Bug #29156 events crash server in test suite

don't free thd->lex->sphead if we didn't do lex_start(),
as we can have garbage there


mysql-test/r/events_bugs.result:
  Bug #29156 events crash server in test suite
  
  test result added
mysql-test/t/events_bugs.test:
  Bug #29156 events crash server in test suite
  
  testcase

1 files changed, 10 insertions, 8 deletions

diff --git a/sql/event_data_objects.cc b/sql/event_data_objects.cc
index 77dc33e6265..5aca40d357a 100644
--- a/sql/event_data_objects.cc
+++ b/sql/event_data_objects.cc
@@ -1778,7 +1778,7 @@ Event_job_data::execute(THD *thd, bool drop)
                     "[%s].[%s.%s] execution failed, "
                     "failed to authenticate the user.",
                     definer.str, dbname.str, name.str);
-    goto end;
+    goto end_no_lex_start;
   }
 #endif
 
@@ -1795,11 +1795,11 @@ Event_job_data::execute(THD *thd, bool drop)
                     "[%s].[%s.%s] execution failed, "
                     "user no longer has EVENT privilege.",
                     definer.str, dbname.str, name.str);
-    goto end;
+    goto end_no_lex_start;
   }
 
   if (construct_sp_sql(thd, &sp_sql))
-    goto end;
+    goto end_no_lex_start;
 
   /*
     Set up global thread attributes to reflect the properties of
@@ -1860,6 +1860,13 @@ Event_job_data::execute(THD *thd, bool drop)
   }
 
 end:
+  if (thd->lex->sphead)                        /* NULL only if a parse error */
+  {
+    delete thd->lex->sphead;
+    thd->lex->sphead= NULL;
+  }
+
+end_no_lex_start:
   if (drop && !thd->is_fatal_error)
   {
     /*
@@ -1887,11 +1894,6 @@ end:
         ret= 1;
     }
   }
-  if (thd->lex->sphead)                        /* NULL only if a parse error */
-  {
-    delete thd->lex->sphead;
-    thd->lex->sphead= NULL;
-  }
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   if (save_sctx)
     event_sctx.restore_security_context(thd, save_sctx);