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Date: Fri, 27 Jan 2023 23:58:04 +0000
From: Joseph Myers <joseph@codesourcery.com>
To: Paul Eggert <eggert@cs.ucla.edu>
CC: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
	<libc-alpha@sourceware.org>
Subject: Re: time64 / Large File Support: 2) default time64 breaks legacy
 32bit binaries
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On Fri, 27 Jan 2023, Paul Eggert wrote:

> On 2023-01-27 09:40, Adhemerval Zanella Netto wrote:
> > > Another possibility is to adopt the milder approach for glibc version N,
> > > and switch to the more drastic approach in glibc version N+1.This would
> > > give distros time to test this new configure-time option before it's the
> > > default.
> > Do you mean add the --enable-hard-sys-types64 on glibc N, and then remove it
> > on
> > N+1 and make the 64-bit the default?
> 
> Sure, that would work. If that's too fast we could do something more gradual,
> like this:
> 
> 1. glibc version N supports --enable-hard-sys-types64 and
> --disable-hard-sys-types64 and the default is disabled.
> 
> 2. glibc version N+1 is the same, but the default is enabled.
> 
> 3. glibc version N+2 removes support for --disable-hard-sys-types64;
> --enable-hard-sys-type64 remains as a no-op.

One release is an extremely short time period for glibc (six months).  A 
few years between steps would seem better for something like this.

-- 
Joseph S. Myers
joseph@codesourcery.com