More a note than anything else. COPT crashes when it encounters non-ascii characters. This was found while compiling a program containing Cyrllic text with sdcc. Both compilers (sdcc and sccz80) convert non-ascii characters into DEFB lists before COPT would normally see such text but sdcc also inserts commented out C code into its output. If that C code contains Cyrillic text, COPT crashes and the compile fails.
What I did was add "--no-c-code-in-asm" for sdcc's invocation.
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