John-Mark Gurney wrote:
Tofig Suleymanov wrote this message on Thu, Aug 17, 2006 at 17:10 +0500:
is there anybody to explain why do we have infinite loop inside of
USB_ATTACH_SETUP macros inside of usb_port.h ? How does his loop gets
escaped when we use it in some usb driver ?
#define USB_ATTACH_SETUP \
do { \
sc->sc_dev = self; \
device_set_desc_copy(self, devinfo); \
device_printf(self, "%s\n", devinfo); \
} while (0);
The real bug here is the extra ; after the while(0) part... because
if you use it as such:
if (case)
USB_ATTACH_SETUP;
else
somethingelse;
you will get a compile error due to the double semicolon...
yes style(9) specifies this form of macro should NOT have the semicolon.
In cases like this, it is also common to have parens after the macro
name so that it looks like a function, and not a simple expresion.
yes
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-usb
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
