Re: [boost] [#pragma once]

Subject: Re: [boost] [#pragma once]
From: Niels Dekker - address until 2010-10-10 (niels_address_until_2010-10-10_at_[hidden])
Date: 2009-04-11 04:56:07

Graham wrote:
> Incredibuild (xoreax) and other parallel compilation systems have problems with pragma once

Thanks, Graham! (We're using IncrediBuild very much, at LKEB.) Now I 
see, it's at their FAQ:
   "When a source file includes one or more header files that are also 
included by the precompiled header and use the '#pragma once' directive, 
these header files may be #included more than once despite the #pragma 
once directive" http://xoreax.com/support_faq.htm#q122

Bo Persson wrote:
> The #pragma once depends on the compiler being able to correctly parse 
> the include paths for all possibly attached file systems. If it fails, 
> it might include the same file twice from seemingly different paths.

I guess that's what typically might go wrong when using IncrediBuild, or 
other parallel compilation systems.

Kind regards, Niels
-- 
Niels Dekker
http://www.xs4all.nl/~nd/dekkerware
Scientific programmer at LKEB, Leiden University Medical Center