Re: Error compilling Lua-SDL2

[Philipp Janda <siffiejoe@...>]

Am 23.06.2014 16:32 schröbte Bernd Eggink:
> On 23.06.2014 12:22, Bernd Eggink wrote:
> > When I tried to compile Lua-SDL2-2.0.3-1 on 64-bit Linux, I got:
> >
> > -----
> > /usr/bin/ld: /usr/bin/liblua.a(lapi.o): relocation R_X86_64_32 against
> > `luaO_nilobject_' can not be used when making a shared object; recompile
> > with -fPIC
> > /usr/bin/liblua.a: could not read symbols: Bad value
> > -----
> >
> > This went away after re-compiling Lua with -fPIC, but I'm not sure about
> > the consequences.

On Linux it is customary to let the Lua interpreter re-export the Lua 
API to extension modules. `make linux` will take care of this. The 
extension modules _don't_ link to `liblua.a` (or `liblua.so`), so the 
Lua library doesn't need to be position independent code (but it won't 
hurt if it is).

> Argh, meanwhile I noticed some consequences... For eaxmple, require
> "posix" leads to
>
> /usr/bin/lua: error loading module 'posix_c' from file
> '/usr/lib/posix_c.so':
>          dynamic libraries not enabled; check your Lua installation

Since dynamic libraries are not available in ISO C you need a 
preprocessor macro when compiling Lua: `LUA_USE_DLOPEN`. Again, the 
default Makefile should take care of this when invoked via `make linux`.

> And 'luarocks help' outputs:
>
> lua: /usr/share/lua/5.2/luarocks/loader.lua:12: attempt to call global
> 'module' (a nil value).

Older versions of LuaRocks need `LUA_COMPAT_MODULE` defined when 
building Lua 5.2 (`make linux` should do the trick). Either update 
LuaRocks, or compile Lua with `LUA_COMPAT_MODULE` defined.

> So I re-re-compiled Lua without -fPIC, and my Lua-SDL2 problem persists.
>
> - Bernd

Philipp