[U-Boot-Users] STD_C and STDC_

Wolfgang Denk wd at denx.de
Wed Dec 13 20:31:57 CET 2006

In message <457F6D37.0000CE.20237 at bj163app22.163.com> you wrote:
>    Everyone,I was reading the U-boot of the mpc8260 in recent months. And I was a freshman. Yesterday,When I was reading the U-boot1.1.4\include\malloc.h, I was puzzled by the ln223 and the ln224 (#ifndef _STD_C  #ifdef  _STDC_).

Your lines are too long. Please  make  sure  to  restrict  your  line
length to 70 characters or so.

> I don't understand the differeces between the  "_STD_C" and "_STDC_".Could anyone can help me?

The difference is in the order of the last two  characters.  In  your
first  string,  the  'C' is preceeded by the '_', while in the second
string the 'C' is followed by the '_'.

But I have to admit that I see no relation of this question to actual
U-Boot code, since neither of these strings is used in U-Boot.  Also,
only  one  of  the lines you referred to is a '#ifdef' statement; the
other one is a '#define' instead.

> --Boundary-=_CBfWamzZMGvDFyxcltoAEydEtpOl
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And please don't post HTML here.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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