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From: bill_carson@126.com (rocky)
To: linux-arm-kernel@lists.infradead.org
Subject: Query about cplusplus in linkage.h
Date: Sat, 20 Nov 2010 12:17:02 +0800 (CST)	[thread overview]
Message-ID: <13701df.df91.12c677fe0fd.Coremail.bill_carson@126.com> (raw)

Hi, all

I am a little confused about the following definition :

--------------include/linux/linkage.h-----------
#ifdef __cplusplus
#define CPP_ASMLINKAGE extern "C"
#else
#define CPP_ASMLINKAGE
#endif

#ifndef asmlinkage
#define asmlinkage CPP_ASMLINKAGE
#endif

all system call functions are marked with asmlinkage, as well as other kernel function like printk/schedule/do_softirq


so every asmlinkage function has extern "C"  attribute if cplusplus is defined, which definitely happens  when compiling C++ code.

I dont get it when cplusplus is needed when compiling kernel?

Can anyone help me out of this little misunderstanding?

Thansk




		

             reply	other threads:[~2010-11-20  4:17 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-20  4:17 rocky [this message]
2010-11-22  8:30 ` Query about cplusplus in linkage.h Baruch Siach
2010-11-22 15:07   ` rocky
2010-11-23  5:46     ` Baruch Siach
2010-11-23  6:06       ` rocky

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