[PATCHv3] powerpc: ABI change - add HWCAP/HWCAP2/platform info to TCB

[Carlos Eduardo Seo]

O’Donell suggested we used a versioned symbol to track this change, so it doesn’t break applications when running against an old glibc:

> > I have only a few substantive technical issues with the patch. Given
> > that the ABI allocates a large block of tp+offset data, I think it is
> > OK for IBM to use the data in this way. For example I think it is much
> > much more serious that such a built application will likely just crash
> > when run with an older glibc. This is a distribution maintenance issue
> > that I can't ignore and I'd like to see it solved by a dependency on a
> > versioned dummy symbol.

See: https://sourceware.org/ml/libc-alpha/2015-07/msg00196.html

Thanks,

-- 
Carlos Eduardo Seo
Software Engineer - Linux on Power Toolchain
cseo@linux.vnet.ibm.com

> On Sep 23, 2015, at 6:15 PM, Joseph Myers <joseph@codesourcery.com> wrote:
> 
> Why do you need a public symbol init_hwcapinfo?  If this function is 
> called from outside the library that defines it, I'd have expected a 
> private, implementation-namespace symbol __init_hwcapinfo, at version 
> GLIBC_PRIVATE.  A public symbol should only be needed if it's a documented 
> API for users to call.
> 
> -- 
> Joseph S. Myers
> joseph@codesourcery.com
>