Build failures on OSX

[telemachus]

I'm unable to install mpack on OSX (details below), and it seems to be leading to a problem installing neovim (related to neovim/neovim#4573, I think).

Here's the output of the build failure:

$ luarocks install mpack
lmpack.c:185:11: warning: implicit declaration of function 'lua_objlen' is invalid in
      C99 [-Wimplicit-function-declaration]
    len = lua_objlen(L, -1);
          ^
lmpack.c:1056:14: error: unknown type name 'luaL_reg'; did you mean 'luaL_Reg'?
static const luaL_reg unpacker_methods[] = {
             ^~~~~~~~
             luaL_Reg
/usr/local/include/lauxlib.h:26:3: note: 'luaL_Reg' declared here
} luaL_Reg;
  ^
lmpack.c:1062:14: error: unknown type name 'luaL_reg'; did you mean 'luaL_Reg'?
static const luaL_reg packer_methods[] = {
             ^~~~~~~~
             luaL_Reg
/usr/local/include/lauxlib.h:26:3: note: 'luaL_Reg' declared here
} luaL_Reg;
  ^
lmpack.c:1068:14: error: unknown type name 'luaL_reg'; did you mean 'luaL_Reg'?
static const luaL_reg session_methods[] = {
             ^~~~~~~~
             luaL_Reg
/usr/local/include/lauxlib.h:26:3: note: 'luaL_Reg' declared here
} luaL_Reg;
  ^
lmpack.c:1077:14: error: unknown type name 'luaL_reg'; did you mean 'luaL_Reg'?
static const luaL_reg mpack_functions[] = {
             ^~~~~~~~
             luaL_Reg
/usr/local/include/lauxlib.h:26:3: note: 'luaL_Reg' declared here
} luaL_Reg;
  ^
lmpack.c:1092:3: warning: implicit declaration of function 'luaL_register' is invalid
      in C99 [-Wimplicit-function-declaration]
  luaL_register(L, NULL, unpacker_methods);
  ^
2 warnings and 4 errors generated.

Error: Build error: Failed compiling object lmpack.o

OSX: 10.10.5
lua: Lua 5.2.4 Copyright (C) 1994-2015 Lua.org, PUC-Rio
luarocks: 2.3.0

[justinmk]

lua 5.1 header defines:

#define luaL_reg        luaL_Reg

Looks like lua 5.2 removed that. I think we require luajit or lua 5.1.

[tarruda]

Should have been closed by #5