"Compiling ufo failed" Error when generating a static font

[vv-monsalve]

This error was reported when generating a static font. I never had it before so I don't know what it means:

fontmake.errors.FontmakeError: In 'Festive-Pro.glyphs' -> 'master_ufo/FestivePro-Regular.designspace' -> 'master_ufo/instance_ufo/FestivePro-Regular.ufo': Compiling UFO failed: not enough values to unpack (expected 4, got 2)

Glyphs file: https://github.com/googlefonts/festive/blob/master/sources/Festive-Pro.glyphs

Command used: gftools builder config.yml and this one to verify it fontmake -g Festive-Pro.glyphs -i -o ttf

[RosaWagner]

It reminds me of an error I got… Are there bracket tricks in the sources?

[moyogo]

It looks like ufo2ft's RemoveOverlapsFilter doesn't catch the error raised by the overlap removing backend, booleanOperations or pathops, with the glyph H.5.

I opened googlefonts/ufo2ft#492.

This seems to be the issue:

[moyogo]

Only H.5 and c.7 seem to have the issue.

[vv-monsalve]

It reminds me of an error I got… Are there bracket tricks in the sources?

Nop, no bracket tricks found

[vv-monsalve]

@moyogo Thanks!. I'll check on that