
The bool-checking can be shortened:

// these are similar
while (checkWinning(roll) == true)
while (checkWinning(roll))




// these are also similar
while (checkWinning(roll) == false)
while (!checkWinning(roll))

checkWinning() takes int roll, but roll is already unsigned int.  They should match.
checkWinning()'s closing curly brace shouldn't have a ;.  It's not a type.
bool winner seems redundant; just return true or false.  Also, the conditions seem a little unclear.  If the sum constitutes a win or a re-roll, how do you specifically distinguish the two?  They both return true.  I'd at least rename the function for clarification.  There's also a Boolean enum, but that may be overkill here (or even unnecessary as there are only two ending outcomes).
There should be a final outcome message, indicating a win or a loss.  Also, you're not giving the player the option to play another game if victorious (and until loss).