SBCL uses Launchpad to track bugs. The bug database is available at: https://bugs.launchpad.net/sbcl Reporting bugs there requires registering at Launchpad. However, bugs can also be reported on the mailing list sbcl-bugs, which is moderated but does _not_ require subscribing. Simply send email to sbcl-bugs@lists.sourceforge.net and the bug will be checked and added to Launchpad by SBCL maintainers. Historical note: before Launchpad was adopted this file contained a list of currently open bugs. If you run into an SBCL bug number in the range 1-431 inclusive, it refers to that list. Refer to User Manual for more details.