[Buildroot] [PATCH 2/2] swupdate: support for Lua 5.1 is broken

["Jörg Krause" <joerg.krause@embedded.rocks>]

Hi Thomas,

On Tue, 2017-08-01 at 19:10 +0200, Thomas Petazzoni wrote:
> Hello,
> 
> On Mon, 31 Jul 2017 23:18:00 +0200, J?rg Krause wrote:
> > Before commit 87b6ac1478821351c92f7ca1c3154550e4713b28 support for
> > Lua
> > was always disabled by the default config file:
> > 
> > ```
> > CONFIG_LUA is not set
> > ```
> > 
> > The commit removed this setting and Lua support is now enabled if a
> > Lua
> > interpreter is enabled. As the swupdate build system uses pkg-
> > config to check
> > for the lua library by default (LUAPKG="lua") this throws a lot of
> > undefined referenced in case LuaJIT is uses as Lua interpreter,
> > e.g.:
> > 
> > ```
> > corelib/lib.a(lua_interface.o): In function `l_info':
> > lua_interface.c:(.text.l_info+0x14): undefined reference to
> > `luaL_checklstring'
> > ```
> > 
> > However, since version 2017.07 support for Lua 5.1 is broken in
> > swupdate. Therefore,
> > remove support for Lua 5.1 and LuaJIT in the swupdate package for
> > now
> > until upstream might fix this issue.
> 
> Isn't it better to revert the bump to 2017.07 instead of removing
> functionality that people could be relying on ?

Lua 5.1 and LuaJIT were never supported if CONFIG_HANDLER_IN_LUA was
selected. Upstream changed the functionality that the Lua code used
when enabling CONFIG_HANDLER_IN_LUA is now used in more common places
and therefore enabled if CONFIG_LUA is enabled.

That's why, I should have reword the commit message to: "Lua 5.1 is not
supported" instead of "broken".

I am asking the Stefano Babic, the swupdate maintainer, if he is
interested in enabling Lua 5.1 support. For now, swupdate is explicitly
tested using Lua 5.3.

Best regards,
J?rg Krause