[LLVMdev] LLD improvement plan

[Chris Lattner]

On May 4, 2015, at 1:16 PM, Joerg Sonnenberger <joerg at britannica.bec.de> wrote:
> It has been said in this thread before, but I fail to see how the atom
> model is an actual improvement over the fine grained section model. It
> seems to be artifically restricted for no good reasons.

Sections come with a huge amount of bloat and overhead that atoms do not.

>> Lets stop thinking about lld as one linker, and instead think of it is
>> two different ones.  We’ll build a Camp B linker which is the best of
>> breed section based linker.  It will support linker scripts and do
>> everything better than any existing section based linker.  The first
>> step of this is to do what Rui proposes and rip atoms out of the model.
> 
> This is another item that has been irritating me. While it is a very
> laudable goal to not depend on linker scripts for the common case, not
> having the functionality of fine grained output control is certainly a
> problem. They are crucial for embedded developers and also at least
> significant for anything near a system kernel.

I’m not saying that the linker should eschew fine grained control, I’m saying it should dump linker scripts (and replace them with something better).  Are you going to argue that linker scripts are great, or that they are what we would end up with if we weren’t driven by backwards compatibility goals?

-Chris