Fifth draft of the Y2038 design document

[Joseph Myers]

On Wed, 8 Mar 2017, Albert ARIBAUD wrote:

> > > > - 'clock_gettime' redirects to '__clock_gettime'.    
> > > 
> > > No, it doesn't redirect.  User application code is compiled to .o files 
> > > that reference clock_gettime, not __clock_gettime.  __clock_gettime is a 
> > > GLIBC_PRIVATE symbol, only for internal use by glibc libraries when 
> > > required for namespace reasons, not for application code.  Whereas 

> Assume one single source file (say, app.c) which includes <time.h> and
> refers to 'clock_gettime'. This source code is compiled into two object
> modules, one with -DTIME_BITS=64 (sayn app64.o) and one without (say,
> app32.o). Both object modules expect to be linked and run against the
> (same) GLIBC dynamic library. For the app32.o module, we expect its
> call to 'clock_gettime' to end up executing '__clock_gettime' while for
> the app64.o module, we expect its 'clock_gettime' call to end up
> executing '__clock_gettime64'.

As I said above, no user .o file should ever end up referencing 
__clock_gettime; that's a purely internal symbol, not a public ABI.

-- 
Joseph S. Myers
joseph@codesourcery.com