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To: Sam James <sam@cmpct.info>
Cc: Kaz Kylheku <kaz@kylheku.com>,
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From: Paul Eggert <eggert@cs.ucla.edu>
Organization: UCLA Computer Science Department
Subject: Re: Best practices in regard to -D_TIME_BITS=64
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On 1/4/22 16:53, Sam James wrote:

> FWIW, we've hit issues in Gentoo with wget/gnutls: 
> https://bugs.gentoo.org/828001 <https://bugs.gentoo.org/828001>.

Thanks for the heads-up.

Yes, not surprised about that, as mixing 64-bit time_t apps with 32-bit 
time_t libraries is a recipe for trouble if the APIs depend on time_t. 
For apps that use such libraries, it really has to be a big bang: 
configure all that stuff with --disable-year2038 -D_TIME_BITS=32 before, 
and with --enable-year2038 CFLAGS=-D_TIME_BITS=64 after.

> https://wiki.gentoo.org/wiki/Project:Toolchain/time64_migration 

Thanks. The musl notes look helpful there.