[Gimp-developer] Two questions about updating GIMP from git

[Elle Stone <ellestone ninedegreesbelow com>]

I update three separate copies of babl/gegl/gimp from git, each in a 
prefix, on average once a week.
Other than reading the git logs, is there an easy way to check to see 
whether software requirements (png, tiff, glib, etc) have been bumped up?
Also, I've been updating command by command in a virtual terminal and my 
computer isn't very fast. I'd like to write a script that executes all 
the commands all at once, but exits with an informative error message 
printed to screen as soon as something doesn't configure, compile, or 
install properly. Does anyone have such a script or know how to write one?
Elle