Message-ID: <3F6F6B1B.9040609@nortelnetworks.com>
Date: Mon, 22 Sep 2003 17:35:23 -0400
From: Chris Friesen <cfriesen@nortelnetworks.com>
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Subject: compiler warnings and syscall macros
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I'm trying to figure something out.  For ppc, in asm/unistd.h, 
__syscall_nr is defined as:


#define __syscall_nr(nr, type, name, args...)	\
	unsigned long __sc_ret, __sc_err;	\
	{					\
<snipped for brevity>
	}					\
	if (__sc_err & 0x10000000)		\
	{					\
		errno = __sc_ret;		\
		__sc_ret = -1;			\
	}					\
	return (type) __sc_ret


Whenever I use this in my code, I get compiler warnings about the 
statment "__sc_ret = -1" since it is assigning a negative value to an 
unsigned int.

Would it hurt anything if I put in an explicit cast, like this?

__sc_ret = (unsigned long) -1;

This seems to get rid of the warnings, and I can't imagine it hurting 
anything.

Am I missing something bad here?


Chris

-- 
Chris Friesen                    | MailStop: 043/33/F10
Nortel Networks                  | work: (613) 765-0557
3500 Carling Avenue              | fax:  (613) 765-2986
Nepean, ON K2H 8E9 Canada        | email: cfriesen@nortelnetworks.com

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