1 files changed, 2 insertions, 2 deletions
diff --git a/src/string.c b/src/string.c
index 2b232aa6a..f3f777015 100644
--- a/src/string.c
+++ b/src/string.c
@@ -1128,7 +1128,7 @@ static mrb_value
 mrb_str_downcase_bang(mrb_state *mrb, mrb_value str)
 {
   char *p, *pend;
-  int modify = 0;
+  mrb_bool modify = FALSE;
   struct RString *s = mrb_str_ptr(str);
 
   mrb_str_modify(mrb, s);
@@ -1137,7 +1137,7 @@ mrb_str_downcase_bang(mrb_state *mrb, mrb_value str)
   while (p < pend) {
     if (ISUPPER(*p)) {
       *p = TOLOWER(*p);
-      modify = 1;
+      modify = TRUE;
     }
     p++;
   }