Sometimes I wonder, is it me or is it IT ?
Today, without the u8 prefix on the quoted string literal, the code below does execute as expected when compiled with Pelles C and with the console codepage set to 65001 and with a console font containing Greek alphabet glyphs.
#include<stdio.h>
int main(void) {
printf("%s", "δυσκατανοήτων");
return 0;
}