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Subject: Re: [RFC PATCH] asm-generic: Unify uapi bitsperlong.h
From:   Xi Ruoyao <xry111@xry111.site>
To:     Tiezhu Yang <yangtiezhu@loongson.cn>, Arnd Bergmann <arnd@arndb.de>
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Date:   Fri, 09 Jun 2023 21:05:07 +0800
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On Fri, 2023-06-09 at 14:50 +0800, Tiezhu Yang wrote:

/* snip */

> > > > In musl, the documentation states that at least gcc-3.4 or
> > > > clang-3.2 are required, which probably predate the
> > > > __SIZEOF_LONG__ macro.

Indeed, I've digged some history and __SIZEOF_LONG__ was added into GCC-
4.3 (in 2008).  And I didn't realize the bitsperlong.h in tools
directory is a copy from uapi.

> > > > On the other hand, musl was only
> > > > released in 2011, and building musl itself explicitly
> > > > does not require kernel uapi headers, so this may not
> > > > be too critical.

> Only arm64, riscv and loongarch belong to the newer architectures
> which are related with this change, I am not sure it is necessary
> to "unify" uapi bitsperlong.h for them.

At least it will stop the engineers working on "the next architecture"
from adding an unneeded bitsperlong.h :).


--=20
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University