Fix overly-strict sanity check in BeginInternalSubTransaction that made it

fail when used in a deferred trigger.  Bug goes back to 8.0; no doubt the
reason it hadn't been noticed is that we've been discouraging use of
user-defined constraint triggers.  Per report from Frank van Vugt.

diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 016b28974d8062f12855ff723f56843d25448cac..c448bcaa2072f3be5d0a144998115a6a1acc83a3 100644 (file)
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -2935,9 +2935,10 @@ RollbackToSavepoint(List *options)
 /*
  * BeginInternalSubTransaction
  *             This is the same as DefineSavepoint except it allows TBLOCK_STARTED
- *             state, and therefore it can safely be used in a function that might
- *             be called when not inside a BEGIN block.  Also, we automatically
- *             cycle through CommitTransactionCommand/StartTransactionCommand
+ *             and TBLOCK_END states, and therefore it can safely be
+ *             used in functions that might be called when not inside a BEGIN block
+ *             or when running deferred triggers at COMMIT time.  Also, it
+ *             automatically does CommitTransactionCommand/StartTransactionCommand
  *             instead of expecting the caller to do it.
  */
 void
@@ -2949,6 +2950,7 @@ BeginInternalSubTransaction(char *name)
        {
                case TBLOCK_STARTED:
                case TBLOCK_INPROGRESS:
+               case TBLOCK_END:
                case TBLOCK_SUBINPROGRESS:
                        /* Normal subtransaction start */
                        PushTransaction();
@@ -2966,7 +2968,6 @@ BeginInternalSubTransaction(char *name)
                case TBLOCK_DEFAULT:
                case TBLOCK_BEGIN:
                case TBLOCK_SUBBEGIN:
-               case TBLOCK_END:
                case TBLOCK_SUBEND:
                case TBLOCK_ABORT:
                case TBLOCK_SUBABORT: