Re: [PATCH] Fix GDB internal error by using text (instead of data) section offset

[Tom Tromey <tom@tromey.com>]

Kevin>     #3  0x000000000097c630 in stap_probe::get_relocated_address (this=0xa1a17a0,
Kevin> 	objfile=0x4fa48f0)
Kevin> 	at gdb/stap-probe.c:1341

One oddity here is that get_relocated_address calls this->get_address(),
which returns m_address, which is documented as:

  /* The address where the probe is inserted, relative to
     SECT_OFF_TEXT.  */
  CORE_ADDR m_address;

So using SECT_OFF_DATA here seems wrong in the first place.

Kevin> The obvious solution is to use some other section offset instead - as
Kevin> I recall, on Linux, the section offsets (for those sections which
Kevin> exist) will all be the same.

Is this a Linux thing or an ELF thing?  I don't know.

Kevin> So, what happens if there's no .text section?

Not probe-related but this is already a way to crash gdb:

https://sourceware.org/bugzilla/show_bug.cgi?id=19342
https://sourceware.org/bugzilla/show_bug.cgi?id=25678

... which is why I was curious about the ELF thing.  Like perhaps this
could all be made more robust somehow.

Your patch seems fine to me, though I don't have any idea if the dtrace
part is correct.

Tom