CodeQL: Potentially uninitialized local variable
CodeQL: Potentially uninitialized local variable

This is not really uninitialized, it would only happen if the string
dumped with dump_string was empty of contained invalid UTF-8. Setting
an initial value has no effect since codepoint is used as an "out"
value in utf8_iterate.

nicolasff/webdis,nicolasff/webdis,nicolasff/webdis,nicolasff/webdis,nicolasff/webdis