Merge branch 'master' into v2.1

diff --cc src/Makefile
Simple merge

diff --cc src/lib_string.c
index feaa769741b9a73bd231cf1944f72d1fd7f27f00,9ec6d0c3d187aa51f6c77e61797c81e1aadf9fc9..6ca7a76b6746809aac3971b95d831cf5f725587a
--- 1/src/lib_string.c
--- 2/src/lib_string.c
+++ b/src/lib_string.c
@@@ -62,10 -61,10 +62,10 @@@ LJLIB_ASM(string_byte)             LJLIB_REC(strin
    return FFH_RES(n);
  }
  
 -LJLIB_ASM(string_char)
 +LJLIB_ASM(string_char)                LJLIB_REC(.)
  {
    int i, nargs = (int)(L->top - L->base);
-   char *buf = lj_buf_tmp(L, (size_t)nargs);
 -  char *buf = lj_str_needbuf(L, &G(L)->tmpbuf, (MSize)nargs);
++  char *buf = lj_buf_tmp(L, (MSize)nargs);
    for (i = 1; i <= nargs; i++) {
      int32_t k = lj_lib_checkint(L, i);
      if (!checku8(k))

diff --cc src/lj_record.c
Simple merge