First draft of the Y2038 design document

[Joseph Myers]

On Mon, 26 Oct 2015, Florian Weimer wrote:

> On the glibc side, does symbol versioning really buy us that much?  It

What do you mean by symbol versioning here?

If you mean ELF symbol versioning, then obviously every new interface gets 
allocated the symbol version for the glibc version in which this support 
is added (e.g. GLIBC_2.24 if the support goes into 2.24).  That's 
completely standard for all glibc API additions - we keep supporting old 
binaries while ensuring binaries using new interfaces fail loudly when run 
with old glibc.

If you mean the separate versioning system for struct stat referred to on 
that wiki page (inlines / libc_nonshared functions calling *xstat* 
functions with an explicit version number argument): I suspect this system 
is in a sense obsolete given ELF symbol versioning (but predates it) - but 
given that this is in use for existing struct stat interfaces, I think it 
would be excessively confusing to use it for existing stat interfaces but 
not for the corresponding ones using 64-bit time_t.

-- 
Joseph S. Myers
joseph@codesourcery.com