Date:   Mon, 29 Nov 2021 12:58:53 +0100
From:   Cyril Hrubis <chrubis@suse.cz>
To:     David Laight <David.Laight@ACULAB.COM>
Cc:     'David Howells' <dhowells@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-api@vger.kernel.org" <linux-api@vger.kernel.org>,
        "ltp@lists.linux.it" <ltp@lists.linux.it>,
        "libc-alpha@sourceware.org" <libc-alpha@sourceware.org>,
        "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
        "arnd@arndb.de" <arnd@arndb.de>
Subject: Re: [PATCH] uapi: Make __{u,s}64 match {u,}int64_t in userspace
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Hi!
> > > This changes the __u64 and __s64 in userspace on 64bit platforms from
> > > long long (unsigned) int to just long (unsigned) int in order to match
> > > the uint64_t and int64_t size in userspace.
> 
> That is a massive UAPI change you can't do.

Understood.

However it can still be changed if user asks for it explicitly right?

What about guarding the change with __STDINT_COMPATIBLE_TYPES__ as:

#if defined(__STDINT_COMPATIBLE_TYPES__)
# include <stdint.h>

typedef __u64 uint64_t;
...

#else
# include <asm-generic/int-ll64.h>
#endif

-- 
Cyril Hrubis
chrubis@suse.cz