1 files changed, 18 insertions, 4 deletions

diff --git a/src/lib_string.c b/src/lib_string.c
index 29bcb8fe..255689ce 100644
--- a/src/lib_string.c
+++ b/src/lib_string.c
@@ -122,11 +122,25 @@ static int writer_buf(lua_State *L, const void *p, size_t size, void *sb)
 
 LJLIB_CF(string_dump)
 {
-  GCfunc *fn = lj_lib_checkfunc(L, 1);
-  int strip = L->base+1 < L->top && tvistruecond(L->base+1);
-  SBuf *sb = lj_buf_tmp_(L);  /* Assumes lj_bcwrite() doesn't use tmpbuf. */
+  GCproto *pt = lj_lib_checkLproto(L, 1, 1);
+  uint32_t flags = 0;
+  SBuf *sb;
+  TValue *o = L->base+1;
+  if (o < L->top) {
+    if (tvisstr(o)) {
+      const char *mode = strVdata(o);
+      char c;
+      while ((c = *mode++)) {
+        if (c == 's') flags |= BCDUMP_F_STRIP;
+        if (c == 'd') flags |= BCDUMP_F_DETERMINISTIC;
+      }
+    } else if (tvistruecond(o)) {
+      flags |= BCDUMP_F_STRIP;
+    }
+  }
+  sb = lj_buf_tmp_(L);  /* Assumes lj_bcwrite() doesn't use tmpbuf. */
   L->top = L->base+1;
-  if (!isluafunc(fn) || lj_bcwrite(L, funcproto(fn), writer_buf, sb, strip))
+  if (!pt || lj_bcwrite(L, pt, writer_buf, sb, flags))
     lj_err_caller(L, LJ_ERR_STRDUMP);
   setstrV(L, L->top-1, lj_buf_str(L, sb));
   lj_gc_check(L);