[IMPALA-4233] Revisit handling of expr codegen failures

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: Impala 2.8.0
• Component/s: Backend
• Labels: codegen
• Assignee: Michael Ho
• Reporter: Bharath Vissapragada
• Created: 30/Sep/16 21:01
• Updated: 15/May/19 22:45
• Resolved: 15/May/19 22:45

Description

FragmentInstanceState::Open() can fail if codegen of expressions fails:

      // It shouldn't be fatal to fail codegen. However, until IMPALA-4233 is fixed,
      // ScalarFnCall has no fall back to interpretation when codegen fails so propagates
      // the error status for now.
      RETURN_IF_ERROR(runtime_state_->CodegenScalarFns());

In principle many functions can be executed without codegen - after IMPALA-4356 was merged, we always initialise the interpreted path, unless the function requires codegen.

Issue Links

• blocks: IMPALA-4196 Certain builtin functions throw symbol does not exist error when used inside aggregate function
• is related to: IMPALA-4356 Automatically codegen expressions with any root Expr node
• relates to: IMPALA-4432 Cannot execute IR UDF when single node execution is enabled