From: Neil Brown <neilb@suse.de>
To: Steven Rostedt <rostedt@goodmis.org>
Date: Tue, 8 Nov 2005 12:18:42 +1100
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Cc: linas <linas@austin.ibm.com>, linux-kernel@vger.kernel.org,
       bluesmoke-devel@lists.sourceforge.net,
       linux-pci@atrey.karlin.mff.cuni.cz, johnrose@austin.ibm.com,
       linuxppc64-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>,
       Greg KH <greg@kroah.com>
Subject: Re: typedefs and structs [was Re: [PATCH 16/42]: PCI:  PCI Error
	reporting callbacks]
In-Reply-To: message from Steven Rostedt on Monday November 7
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On Monday November 7, rostedt@goodmis.org wrote:
> 
> This was for the simple reason, too many developers were passing
> structures by value instead of by reference, just because they were
> using a type that they didn't realize was a structure. And to make
> things worse, these structures started to get bigger.
> 

Another reason  for not using typedefs is that if you do, and you want
to refer to the structure in some other include file, you have to
#include the include file that devices the structure.
If you don't use typedefs, you can just say:

   struct foo;

and the compiler will happily wait for the complete definition later
(providing it doesn't need the size in the meanwhile). 
So avoiding typedef means that you can sometimes avoid excess
#includes, which means faster compiling.

NeilBrown
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