Sometimes, you will find a build error on a Yocto recipe that you have not modified. The first place to check for errors is the community itself, but before launching your mail client, head to http://errors.yoctoproject.org. The welcome page is displayed as follows:

This is a central database of mostly autobuilder, but also user-reported, errors. Here, you may check whether someone else is experiencing the same problem.

You can submit your own build failure to the database to help the community debug the problem. To do so, you may use the report-error class. Add the following to your conf/local.conf file:

INHERIT += "report-error"  

By default, the error information is stored under tmp/log/error-report under the build directory, but you can set a specific location with the ERR_REPORT_DIR variable.

When the error reporting tool is activated, a build error will be captured in a file in the error-report folder. The build output will also print a command to send the error log to the server:

$ send-error-report ${LOG_DIR}/error-report/error-report_${TSTAMP}  

When this command is executed, it will report back with a link to the upstream error.

You can set up a local error server, and use that instead by passing a server argument. The error server code is a Django web application and setting up details can be found at http://git.yoctoproject.org/cgit/cgit.cgi/error-report-web/tree/README.