C:\test>792136.pl
Benchmark: timing 1 iterations of list, ref...
      list:  0 wallclock secs ( 0.05 usr +  0.00 sys =  0.05 CPU) @ 21.28/s (n=1)
            (warning: too few iterations for a reliable count)
       ref:  0 wallclock secs ( 0.03 usr +  0.00 sys =  0.03 CPU) @ 32.26/s (n=1)
            (warning: too few iterations for a reliable count)
2000001000000
2000001000000

C:\test>792136.pl
Benchmark: timing 1 iterations of list, ref...
      list:  0 wallclock secs ( 0.05 usr +  0.00 sys =  0.05 CPU) @ 21.28/s (n=1)
            (warning: too few iterations for a reliable count)
       ref:  0 wallclock secs ( 0.03 usr +  0.00 sys =  0.03 CPU) @ 31.25/s (n=1)
            (warning: too few iterations for a reliable count)
2000001000000
2000001000000

C:\test>792136.pl
Benchmark: timing 1 iterations of list, ref...
      list:  0 wallclock secs ( 0.05 usr +  0.00 sys =  0.05 CPU) @ 21.28/s (n=1)
            (warning: too few iterations for a reliable count)
       ref:  0 wallclock secs ( 0.03 usr +  0.00 sys =  0.03 CPU) @ 31.25/s (n=1)
            (warning: too few iterations for a reliable count)
2000001000000
2000001000000


##</code><code>##

#define OPCODE U16

#ifdef PERL_MAD
#  define MADPROP_IN_BASEOP	MADPROP*	op_madprop;
#else
#  define MADPROP_IN_BASEOP
#endif

typedef unsigned int PERL_BITFIELD16; /// <<< I added this!
typedef PERL_BITFIELD16 Optype;