error: opening HEX file for write: .
# file opened: hex_invalid_filename.asm
1     0000 21               DB "!"
2     0001                  ; `--hex=.` is invalid filename to open for write, at least in Linux
3     0001                  ; let's hope it's invalid on all platforms and this test will work in CI
4     0001
# file closed: hex_invalid_filename.asm

Value    Label
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