diff --git a/spec/compiler/rules/character_set_spec.cc b/spec/compiler/rules/character_set_spec.cc
index eb17f78b..551779a5 100644
--- a/spec/compiler/rules/character_set_spec.cc
+++ b/spec/compiler/rules/character_set_spec.cc
@@ -108,6 +108,12 @@ describe("character sets", []() {
             CharacterSet set2({ {'c', 'y'} });
             AssertThat(set1.intersect(set2), Equals(CharacterSet({ {'c', 'e'}, {'w', 'y'} })));
         });
+
+        it("works for some sets", []() {
+            CharacterSet set1({ {'i', 'i'} });
+            CharacterSet set2({ {'a', 'z'} });
+            AssertThat(set1.intersect(set2), Equals(CharacterSet({ {'i', 'i'} })));
+        });
     });
 });
 
diff --git a/src/compiler/rules/character_set.cc b/src/compiler/rules/character_set.cc
index 888762b5..f8fe2afe 100644
--- a/src/compiler/rules/character_set.cc
+++ b/src/compiler/rules/character_set.cc
@@ -111,6 +111,8 @@ namespace tree_sitter  {
                     } else if (new_max <= max_int(range)) {
                         new_ranges.insert(CharacterRange(new_max + 1, range.max));
                         add_range(&removed_set, CharacterRange(range.min, new_max));
+                    } else {
+                        add_range(&removed_set, range);
                     }
                 } else if (new_min <= max_int(range)) {
                     if (new_max < max_int(range)) {