[U-Boot] [PATCH v7 03/23] Add abs() macro to return absolute value

[Wolfgang Denk]

Dear Simon Glass,

In message <1336685875-13177-4-git-send-email-sjg at chromium.org> you wrote:
> This macro is generally useful to make it available in common.

I agree with the idea of the patch, but I object against the
current implementation.

> +/* Return the absolute value of a number */
> +#define abs(x)	((x) < 0 ? -(x) : (x))

NAK.  This macro can have nasty side effects.  Consider something like

	foo = abs(bar++);

or

	foo = abs(in_be32(reg));

etc.

Why do you re-invent the wheel (poorly) instead of - for example -
copying the definition from Linux ("include/linux/kernel.h") ?

Best regards,

Wolfgang Denk

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