gregset vs prgregset vs elf_gregset in thread_db

Daniel Jacobowitz dmj+@andrew.cmu.edu
Mon Jun 25 19:06:00 GMT 2001


On Mon, Jun 18, 2001 at 12:06:08PM -0700, Daniel Jacobowitz wrote:
> The thread-db routines are defined to take arguments of type 'prgregset_t'. 
> On about half the supported architectures, prgregset_t is typedef'd to be
> 'gregset_t'; on the other half it is 'elf_gregset_t'.  I don't know where
> the gregset_t definitions came from, especially on platforms that have
> always been ELF, but they are substantially less useful than their elf
> counterparts - what we really want to fill in is the data we can get from
> ptrace, and pt_regs is usually fairly similar to an elf_gregset_t and an
> elf_fpregset_t.
> 
> For instance, on PowerPC the NIP is not in any of r0 - r31, and a gregset_t
> only has 32 elements.  No way to convey the thread's NIP, which makes
> debugging all but meaningless.
> 
> The only consumer of the prgregset_t and prfpregset_t types is thread-db. 
> Is there any objection to changing them to the elf_* variants, and possibly
> bumping the thread-db soname?  Although I'm not sure the latter is even
> necessary; gdb is the only consumer of thread-db I've ever found on linux,
> and it doesn't work with threads on the architectures affected yet anyway.

It seems that no one had any comments about this at all.  I'll submit a
patch shortly to change the typedefs, then, and see if that gets a
little more reaction.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer



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