Error: hammer ABI contains Genode-internal symbol '__bss_start'

[Christian Helmuth]

Hello Norman,

I'm unsure if you addressed me by your questions but...

On Thu, Jan 10, 2019 at 11:04:49AM +0100, Norman Feske wrote:
> I wonder, should we consider adding a black list of known Genode symbols
> to the abi_symbols tool? This would make the tool a bit more convenient.
> On the other hand, it may foster the (wrong) expectation that the output
> of the tool *is* an ABI as is. In practice, the manual curing step is
> important. E.g., symbols of library-internal interfaces should be
> removed. This step needs a human brain.

When writing my response I also tended to propose to add those symbols
to the tool but came to the same conclusion: The ABI ssymbols list is
the equivalent of an ordinary linker version script which explicitly
defines the exported symbols of dynamic libraries in traditional
systems. Therefore, the human-brain intervention during the ABI
creation should be at least emphasized if not enforced.

> Given Guido's question, we should definitely enhance the documentation
> about using the abi_symbols tool. Since Guido referred to the porting
> guide, would that document be a suitable place?

You're right, adding extended documentation of the tool usage to the
guide supports the goal mentioned above, but currently I'm somewhat
occupied by other labors to improve the documentation myself. Maybe
Guido could contribute some words based on his practical experiences?

Regards
-- 
Christian Helmuth
Genode Labs

https://www.genode-labs.com/ · https://genode.org/
https://twitter.com/GenodeLabs · /ˈdʒiː.nəʊd/

Genode Labs GmbH · Amtsgericht Dresden · HRB 28424 · Sitz Dresden
Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth