htmltidy.c example Assertion failed

[StathisKap]

I just copied and pasted the code to an Ubuntu VM using WSL, and when I compile it I get this warning

htmltidy.c: In function ‘dumpNode’:
htmltidy.c:56:9: warning: format not a string literal and no format arguments [-Wformat-security]
   56 |         printf(tidyAttrName(attr));
      |         ^~~~~~

and when I run the binary I get:

./example https://example.com
example: /build/tidy-html5-_lVTuO/tidy-html5-5.6.0/src/config.c:485: prvTidySetOptionInt: Assertion `option_defs[ optId ].type == TidyInteger' failed.
Aborted (core dumped)

(same happens when I comment out the printf that causes the warning)