[yocto] Is the build system SCM sensitive?

[Gary Thomas]

I had a complete build (details probably don't matter) using
Poky master.  I'm working on a fix to one of the core recipes,
so I made a local branch:
   % git checkout -b fix-python-pygtk master
I made a single line change in the recipe (removing a line from
the do_install step).  When I then rebuilt the recipe, to my
surprise, there were more than 450 tasks (73 unique recipes)
executed :-(

How does this make any sense?  unless the build system cares
that I changed the branch?

n.b. I'm happy to provide more details if necessary.  Also, I
did this twice in two different build trees and saw the same
strangeness.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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