Don't suppose you could add these in for dlexer.l too?  If not I'll raise a separate pull.
```
0x{H}+L   { return(TOKENIZER_LITERAL); }
0x{H}+U   { return(TOKENIZER_LITERAL); }
0x{H}+UL  { return(TOKENIZER_LITERAL); }
```

Also, you can catch exponent literals too (eg: 10e1).
```
{D}+[Ee]{D}+  { return(TOKENIZER_LITERAL); }
```
This rule can go into both clexer.l and dlexer.l - though have not tested the above.