diff --git a/source/mijin/util/string.hpp b/source/mijin/util/string.hpp
index d6448e6..8ba7e40 100644
--- a/source/mijin/util/string.hpp
+++ b/source/mijin/util/string.hpp
@@ -530,7 +530,7 @@ ConvertCharTypeResult convertCharType(const TFrom* chrFrom, std::size_t numFrom,
             if (numTo < MB_CUR_MAX)
             {
                 char tmpBuf[MB_LEN_MAX];
-                const ConvertCharTypeResult result = convertCharType(chrFrom, tmpBuf, mbstate);
+                const ConvertCharTypeResult result = convertCharType(chrFrom, numFrom, tmpBuf, MB_LEN_MAX, mbstate);
                 if (result && result.numWritten <= numTo)
                 {
                     std::memcpy(outTo, tmpBuf, result.numWritten);