Bug reports

If you have input that results in a crash or wrong output, then that is a bug.

Step 1: Known bugs

We may already know about this bug. Check here:

Note: Please DO NOT add bug reports directly to the bug tracker. Once an issue has been added to the tracker, feel free to add more information to that report.

Step 2: Creating a bug report

If you have discovered a bug which is not listed, please help us by creating a bug report.

Note: We only accept reports in the form of Tiny examples. We have very limited resources, so any non-minimal example will be rejected. Almost every bug can be demonstrated in four notes or less!

Here is an example of a good bug report:

% Accidentals should be printed for only
% the first note in a tie, but this version
% prints flats on both notes.
\version "2.10.1"

\relative c'' {
 bes1 ~

Step 3: Sending a bug report

Once you have verified that the issue is not already known and created a bug report, please send it to us!

Unfortunately there is no longer an interface for posting to the bug-lilypond list without subscribing; see

for more information.

Step 4: Wait for a response

Once your bug report has been sent to the list, our Bug Squad will examine it; they may ask you for more information. You will be notified when the report will be added to the bug tracker. Please allow up to 4 days, as we have a limited number of volunteers for this task.

Once a bug has been added to the tracker, you can comment it to add more information about it. In order to be automatically notified about any activity on the tracker issue, you may subscribe by clicking the envelope symbol next to the issue title.

Optional help: show the desired behavior

Once an issue has been added to the tracker, it can be very helpful if we can see the desired output. Feel free to add input code and/or images (possibly created with other tools) which demonstrate what you think it should look like!