[mythtv] Illegal Instruction - maybe not what you'd think?

[Isaac Richards]

On Thursday 14 November 2002 11:30 pm, Dave Caplinger wrote:
> I just built 0.7; I've successfully built and used versions of MythTV
> since 0.4 all on the same hardware, but now when I build 0.7 I get
> "Illegal Instruction" when I try to run mythtv. (mythfrontend and
> mythepg work fine)
>
> The first thing I thought of was "oh, the settings.pro file must have a
> different architecture in it now" since every single time this comes up
> Isaac says "modify settings.pro to something appropriate for your
> architecture." :-)  However, I compared settings.pro from 0.6 and 0.7
> and they are the same.  It still says -march=pentiumpro, and I still
> have a Celeron 300A(@450MHz), which is a Pentium-II as far as I know,
> that has always worked fine with this setting.
>
> Someplace else on the list I saw mention that this might be somehow
> related to MMX vs MMX2 instructions (a Celeron has MMX but not MMX2, for
> example... but this is the same as a Pentium Pro).  Does this mean that
> someplace in the code it assumes MMX2 support if you have MMX?  If I
> knew how to check this myself I would, sorry. If so, is that a myth bug,
> a QT qmake bug, not a bug at all, etc.?
>
> Just to be perfectly clear: yesterday I was running 0.6 on this box and
> I have changed nothing except to build 0.7.

The deinterlacing has _always_ been MMX2.  It's a bug in that I don't probe 
for it, really.  Maybe the upgrade turned it on, and you had it off before?

Isaac