Slime spat this out at me:
Warning (slime): "ele-bdb.asd":46:33 (pt=1463). Caught error during fontification while searching for forms that are suppressed by reader-conditionals. The error was: (cl-assertion-failed (<= (point) limit)).
This is a bug in Slime itself. Please report this to the mailinglist slime-devel@common-lisp.net and include your Emacs version, the guilty Lisp source file, the header of this message, and the following backtrace.
Backtrace: backtrace() slime-bug("Caught error during fontification while searching for forms that are suppressed by reader-conditionals. The error was: %S." (cl-assertion-failed (<= (point) limit))) byte-code("\302\303\304 "\207" [result condition nil slime-bug "Caught error during fontification while searching for forms that are suppressed by reader-conditionals. The error was: %S."] 3) slime-search-suppressed-forms(1101) font-lock-fontify-keywords-region(534 1101 nil) font-lock-default-fontify-region(534 1101 nil) font-lock-fontify-region(534 1101) run-hook-with-args(font-lock-fontify-region 534 1101) byte-code("\302\303 #\207" [start next run-hook-with-args jit-lock-functions] 4) jit-lock-fontify-now(534 1034) jit-lock-function(534)
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So I'm dutifully following its instructions, and including this file:
Hope this helps.