diff --git a/src/hb-subset-plan.cc b/src/hb-subset-plan.cc
index 00666b8..8f737ca 100644
--- a/src/hb-subset-plan.cc
+++ b/src/hb-subset-plan.cc
@@ -640,7 +640,7 @@
 }
 
 /**
- * hb_subset_plan_unicode_old_glyph_mapping:
+ * hb_subset_plan_unicode_to_old_glyph_mapping:
  * @plan: a subsetting plan.
  *
  * Returns the mapping between codepoints in the original font and the