1 files changed, 1 insertions, 1 deletions

diff --git a/src/lib_string.c b/src/lib_string.c
index 36fd3f53f..69b29356a 100644
--- a/src/lib_string.c
+++ b/src/lib_string.c
@@ -873,7 +873,7 @@ LJLIB_CF(string_format)
         if (LJ_UNLIKELY((tv.u32.hi << 1) >= 0xffe00000)) {
           /* Canonicalize output of non-finite values. */
           char *p, nbuf[LJ_STR_NUMBUF];
-          size_t len = lj_str_bufnum(nbuf, &tv);
+          MSize len = lj_str_bufnum(nbuf, &tv);
           if (strfrmt[-1] < 'a') {
             nbuf[len-3] = nbuf[len-3] - 0x20;
             nbuf[len-2] = nbuf[len-2] - 0x20;