From owner-freebsd-hackers  Mon May 14 23:49:11 2001
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Date: Tue, 15 May 2001 09:46:16 +0300
From: Valentin Nechayev <netch@iv.nn.kiev.ua>
To: Dima Dorfman <dima@unixfreak.org>
Cc: hackers@FreeBSD.ORG, bde@FreeBSD.ORG
Subject: Re: MIN()/MAX() definitions in sys/param.h
Message-ID: <20010515094616.B1835@iv.nn.kiev.ua>
References: <20010514071731.1D9F93E28@bazooka.unixfreak.org>
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In-Reply-To: <20010514071731.1D9F93E28@bazooka.unixfreak.org>; from dima@unixfreak.org on Mon, May 14, 2001 at 12:17:31AM -0700
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 Mon, May 14, 2001 at 00:17:31, dima (Dima Dorfman) wrote about "MIN()/MAX() definitions in sys/param.h": 

> Is there a reason the definitions of the MIN() and MAX() macros in
> sys/param.h are under an '#ifndef _KERNEL'?  Quite a few files in the
> kernel define these (well, at least MIN) themselves, so it would seem
> to make sense to define them globally in sys/param.h for the kernel as
> well.  Any reason this isn't already done this way, or should I come
> up with a patch to fix that?

gcc provides safe way to implement min()/max():

=== cut from info gcc ===
     #define max(a,b) \
       ({typedef _ta = (a), _tb = (b);  \
         _ta _a = (a); _tb _b = (b);     \
         _a > _b ? _a : _b; })
=== end cut ===

For kernel compiling you may rely on gcc and use such safe macros.
I'm unsure for the same statement about userland.


/netch

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