Merge branch '10.3' into 10.4bb-10.4-MDEV-23468

1 files changed, 17 insertions, 2 deletions

diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index c43dbcaab78..4f878d8437c 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -5473,6 +5473,7 @@ void Item_func_like::print(String *str, enum_query_type query_type)
 longlong Item_func_like::val_int()
 {
   DBUG_ASSERT(fixed == 1);
+  DBUG_ASSERT(escape != -1);
   String* res= args[0]->val_str(&cmp_value1);
   if (args[0]->null_value)
   {
@@ -5559,15 +5560,29 @@ bool fix_escape_item(THD *thd, Item *escape_item, String *tmp_str,
                      bool escape_used_in_parsing, CHARSET_INFO *cmp_cs,
                      int *escape)
 {
-  if (!escape_item->const_during_execution())
+  /*
+    ESCAPE clause accepts only constant arguments and Item_param.
+
+    Subqueries during context_analysis_only might decide they're
+    const_during_execution, but not quite const yet, not evaluate-able.
+    This is fine, as most of context_analysis_only modes will never
+    reach val_int(), so we won't need the value.
+    CONTEXT_ANALYSIS_ONLY_DERIVED being a notable exception here.
+  */
+  if (!escape_item->const_during_execution() ||
+     (!escape_item->const_item() &&
+      !(thd->lex->context_analysis_only & ~CONTEXT_ANALYSIS_ONLY_DERIVED)))
   {
     my_error(ER_WRONG_ARGUMENTS,MYF(0),"ESCAPE");
     return TRUE;
   }
-  
+
+  IF_DBUG(*escape= -1,);
+
   if (escape_item->const_item())
   {
     /* If we are on execution stage */
+    /* XXX is it safe to evaluate is_expensive() items here? */
     String *escape_str= escape_item->val_str(tmp_str);
     if (escape_str)
     {