Comment # 51 on bug 1005673 from Stanislav Brabec

Here is the SANE bisecting HOWTO:

Do it once on start:

git clone git://anonscm.debian.org/git/sane/sane-backends.git
cd sane-backends
./configure
make -j7 # ~ the number of cores minus 1

If you have everything compiler needs, you compiled a head version.

Then you can start to bisect:

git bisect start

# Now copy built libraries to your system and test.
git bisect bad # You have HEAD, guessing that this will be bad

# Normally you don't need this, but some versions of SANE build have a bug, it
# re-generates po files each time. Reset them.
git reset --hard
git checkout d353a1c5f2f1420657654b0eae1d063e8cb82703 # This is 1.0.23
make -j7 # ~ the number of cores minus 1
# Now copy built libraries to your system and test.
git bisect good # Guessing that this is good


Now git suggest you one of changes between those two and you should test it:

# Normally you don't need this, but some versions of SANE build have a bug, it
# re-generates po files each time. Reset them.
git reset --hard
make -j7 # ~ the number of cores minus 1
# Now copy built libraries to your system and test.

# And now answer one of following:
git bisect good # Tested, good
git bisect bad # Tested, bad
git bisect skip # Does not compile, cannot be tested

# And now iterate until you get the breaking change. It should be done in about
9 steps.

If no mistake was done, you will get a change that breaks it.


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can be interesting for others, feel free use Bugzilla.