[PATCH] Add private_function for private functions within glibc [BZ #21598]

[Florian Weimer]

On 08/10/2017 02:44 PM, H.J. Lu wrote:

> It is OK to use __attribute__ ((regparm (3))) with CET as long as the
> function is hidden.  We need to at least keep __attribute__ ((regparm (1)))
> on ___tls_get_addr since it is the part of TLS ABI and we may have to
> support  __attribute__ ((regparm (3))) for lazy binding when CET is disabled
> forever.  Remove it from glibc doesn't buy us much.

It buys us peace of mind for those of us who do not work on i386 because
internal_function mismatches are a constant source of i386 build
failures.  I want to get rid of it because I think its presence is a
poor trade-off for the project as a whole.

We have to keep it for interfaces which are part of the ABI, of course,
but that is extremely special and confined to i386 code anyway.

Thanks,
Florian