That's my pleasure. I'll check my codes as you suggest. Thanks very much!
This seems to be a nasty one. How did you get your copy of flexi-streams? It seems that it has been extracted with DOS line endings, and SBCL does not support that. While it will treat the #\Return characters as white space in source code and skip it, it will read it into string literals. In this case, the #\Return ended up in a format string in flexi-streams' length.lisp file and caused an error, as ~#\Return is not a valid format control sequence.
One could debate whether SBCL is buggy here or not, but in any case, you can solve the problem by making sure that your Lisp source files have only
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