Re: [PATCH v2 1/1] gdb: Preserve IFUNC marker when finding inferior functions

[Simon Marchi <simark@simark.ca>]

On 6/30/26 11:29 AM, Wilco Dijkstra wrote:
> Hi Muhammad,
> 
>> Yes.  GDB should prefer the cache/GOT path and avoid resolver calls
>> where possible.  The patch does not make resolver calls safer or add a
>> new resolver-calling mechanism; it just preserves the IFUNC marker so
>> the existing IFUNC resolution path is used instead of calling the
>> resolver address as though it were malloc itself.
> 
> Indeed - while the patch works for now as a workaround, directly calling
> ifunc resolvers without following the ifunc ABI does not work. GDB only
> passes HWCAP as the first argument, so the resolver may return different
> functions due to the set of HWCAP values given not being identical between
> GDB and GLIBC (ie. It could call the wrong malloc implementation that was
> not selected or initialized).
> 
> So the best option is to call dlsym() as Florian suggested.

To track this, could either of you file a GDB bug with the necessary
background (why it would be good to switch to using to dlsym to resolve
ifuncs)?

Thanks,

Simon