[PATCH] serial: DCC(JTAG) serial and console emulation support

Nicolas Pitre nico at fluxnic.net
Wed Oct 6 12:22:21 EDT 2010

On Wed, 6 Oct 2010, Daniel Walker wrote:

> On Wed, 2010-10-06 at 11:47 -0400, Nicolas Pitre wrote:
> > It is the wrong fix nevertheless.  And in this case it isn't a question 
> > of opinion.
> I'm not saying your wrong, I'm sure you know more about it than I do. I
> was just letting you know why I added it .

Sure.  However it is best to _understand_ why such things may apparently 
fix things.  In this case it would have been by accident, and the code 
could be broken again with a different gcc version.

Adding "cc" in the clobber list is needed only when the asm code is 
modifying the condition flags.

I'd suggest you look at the disassembly difference with and without it. 
My guess is that the whole thing gets optimized away as there is no 
dependencies to be dependent on, in which case the proper fix would be 
to mark it with "volatile".


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