diff --git a/lisp/international/fontset.el b/lisp/international/fontset.el
index 3deaff9677..533deda61e 100644
--- a/lisp/international/fontset.el
+++ b/lisp/international/fontset.el
@@ -769,7 +769,9 @@ setup-default-fontset
 		      nil 'append))
 
   ;; Special settings for `MATHEMATICAL (U+1D400..U+1D7FF)'.
-  (dolist (math-subgroup '((#x1D400 #x1D433 mathematical-bold)
+  (dolist (math-subgroup '(
+                           ;; First pass: A-z range.
+                           (#x1D400 #x1D433 mathematical-bold)
 			   (#x1D434 #x1D467 mathematical-italic)
 			   (#x1D468 #x1D49B mathematical-bold-italic)
 			   (#x1D49C #x1D4CF mathematical-script)
@@ -782,6 +784,7 @@ setup-default-fontset
 			   (#x1D608 #x1D63B mathematical-sans-serif-italic)
 			   (#x1D63C #x1D66F mathematical-sans-serif-bold-italic)
 			   (#x1D670 #x1D6A3 mathematical-monospace)
+                           ;; Additional passes: dotless, greek, digits, etc.
 			   (#x1D6A4 #x1D6A5 mathematical-italic)
 			   (#x1D6A8 #x1D6E1 mathematical-bold)
 			   (#x1D6E2 #x1D71B mathematical-italic)
@@ -792,13 +795,16 @@ setup-default-fontset
 			   (#x1D7D8 #x1D7E1 mathematical-double-struck)
 			   (#x1D7E2 #x1D7EB mathematical-sans-serif)
 			   (#x1D7EC #x1D7F5 mathematical-sans-serif-bold)
-			   (#x1D7F6 #x1D7FF mathematical-monospace)))
+			   (#x1D7F6 #x1D7FF mathematical-monospace)
+                           ))
     (let ((slot (assq (nth 2 math-subgroup) script-representative-chars)))
       (if slot
-	  (if (vectorp (cdr slot))
-	      (setcdr slot (vconcat (cdr slot) (vector (car math-subgroup))))
-	    (setcdr slot (vector (cadr slot) (car math-subgroup))))
-	(setq slot (list (nth 2 math-subgroup) (car math-subgroup)))
+          (push (car math-subgroup) (cdr slot))
+        ;; First pass: add both CAPITAL A and SMALL A to guard against
+        ;; fonts that only cover capital codepoints.
+	(setq slot (list (nth 2 math-subgroup)
+                         (car math-subgroup)
+                         (+ 26 (car math-subgroup))))
 	(nconc script-representative-chars (list slot))))
     (set-fontset-font
      "fontset-default"