https://bugs.winehq.org/show_bug.cgi?id=39334
--- Comment #1 from Nikolay Sivov bunglehead@gmail.com --- The issue seems to be about large usWinDescent value, section of OS/2 table:
--- 'OS/2' version: 2 ... fsSelection: 0x0040 ... sTypoAscender: 900 sTypoDescender: -263 ... usWinAscent: 900 usWinDescent: 65273 ---
Later this part:
--- ppem = MulDiv(ft_face->units_per_EM, height, pOS2->usWinAscent + pOS2->usWinDescent); ---
produces 0, because unitsPerEm is 1000 for this font, so for not large enough height result will be always zero.
Similar thing happens on MacOS (with different font), as current test page shows.