diff --git a/aegisub/universalchardet/JpCntx.h b/aegisub/universalchardet/JpCntx.h
index 734b8f058..0b13ecb0a 100644
--- a/aegisub/universalchardet/JpCntx.h
+++ b/aegisub/universalchardet/JpCntx.h
@@ -46,7 +46,7 @@
 #define MAX_REL_THRESHOLD     1000
 
 //hiragana frequency category table
-extern char jp2CharContext[83][83];
+extern const char jp2CharContext[83][83];
 
 class JapaneseContextAnalysis
 {