About the C code: you're talking about C code that tries to interpret the invalid utf-8, right?

Yes. I was specifically (but implicitly) referring to XS code, C code catered for Perl interaction. The UTF8 flag is interpreted as a promise that the buffer will be valid UTF8. Of course, it would be better to use Perl's macros for UTF8 handling, but that doesn't work if you're calling a library function that doesn't do SVs but does require valid UTF-8.

about the (removed) line: "Another possibility is careless use of utf8::upgrade()." That's removed because utf8::upgrade() is always safe (if you start out with valid utf-8 flags), right?

Exactly. The original author probably confused utf8::upgrade with Encode::_utf8_on.

Juerd # { site => 'juerd.nl', do_not_use => 'spamtrap', perl6_server => 'feather' }

In reply to Re^6: A UTF8 round trip with MySQL by Juerd
in thread A UTF8 round trip with MySQL by clinton

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