Change handling of nil value markers in template tables.HEADv2.1

Reported by Bernhard M. Wiedemann. #1348 #1155
Fixes from Peter Cawley, Christian Clason, Lewis Russell.

1 files changed, 5 insertions, 15 deletions

diff --git a/src/lj_parse.c b/src/lj_parse.c
index 70097598..f4116380 100644
--- a/src/lj_parse.c
+++ b/src/lj_parse.c
@@ -1725,7 +1725,7 @@ static void expr_table(LexState *ls, ExpDesc *e)
   FuncState *fs = ls->fs;
   BCLine line = ls->linenumber;
   GCtab *t = NULL;
-  int vcall = 0, needarr = 0, fixt = 0;
+  int vcall = 0, needarr = 0;
   uint32_t narr = 1;  /* First array index. */
   uint32_t nhash = 0;  /* Number of hash entries. */
   BCReg freg = fs->freereg;
@@ -1769,9 +1769,10 @@ static void expr_table(LexState *ls, ExpDesc *e)
       lj_gc_anybarriert(fs->L, t);
       if (expr_isk_nojump(&val)) {  /* Add const key/value to template table. */
         expr_kvalue(fs, v, &val);
-      } else {  /* Otherwise create dummy string key (avoids lj_tab_newkey). */
-        settabV(fs->L, v, t);  /* Preserve key with table itself as value. */
-        fixt = 1;   /* Fix this later, after all resizes. */
+        /* Mark nil value with table value itself to preserve the key. */
+        if (key.k == VKSTR && tvisnil(v)) settabV(fs->L, v, t);
+      } else {  /* Preserve the key for the following non-const store.  */
+        settabV(fs->L, v, t);
         goto nonconst;
       }
     } else {
@@ -1813,17 +1814,6 @@ static void expr_table(LexState *ls, ExpDesc *e)
   } else {
     if (needarr && t->asize < narr)
       lj_tab_reasize(fs->L, t, narr-1);
-    if (fixt) {  /* Fix value for dummy keys in template table. */
-      Node *node = noderef(t->node);
-      uint32_t i, hmask = t->hmask;
-      for (i = 0; i <= hmask; i++) {
-        Node *n = &node[i];
-        if (tvistab(&n->val)) {
-          lj_assertFS(tabV(&n->val) == t, "bad dummy key in template table");
-          setnilV(&n->val);  /* Turn value into nil. */
-        }
-      }
-    }
     lj_gc_check(fs->L);
   }
 }