Is it a GNU Tools failure that PIE use ET_DYN and can't be distinguished from libraries?

[Carlos O'Donell]

On 03/18/2015 04:51 PM, Roland McGrath wrote:
>> Is it a failing of the tooling that we didn't provide a way for
>> tools to determine PIE vs. DSO?
> 
> It might be if we hadn't.  But we defined a PIE as an ET_DYN with a
> DT_DEBUG.  (We didn't account for a case that would be useful and the
> linker doesn't currently fully support: a static PIE, which is an ET_DYN
> that has no PT_INTERP and might not have a PT_DYNAMIC either.)

Interesting, ET_DYN + DT_DEBUG, I did not see that coming.

At best I'd have defined it as ET_DYN + PT_INTERP, and I would have
been happy to call libc.so.6 the first PIE.

>> Was it always the goal to be able to dlopen a PIE? e.g. Implement
>> both the daemon as a standalone executable and as a DSO you could
>> load and run as a service?
> 
> That was indeed a goal at the inception of PIE.

OK, thanks.

Cheers,
Carlos.