diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc
index fd9095ea659..6993bb4183c 100644
--- a/sql/sql_trigger.cc
+++ b/sql/sql_trigger.cc
@@ -396,7 +396,9 @@ bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create)
   bool result= TRUE;
   String stmt_query;
   bool lock_upgrade_done= FALSE;
+  bool backup_of_table_list_done= 0;;
   MDL_ticket *mdl_ticket= NULL;
+  MDL_request mdl_request_for_trn;
   Query_tables_list backup;
   DBUG_ENTER("mysql_create_or_drop_trigger");
 
@@ -446,6 +448,16 @@ bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create)
     DBUG_RETURN(TRUE);
   }
 
+  /* Protect against concurrent create/drop */
+  MDL_REQUEST_INIT(&mdl_request_for_trn, MDL_key::TABLE,
+                   create ? tables->db.str : thd->lex->spname->m_db.str,
+                   thd->lex->spname->m_name.str,
+                   MDL_EXCLUSIVE, MDL_EXPLICIT);
+  if (thd->mdl_context.acquire_lock(&mdl_request_for_trn,
+                                    thd->variables.lock_wait_timeout))
+    goto end;
+
+
   if (!create)
   {
     bool if_exists= thd->lex->if_exists();
@@ -454,6 +466,7 @@ bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create)
       Protect the query table list from the temporary and potentially
       destructive changes necessary to open the trigger's table.
     */
+    backup_of_table_list_done= 1;
     thd->lex->reset_n_backup_query_tables_list(&backup);
     /*
       Restore Query_tables_list::sql_command, which was
@@ -623,7 +636,7 @@ end:
     mdl_ticket->downgrade_lock(MDL_SHARED_NO_READ_WRITE);
 
   /* Restore the query table list. Used only for drop trigger. */
-  if (!create)
+  if (backup_of_table_list_done)
     thd->lex->restore_backup_query_tables_list(&backup);
 
   if (!result)
@@ -635,6 +648,9 @@ end:
                   thd->lex->spname->m_name.str, static_cast<uint>(thd->lex->spname->m_name.length));
   }
 
+  if (mdl_request_for_trn.ticket)
+    thd->mdl_context.release_lock(mdl_request_for_trn.ticket);
+
   DBUG_RETURN(result);
 #ifdef WITH_WSREP
 wsrep_error_label:
diff --git a/strings/decimal.c b/strings/decimal.c
index 16bc887814a..1f9a28c1ad5 100644
--- a/strings/decimal.c
+++ b/strings/decimal.c
@@ -2619,7 +2619,8 @@ void test_d2f(const char *s, int ex)
 
 void test_d2b2d(const char *str, int p, int s, const char *orig, int ex)
 {
-  char s1[100], buf[100], *end;
+  char s1[100], *end;
+  uchar buf[100];
   int res, i, size=decimal_bin_size(p, s);
 
   sprintf(s1, "'%s'", str);
@@ -2937,27 +2938,27 @@ int main()
   test_f2d(1234500009876.5, 0);
 
   printf("==== ulonglong2decimal ====\n");
-  test_ull2d(ULL(12345), "12345", 0);
-  test_ull2d(ULL(0), "0", 0);
-  test_ull2d(ULL(18446744073709551615), "18446744073709551615", 0);
+  test_ull2d(12345ULL, "12345", 0);
+  test_ull2d(0ULL, "0", 0);
+  test_ull2d(18446744073709551615ULL, "18446744073709551615", 0);
 
   printf("==== decimal2ulonglong ====\n");
   test_d2ull("12345", "12345", 0);
   test_d2ull("0", "0", 0);
   test_d2ull("18446744073709551615", "18446744073709551615", 0);
-  test_d2ull("18446744073709551616", "18446744073", 2);
+  test_d2ull("18446744073709551616", "18446744073709551615", 2);
   test_d2ull("-1", "0", 2);
   test_d2ull("1.23", "1", 1);
-  test_d2ull("9999999999999999999999999.000", "9999999999999999", 2);
+  test_d2ull("9999999999999999999999999.000", "18446744073709551615", 2);
 
   printf("==== longlong2decimal ====\n");
-  test_ll2d(LL(-12345), "-12345", 0);
-  test_ll2d(LL(-1), "-1", 0);
-  test_ll2d(LL(-9223372036854775807), "-9223372036854775807", 0);
-  test_ll2d(ULL(9223372036854775808), "-9223372036854775808", 0);
+  test_ll2d(-12345LL, "-12345", 0);
+  test_ll2d(-1LL, "-1", 0);
+  test_ll2d(-9223372036854775807LL, "-9223372036854775807", 0);
+  test_ll2d(9223372036854775808ULL, "-9223372036854775808", 0);
 
   printf("==== decimal2longlong ====\n");
-  test_d2ll("18446744073709551615", "18446744073", 2);
+  test_d2ll("18446744073709551615", "9223372036854775807", 2);
   test_d2ll("-1", "-1", 0);
   test_d2ll("-1.23", "-1", 1);
   test_d2ll("-9223372036854775807", "-9223372036854775807", 0);
@@ -3131,12 +3132,12 @@ int main()
 
   printf("==== decimal2string ====\n");
   test_pr("123.123", 0, 0, 0, "123.123", 0);
-  test_pr("123.123", 7, 3, '0', "123.123", 0);
-  test_pr("123.123", 9, 3, '0', "00123.123", 0);
-  test_pr("123.123", 9, 4, '0', "0123.1230", 0);
-  test_pr("123.123", 9, 5, '0', "123.12300", 0);
-  test_pr("123.123", 9, 2, '0', "000123.12", 1);
-  test_pr("123.123", 9, 6, '0', "23.123000", 2);
+  test_pr("123.123", 7, 3, '0', "0123.123", 0);
+  test_pr("123.123", 9, 3, '0', "000123.123", 0);
+  test_pr("123.123", 9, 4, '0', "00123.1230", 0);
+  test_pr("123.123", 9, 5, '0', "0123.12300", 0);
+  test_pr("123.123", 9, 2, '0', "0000123.12", 1);
+  test_pr("123.123", 8, 6, '0', "23.123000", 2);
 
   printf("==== decimal_shift ====\n");
   test_sh("123.123", 1, "1231.23", 0);