gdbarch_skip_solib_resolver question

[Michael Eager]

On 01/11/2012 12:43 AM, Mark Kettenis wrote:
>>   I noticed that gdbarch_skip_solib_resolver() invokes
>>   glibc_skip_solib_resolver() on x86, mips, and sh to identify
>>   that gdb is stepping into _dl_runtime_resolve.
>>
>>   On PowerPC, gdbarch_skip_solib_resolver() always returns a zero.
>>
>>   I don't see any problem with gdb stopping in _dl_runtime_resolve
>>   or not stepping over the routine.
>>
>>   So, what does this mean?  Is calling glibc_skip_solib_resolver()
>>   optional?  Or is the handle_inferior_event() code so convoluted
>>   or intelligent that it works even when pieces are missing?
>>
>
> If I remember correctly, gdbarch_skip_solib_resolver() is just an
> optimization.  If it returns an address where GDB can set a breakpoint
> that gets hit upon return from the dynamic linker.  If
> gdbarch_skip_solib_resolver() returns zero GDB just single-steps through
> the dynamic linker, which works, but is a bit slower.

OK, that matches what I see.  Except that gdb always steps over the
call and never stops in the target function.


-- 
Michael Eager	 eager@eagercon.com
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