Re: Problems Building Bluetooth with K6 and CONFIG_REGPARM

[Brian Gerst <bgerst@didntduck.org>]

Horms wrote:
> Hi Andy,
> 
> that does indeed seem to be a problem. I have narrowed it down to
> a combination of using K6 and CONFIG_REGPARM. Hunting around a bit
> I found this http://my.execpc.com/~geezer/osd/gotchas/, which
> suggests the problem is that the asm in question tries to add a register
> to the clobber list which is not available. This makes sense,
> I guess REGPARM is using edx, so inline assembly can't.
> 
> I've CCed the bluetooth maintainers and lkml, hopefully someone there
> will have some input on how to resolve this problem, as inline assembly
> isn't my strong point and the problem seems to manifest in Linus' current
> git tree. 
> 
> The relevant code is the following call to BUILDIO(b,b,char) towards the
> bottom of include/asm/io.h
> 
> BUILDIO is as follows, and I am guessing it is the "Nd"(port) and
> possibley "d"(port) portions that are problematic.

Sounds like a compiler bug, especially since changing the CPU type fixes 
it.  What version of GCC?

--
				Brian Gerst