The "UNKNOWN" means that the SV being stringified was not a valid type - so either its a freed SV, or a corrupted SV. Which means it's either a bug in perl or some XS code, or the OP is doing something which is known to screw up at the Perl level, like modifying an array while iterating over it or using it as function arg.

Dave.

In reply to Re^4: strange error message by dave_the_m
in thread strange error message by esr

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