None.

This macro is a wrapper around NKDbgPrintfW that uses a subset of printf formatting characters to format debugging message output.

This macro may be used to conditionally output a debugging message formatted in printf style. The printf-style message parameter is output if the Boolean input expression evaluates to TRUE. Note that the parameter Message must be enclosed by parentheses to prevent syntax errors being generated by the preprocessor.

 DEBUGMSG(TRUE, (TEXT("Testing item count against maximum %u\r\n"),
         dwMaxNumberOfItems));
 DEBUGMSG(dwCurrentNumberOfItems >= dwMaxNumberOfItems,
          (TEXT("Invalid item count! Found %u, expected less than %u\r\n"),
           dwCurrentNumberOfItems, dwMaxNumberOfItems));

Output:

 Testing item count against maximum 68
 Invalid item count! Found 343, expected less than 68

Reference