luacurl build problem

[Dirk Laurie <dirk.laurie@...>]

$ sudo luarocks install luacurl
Installing http://www.luarocks.org/repositories/rocks/luacurl-1.2.1-1.src.rock...
Using http://www.luarocks.org/repositories/rocks/luacurl-1.2.1-1.src.rock...
switching to 'build' mode
Archive:  /tmp/luarocks_luarocks-rock-luacurl-1.2.1-1-7818/luacurl-1.2.1-1.src.rock
  inflating: luacurl-1.2.1-1.rockspec
 extracting: luacurl-1.2.1.zip
Archive:  luacurl-1.2.1.zip
   creating: luacurl-1.2.1/
  inflating: luacurl-1.2.1/CMakeLists.txt
  inflating: luacurl-1.2.1/luacurl.c
gcc -O2 -fPIC -I/usr/local/include -c luacurl.c -o luacurl.o -I/usr/include
luacurl.c:813:30: error: array type has incomplete element type
luacurl.c:823:30: error: array type has incomplete element type

$ lua -v
Lua 5.2.3  Copyright (C) 1994-2013 Lua.org, PUC-Rio

System: Ubuntu 12.04.3 LTS