Re: Failures with exelib.exp testcase (was Re: minutes 2010-08-19)

[Roland McGrath <roland@redhat.com>]

> I see your point, but do we really need a runtime test? Can't we just
> have a check when reading in the elf file symbols, that just looks
> whether or not there is an .odp section?

To clarify, "runtime" means "runtime of the translator".  So you are not
suggesting doing a check in a different phase than what I said, just using
a different method of analyzing the user binary in question.

Why is it that you would prefer looking for an .odp section to looking at
the machine the binary is built for?

In general, ELF sections are not supposed to be a primary mechanism for
anything after final-link time.  It's a general rule in ELF that any time
you are basing something on a section name, you are doing it wrong.  It's
also always kosher for the link to have used a linker script that combined
several sections together, etc.  

The section name ".opd" is not part of the ppc64 ABI.  What is formally
said in the ABI is that the symbol name for a function (which I read to
mean any STT_FUNC symbol) that does not begin with a dot is the address of
the function descriptor.  Anyway, it is far simpler to check the header for
.e_machine == EM_PPC64 than to look for a particular section name.


Thanks,
Roland