From dd41be2a51bd6823f5d7f5ff7f51ae7c002e7071 Mon Sep 17 00:00:00 2001
From: Alexander Barkov <bar@mariadb.com>
Date: Fri, 1 Nov 2024 12:40:43 +0400
Subject: [PATCH] MDEV-29184 Assertion `0' in Item_row::illegal_method_call,
 Type_handler_row::Item_update_null_value, Item::update_null_value

- Moving the check_cols(1) test from fix_fields() to fix_length_and_dec().
  So the test is now done before the code calling val_decimal()
  in fix_length_and_dec().

- Removing Item_func_interval::fix_fields(), as it become equal
  to the inherited one.
---
 mysql-test/main/func_set.result |  5 +++++
 mysql-test/main/func_set.test   |  8 ++++++++
 sql/item_cmpfunc.cc             | 15 ++++-----------
 sql/item_cmpfunc.h              |  1 -
 4 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/mysql-test/main/func_set.result b/mysql-test/main/func_set.result
index 9dc63220d9e..8fccd0d6374 100644
--- a/mysql-test/main/func_set.result
+++ b/mysql-test/main/func_set.result
@@ -224,3 +224,8 @@ SELECT INTERVAL(1,ROW(1,2));
 ERROR 21000: Operand should contain 1 column(s)
 SELECT INTERVAL(ROW(1,2),1);
 ERROR 21000: Operand should contain 1 column(s)
+#
+# MDEV-29184 Assertion `0' in Item_row::illegal_method_call, Type_handler_row::Item_update_null_value, Item::update_null_value
+#
+SELECT INTERVAL(0, ROW(1,1), 1, 1, 1, 1, 1, 1, 1) AS f;
+ERROR 21000: Operand should contain 1 column(s)
diff --git a/mysql-test/main/func_set.test b/mysql-test/main/func_set.test
index 6df1d8ab97f..13250316a2f 100644
--- a/mysql-test/main/func_set.test
+++ b/mysql-test/main/func_set.test
@@ -147,3 +147,11 @@ SELECT INTERVAL(ROW(1,1),ROW(1,2));
 SELECT INTERVAL(1,ROW(1,2));
 --error ER_OPERAND_COLUMNS
 SELECT INTERVAL(ROW(1,2),1);
+
+
+--echo #
+--echo # MDEV-29184 Assertion `0' in Item_row::illegal_method_call, Type_handler_row::Item_update_null_value, Item::update_null_value
+--echo #
+
+--error ER_OPERAND_COLUMNS
+SELECT INTERVAL(0, ROW(1,1), 1, 1, 1, 1, 1, 1, 1) AS f;
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index 8bc04d07dfd..6ea30e7dde7 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -1951,22 +1951,15 @@ bool Item_func_opt_neg::eq(const Item *item, bool binary_cmp) const
 }
 
 
-bool Item_func_interval::fix_fields(THD *thd, Item **ref)
+bool Item_func_interval::fix_length_and_dec()
 {
-  if (Item_long_func::fix_fields(thd, ref))
-    return true;
-  for (uint i= 0 ; i < row->cols(); i++)
+  uint rows= row->cols();
+
+  for (uint i= 0 ; i < rows; i++)
   {
     if (row->element_index(i)->check_cols(1))
       return true;
   }
-  return false;
-}
-
-
-bool Item_func_interval::fix_length_and_dec()
-{
-  uint rows= row->cols();
   
   use_decimal_comparison= ((row->element_index(0)->result_type() ==
                             DECIMAL_RESULT) ||
diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h
index d680945826d..d651dc3b720 100644
--- a/sql/item_cmpfunc.h
+++ b/sql/item_cmpfunc.h
@@ -1120,7 +1120,6 @@ public:
   Item_func_interval(THD *thd, Item_row *a):
     Item_long_func(thd, a), row(a), intervals(0)
   { }
-  bool fix_fields(THD *, Item **) override;
   longlong val_int() override;
   bool fix_length_and_dec() override;
   LEX_CSTRING func_name_cstring() const override