Add type cast to pacify warning
@@ -1773,7 +1773,7 @@ mrb_str_reverse_bang(mrb_state *mrb, mrb_value str)
mrb_str_modify(mrb, mrb_str_ptr(str));
len = RSTRING_LEN(str);
- buf = mrb_malloc(mrb, (size_t)len);
+ buf = (char*)mrb_malloc(mrb, (size_t)len);
p = buf;
e = buf + len;
