Derived glyphs have different advance width than their bases.

These may be legitimate, depending on the design but please check.

SourceSerifPro-Black.otf 7 derived glyph(s) have a different advance width than their bases Hbar.sc -11 than H.sc Uhorn.sc -23 than U.sc uni1EE8.sc -23 than U.sc uni1EEA.sc -23 than U.sc uni1EEC.sc -23 than U.sc uni1EEE.sc -23 than U.sc uni1EF0.sc -23 than U.sc

SourceSerifPro-BlackIt.otf 11 derived glyph(s) have a different advance width than their bases uni02C9 (MODIFIER LETTER MACRON) -18 than macron uni040E (CYRILLIC CAPITAL LETTER SHORT U) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) uni0453 (CYRILLIC SMALL LETTER GJE) +12 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +5 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) +1 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +7 than uni0437 (CYRILLIC SMALL LETTER ZE) uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -19 than uni0436 (CYRILLIC SMALL LETTER ZHE) uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) uni2215 (DIVISION SLASH) +285 than fraction uni2219 (BULLET OPERATOR) +240 than periodcentered

SourceSerifPro-Bold.otf 7 derived glyph(s) have a different advance width than their bases Hbar.sc -11 than H.sc Uhorn.sc -23 than U.sc uni1EE8.sc -23 than U.sc uni1EEA.sc -23 than U.sc uni1EEC.sc -23 than U.sc uni1EEE.sc -23 than U.sc uni1EF0.sc -23 than U.sc

SourceSerifPro-BoldIt.otf 13 derived glyph(s) have a different advance width than their bases figuredash -4 than one uni02C9 (MODIFIER LETTER MACRON) -40 than macron uni040E (CYRILLIC CAPITAL LETTER SHORT U) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) uni0453 (CYRILLIC SMALL LETTER GJE) +6 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +11 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -2 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +7 than uni0437 (CYRILLIC SMALL LETTER ZE) uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -14 than uni0436 (CYRILLIC SMALL LETTER ZHE) uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) uni2007 (FIGURE SPACE) -4 than one uni2215 (DIVISION SLASH) +297 than fraction uni2219 (BULLET OPERATOR) +237 than periodcentered

SourceSerifPro-ExtraLight.otf 8 derived glyph(s) have a different advance width than their bases Hbar +1 than H Hbar.sc -13 than H.sc Uhorn.sc -13 than U.sc uni1EE8.sc -13 than U.sc uni1EEA.sc -13 than U.sc uni1EEC.sc -13 than U.sc uni1EEE.sc -13 than U.sc uni1EF0.sc -13 than U.sc

SourceSerifPro-ExtraLightIt.otf 9 derived glyph(s) have a different advance width than their bases figuredash -20 than one uni02C9 (MODIFIER LETTER MACRON) -48 than macron uni0453 (CYRILLIC SMALL LETTER GJE) +10 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +13 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -2 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +6 than uni0437 (CYRILLIC SMALL LETTER ZE) uni2007 (FIGURE SPACE) -13 than one uni2215 (DIVISION SLASH) +265 than fraction uni2219 (BULLET OPERATOR) +240 than periodcentered

SourceSerifPro-It.otf 12 derived glyph(s) have a different advance width than their bases figuredash -13 than one uni02C9 (MODIFIER LETTER MACRON) -96 than macron uni040E (CYRILLIC CAPITAL LETTER SHORT U) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) uni0453 (CYRILLIC SMALL LETTER GJE) -9 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +28 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -12 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +5 than uni0437 (CYRILLIC SMALL LETTER ZE) uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) uni2007 (FIGURE SPACE) -13 than one uni2215 (DIVISION SLASH) +329 than fraction uni2219 (BULLET OPERATOR) +230 than periodcentered

SourceSerifPro-Light.otf 8 derived glyph(s) have a different advance width than their bases Hbar +1 than H Hbar.sc -13 than H.sc Uhorn.sc -18 than U.sc uni1EE8.sc -18 than U.sc uni1EEA.sc -18 than U.sc uni1EEC.sc -18 than U.sc uni1EEE.sc -18 than U.sc uni1EF0.sc -18 than U.sc

SourceSerifPro-LightIt.otf 12 derived glyph(s) have a different advance width than their bases figuredash -17 than one uni02C9 (MODIFIER LETTER MACRON) -68 than macron uni040E (CYRILLIC CAPITAL LETTER SHORT U) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) uni0453 (CYRILLIC SMALL LETTER GJE) +1 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +20 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -7 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +6 than uni0437 (CYRILLIC SMALL LETTER ZE) uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) uni2007 (FIGURE SPACE) -13 than one uni2215 (DIVISION SLASH) +291 than fraction uni2219 (BULLET OPERATOR) +236 than periodcentered

SourceSerifPro-Regular.otf 7 derived glyph(s) have a different advance width than their bases Hbar.sc -12 than H.sc Uhorn.sc -23 than U.sc uni1EE8.sc -23 than U.sc uni1EEA.sc -23 than U.sc uni1EEC.sc -23 than U.sc uni1EEE.sc -23 than U.sc uni1EF0.sc -23 than U.sc

SourceSerifPro-Semibold.otf 7 derived glyph(s) have a different advance width than their bases Hbar.sc -12 than H.sc Uhorn.sc -23 than U.sc uni1EE8.sc -23 than U.sc uni1EEA.sc -23 than U.sc uni1EEC.sc -23 than U.sc uni1EEE.sc -23 than U.sc uni1EF0.sc -23 than U.sc

SourceSerifPro-SemiboldIt.otf 13 derived glyph(s) have a different advance width than their bases figuredash -8 than one uni02C9 (MODIFIER LETTER MACRON) -68 than macron uni040E (CYRILLIC CAPITAL LETTER SHORT U) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) uni0453 (CYRILLIC SMALL LETTER GJE) -2 than uni0433 (CYRILLIC SMALL LETTER GHE) uni045C (CYRILLIC SMALL LETTER KJE) +19 than uni043A (CYRILLIC SMALL LETTER KA) uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -7 than uni0417 (CYRILLIC CAPITAL LETTER ZE) uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +5 than uni0437 (CYRILLIC SMALL LETTER ZE) uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -7 than uni0436 (CYRILLIC SMALL LETTER ZHE) uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) uni2007 (FIGURE SPACE) -8 than one uni2215 (DIVISION SLASH) +313 than fraction uni2219 (BULLET OPERATOR) +233 than periodcentered

Thanks Ernie! Here is my summary:

SourceSerifPro-ExtraLight.otf

8 derived glyph(s) have a different advance width than their bases

Hbar +1 than H ✔
Hbar.sc -13 than H.sc ✔
Uhorn.sc -13 than U.sc ✔
uni1EE8.sc -13 than U.sc ✔
uni1EEA.sc -13 than U.sc ✔
uni1EEC.sc -13 than U.sc ✔
uni1EEE.sc -13 than U.sc ✔
uni1EF0.sc -13 than U.sc ✔

SourceSerifPro-Light.otf

8 derived glyph(s) have a different advance width than their bases

Hbar +1 than H ✔
Hbar.sc -13 than H.sc ✔
Uhorn.sc -18 than U.sc ✔
uni1EE8.sc -18 than U.sc ✔
uni1EEA.sc -18 than U.sc ✔
uni1EEC.sc -18 than U.sc ✔
uni1EEE.sc -18 than U.sc ✔
uni1EF0.sc -18 than U.sc ✔

SourceSerifPro-Regular.otf

7 derived glyph(s) have a different advance width than their bases

Hbar.sc -12 than H.sc ✔
Uhorn.sc -23 than U.sc ✔
uni1EE8.sc -23 than U.sc ✔
uni1EEA.sc -23 than U.sc ✔
uni1EEC.sc -23 than U.sc ✔
uni1EEE.sc -23 than U.sc ✔
uni1EF0.sc -23 than U.sc ✔

SourceSerifPro-Semibold.otf

7 derived glyph(s) have a different advance width than their bases

Hbar.sc -12 than H.sc ✔
Uhorn.sc -23 than U.sc ✔
uni1EE8.sc -23 than U.sc ✔
uni1EEA.sc -23 than U.sc ✔
uni1EEC.sc -23 than U.sc ✔
uni1EEE.sc -23 than U.sc ✔
uni1EF0.sc -23 than U.sc ✔

SourceSerifPro-Bold.otf

7 derived glyph(s) have a different advance width than their bases

Hbar.sc -11 than H.sc ✔
Uhorn.sc -23 than U.sc ✔
uni1EE8.sc -23 than U.sc ✔
uni1EEA.sc -23 than U.sc ✔
uni1EEC.sc -23 than U.sc ✔
uni1EEE.sc -23 than U.sc ✔
uni1EF0.sc -23 than U.sc ✔

SourceSerifPro-Black.otf

7 derived glyph(s) have a different advance width than their bases

Hbar.sc -11 than H.sc ✔
Uhorn.sc -23 than U.sc ✔
uni1EE8.sc -23 than U.sc ✔
uni1EEA.sc -23 than U.sc ✔
uni1EEC.sc -23 than U.sc ✔
uni1EEE.sc -23 than U.sc ✔
uni1EF0.sc -23 than U.sc ✔

Thanks for those finds in the Roman small caps. I assume this has to do with a sidebearing-scaling operation.

SourceSerifPro-ExtraLightIt.otf

9 derived glyph(s) have a different advance width than their bases

figuredash -20 than one ✔
uni02C9 (MODIFIER LETTER MACRON) -48 than macron ✘
Deliberate. IMO modifier letters have a different use than spacing accents. See also here: https://github.com/productiontype/Spectral/issues/13
https://github.com/productiontype/Spectral/issues/14
In fact, I’ll take this opportunity to re-space some of the modifiers in the Roman.
uni0453 (CYRILLIC SMALL LETTER GJE) +10 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +13 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -2 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +6 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni2007 (FIGURE SPACE) -13 than one ✔
uni2215 (DIVISION SLASH) +265 than fraction ✘
Deliberate.
I spaced the division slash so it can be used for a setting like 1∕2, while the fraction slash can be used with numerators and denominators (if a frac feature is really not available)
uni2219 (BULLET OPERATOR) +240 than periodcentered ✔
This was deliberate. I was thinking the bullet operator (mathematical) should have the same width as tabular figures. However I checked other fonts on my system and almost every example ignores this theory, so I unified the bulletoperators with the periodcentereds (and the Romans).

SourceSerifPro-LightIt.otf

12 derived glyph(s) have a different advance width than their bases

figuredash -17 than one ✔
uni02C9 (MODIFIER LETTER MACRON) -68 than macron ✘ (see above)
uni040E (CYRILLIC CAPITAL LETTER SHORT U) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni0453 (CYRILLIC SMALL LETTER GJE) +1 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +20 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -7 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +6 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -14 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni2007 (FIGURE SPACE) -13 than one ✔
uni2215 (DIVISION SLASH) +291 than fraction ✘ (see above)
uni2219 (BULLET OPERATOR) +236 than periodcentered ✔

SourceSerifPro-It.otf

12 derived glyph(s) have a different advance width than their bases

figuredash -13 than one ✔
uni02C9 (MODIFIER LETTER MACRON) -96 than macron ✘ (see above)
uni040E (CYRILLIC CAPITAL LETTER SHORT U) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni0453 (CYRILLIC SMALL LETTER GJE) -9 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +28 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -12 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +5 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -33 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni2007 (FIGURE SPACE) -13 than one ✔
uni2215 (DIVISION SLASH) +329 than fraction ✘ (see above)
uni2219 (BULLET OPERATOR) +230 than periodcentered ✔

SourceSerifPro-SemiboldIt.otf

13 derived glyph(s) have a different advance width than their bases

figuredash -8 than one ✔
uni02C9 (MODIFIER LETTER MACRON) -68 than macron ✘ (see above)
uni040E (CYRILLIC CAPITAL LETTER SHORT U) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni0453 (CYRILLIC SMALL LETTER GJE) -2 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +19 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -7 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +5 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -7 than uni0436 (CYRILLIC SMALL LETTER ZHE) ✔
uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -25 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni2007 (FIGURE SPACE) -8 than one ✔
uni2215 (DIVISION SLASH) +313 than fraction ✘ (see above)
uni2219 (BULLET OPERATOR) +233 than periodcentered ✔

SourceSerifPro-BoldIt.otf

13 derived glyph(s) have a different advance width than their bases

figuredash -4 than one ✔
uni02C9 (MODIFIER LETTER MACRON) -40 than macron ✘ (see above)
uni040E (CYRILLIC CAPITAL LETTER SHORT U) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni0453 (CYRILLIC SMALL LETTER GJE) +6 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +11 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) -2 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +7 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -14 than uni0436 (CYRILLIC SMALL LETTER ZHE) ✔
uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -18 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni2007 (FIGURE SPACE) -4 than one ✔
uni2215 (DIVISION SLASH) +297 than fraction ✘ (see above)
uni2219 (BULLET OPERATOR) +237 than periodcentered ✔

SourceSerifPro-BlackIt.otf

11 derived glyph(s) have a different advance width than their bases

uni02C9 (MODIFIER LETTER MACRON) -18 than macron ✘ (see above)
uni040E (CYRILLIC CAPITAL LETTER SHORT U) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni0453 (CYRILLIC SMALL LETTER GJE) +12 than uni0433 (CYRILLIC SMALL LETTER GHE) ✔
uni045C (CYRILLIC SMALL LETTER KJE) +5 than uni043A (CYRILLIC SMALL LETTER KA) ✔
uni0498 (CYRILLIC CAPITAL LETTER ZE WITH DESCENDER) +1 than uni0417 (CYRILLIC CAPITAL LETTER ZE) ✔
uni0499 (CYRILLIC SMALL LETTER ZE WITH DESCENDER) +7 than uni0437 (CYRILLIC SMALL LETTER ZE) ✔
uni04C2 (CYRILLIC SMALL LETTER ZHE WITH BREVE) -19 than uni0436 (CYRILLIC SMALL LETTER ZHE) ✔
uni04EE (CYRILLIC CAPITAL LETTER U WITH MACRON) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni04F2 (CYRILLIC CAPITAL LETTER U WITH DOUBLE ACUTE) -11 than uni0423 (CYRILLIC CAPITAL LETTER U) ✔
uni2215 (DIVISION SLASH) +285 than fraction ✘ (see above)
uni2219 (BULLET OPERATOR) +240 than periodcentered ✔

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