C typedef statements as host variables

supports the C typedef statements and allows the use of typedef names in declaring the types of host variables.

For example, the following code creates the smallint type as a short integer and the serial type as a long integer. It then declares a row_nums variable as an array of serial variables and a variable counter as a smallint. 
EXEC SQL BEGIN DECLARE SECTION;
   typedef short smallint; 
   typedef long serial;

   serial row_nums [MAXROWS];
   smallint counter;
EXEC SQL END DECLARE SECTION;

You cannot use a typedef statement that names a multidimensional array, or a union, or a function pointer, as the type of a host variable.