diff --git a/libaegisub/common/character_count.cpp b/libaegisub/common/character_count.cpp
index 285ae1433..07ebf5fcc 100644
--- a/libaegisub/common/character_count.cpp
+++ b/libaegisub/common/character_count.cpp
@@ -84,9 +84,9 @@ int ignore_mask_to_icu_mask(int mask) {
 }
 
 namespace agi {
-size_t CharacterCount(std::string::const_iterator begin, std::string::const_iterator end, int mask) {
-	mask = ignore_mask_to_icu_mask(mask);
-	if ((mask & agi::IGNORE_BLOCKS) == 0)
+size_t CharacterCount(std::string::const_iterator begin, std::string::const_iterator end, int ignore) {
+	int mask = ignore_mask_to_icu_mask(ignore);
+	if ((ignore & agi::IGNORE_BLOCKS) == 0)
 		return count_in_range(begin, end, mask);
 
 	size_t characters = 0;