Experimental Physics and
Industrial Control System

On 07/05/2017 06:45 PM, Andrew Johnson wrote:
> There are tools which can edit the RPATH setting in an ELF binary, but
> IIRC they can only shorten the path, never make it longer.

There is at least one utility 'patchelf' which does not have this
limitation.

> That's an
> indication to me that what they are doing probably isn't completely
> kosher,

ELF is a fairly complicated format with lots of cross linking between
sections.  My guess is that other/older tools don't go to the trouble of
making all the necessary changes to re-layout the section holding the
rpath string.

> and I would rather not rely on arbitrary limits such as the
> length of the RPATH that we first compile in. Until the standard GNU
> binutils programs (objcopy and/or elfedit) provide a way to change an
> RPATH I would be reluctant to use this approach in Base itself.

I won't argue with this reluctance.  I also don't like the idea of
supporting something like patchelf.  One reason being that this doesn't
help with OSX and Mach binaries.