I don't think its possible (easy) for qx to trigger https://metacpan.org/pod/perldiag#s-x-X-does-not-map-to-Unicode
Why, it's pretty easy 
$ touch $'\xB7'
$ perl -wE 'use open qw( :encoding(utf-8) :std ); qx( ls )'
utf8 "\xB7" does not map to Unicode at -e line 1.

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To the OP:
So, i suppose error appears because of the output that qx operator returns
I suppose the error appears because your file name is not in valid UTF-8. You should check that.

In reply to Re^2: utf8 "\xB7" does not map to Unicode at /usr/local/bin/... line 112. by Anonymous Monk
in thread utf8 "\xB7" does not map to Unicode at /usr/local/bin/бибс/об‰ line 112. by nikolay

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