[PATCH 00/12] S390: Implement __fentry__

[Florian Weimer]

On 08/02/2018 09:57 AM, Ilya Leoshkevich wrote:
> This patch series adds the runtime support in glibc for the -mfentry
> gcc feature introduced in [1] and [2].
> 
> Patches 1-9 deal with avoiding clobbering %r0 when calling lazily bound
> functions, so that the new __fentry__ symbol could be called with return
> address in that register.

Should GCC arrange for suitable ABI markup if -mfentry is used?  I'm 
worried that unexpected clobbers of r0 could be quite difficult to 
figure out otherwise.

Thanks,
Florian