Glyphs in the GDEF mark class must be non-spacing.

[glenda-tn]

The following non-mark characters (spacing marks) should not be in the GDEF mark glyph class:

• U+0384
• U+0385
• U+1FBD
• U+1FBF
• U+1FC0
• U+1FC1
• U+1FCD
• U+1FCE
• U+1FCF
• U+1FDD
• U+1FDE
• U+1FDF
• U+1FED
• U+1FEE
• U+1FEF
• U+1FFD
• U+1FFE

The above code points are all defined as spacing marks in Unicode. To use as non-spacing marks, create a duplicate component set on zero width.

[guidoferreyra]

All the anchors were removed from the listed glyph so it will be not longer added to GDEF. I still need to remove the anchor from /tonos.cap but I don’t want to overwrite any changes being made now.

[djrrb]

feel free to make change, i can dive in tomorrow morning

[guidoferreyra]

Done 4c27e63

[glenda-tn]

⚠️ WARN The following spacing glyphs may be in the GDEF mark glyph class by mistake:

• [ ] acute_greek.sc (unencoded)
• [ ] dieresistonos (U+0385)
• [ ] grave_greek.sc (unencoded)
• [ ] tonos.sc (unencoded)
• [ ] uni1FBE (U+1FBE)
• [ ] uni1FBF (U+1FBF)
• [ ] uni1FBF.sc (unencoded)
• [ ] uni1FC0 (U+1FC0)
• [ ] uni1FC1 (U+1FC1)
• [ ] uni1FCD (U+1FCD)
• [ ] uni1FCD.sc (unencoded)
• [ ] uni1FCE (U+1FCE)
• [ ] uni1FCE.sc (unencoded)
• [ ] uni1FCF (U+1FCF)
• [ ] uni1FCF.sc (unencoded)
• [ ] uni1FDD (U+1FDD)
• [ ] uni1FDD.sc (unencoded)
• [ ] uni1FDE (U+1FDE)
• [ ] uni1FDE.sc (unencoded)
• [ ] uni1FDF (U+1FDF)
• [ ] uni1FDF.sc (unencoded)
• [ ] uni1FED (U+1FED)
• [ ] uni1FEF (U+1FEF)
• [ ] uni1FFD (U+1FFD)
• [ ] uni1FFE (U+1FFE)
• [ ] uni1FFE.sc (unencoded)
• [ ]

[glenda-tn]

These have reappeared: 🔥 FAIL The following non-mark characters should not be in the GDEF mark glyph class:

• [ ] U+0384
• [ ] U+0385
• [ ] U+1FBE
• [ ] U+1FBF
• [ ] U+1FC0
• [ ] U+1FC1
• [ ] U+1FCD
• [ ] U+1FCE
• [ ] U+1FCF
• [ ] U+1FDD
• [ ] U+1FDE
• [ ] U+1FDF
• [ ] U+1FED
• [ ] U+1FEF
• [ ] U+1FFD
• [ ] U+1FFE

[djrrb]

@guidoferreyra could you perhaps help me with this? I thought these could be spaced and have anchors, and would be set to zero width on build? sorry for the confusion.

[guidoferreyra]

The glyph list posted by Glenda are polytonic greek diacritics which are not considered non-spacing and should not be on the GDEF mark class. To prevent fontmake to add it to the GDEF is needed to remove the anchors from it which might not be possible if the anchors are being used to align diacriticis on composite glyphs.

[glenda-tn]

A solution is to add duplicate glyph components, unencoded, and classify the duplicate as a mark. Note the dupe would be on zero width while the encoded glyph remains spacing. The substitution takes place in `ccmp' very early in processing. I used this solution many times in the past.

[glenda-tn]

From Unicode 15, Chapter 7

[djrrb]

Following up on this: Adding duplicates as suggested above increases the complexity of the font, and we are hesitant to do something that creates mores issues than it solves. Since this is a fontbakery WARN and not a FAIL, we will let this stand unless otherwise requested.