Program "examples/miller.rb" fails to execute

[Jim Huang]

Test environment: Ubuntu Linux 14.04 x86_64

How to reproduce:

./lit examples/miller.rb

The last messages:

string addr> 147964944
...
memsz: 2
size: 911byte, 1.39%
Segmentation fault (core dumped)

[uint256_t]

I see. realloc() usage was incorrect. I fixed that bug:)

[Jim Huang]

Verified OK with commit d7b7c04 .

Thanks!