Fix assertion on dereferenced object

Commit 27cc7cd2bc8a accidentally placed the assertion ensuring
that the pointer isn't NULL after it had already been accessed.
Fix by moving the pointer dereferencing to after the assertion.
Backpatch to all supported branches.

Author: Dmitry Koval 
Reviewed-by: Daniel Gustafsson 
Reviewed-by: Michael Paquier 
Discussion: https://postgr.es/m/1618848d-cdc7-414b-9c03-08cf4bef4408@postgrespro.ru
Backpatch-through: 13

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 39d80ccfbada18c2868bb29a28f6d6f4af4dbdeb..963aa39062085339d9cdd7b5120860c04734c2a6 100644 (file)
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -2662,13 +2662,15 @@ bool
 EvalPlanQualFetchRowMark(EPQState *epqstate, Index rti, TupleTableSlot *slot)
 {
    ExecAuxRowMark *earm = epqstate->relsubs_rowmark[rti - 1];
-   ExecRowMark *erm = earm->rowmark;
+   ExecRowMark *erm;
    Datum       datum;
    bool        isNull;
 
    Assert(earm != NULL);
    Assert(epqstate->origslot != NULL);
 
+   erm = earm->rowmark;
+
    if (RowMarkRequiresRowShareLock(erm->markType))
        elog(ERROR, "EvalPlanQual doesn't support locking rowmarks");