Re: fix crash with Python 3.11

[Markus Wanner]

On 6/21/22 18:33, Tom Lane wrote:
My inclination at this point is to not back-patch the second change
12d768e70 ("Don't use static storage for SaveTransactionCharacteristics").
It's not clear that the benefit would be worth even a small risk of
somebody being unhappy about the API break.

Actually, the backport of 2e517818f ("Fix SPI's handling of errors") 
already broke the API for code using SPICleanup, as that function had 
been removed. Granted, it's not documented, but still exported.

I propose to re-introduce a no-op placeholder similar to what we have 
for SPI_start_transaction, somewhat like the attached patch.

Regards

Markusdiff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index dd5ef762707..f73c1e79e18 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -422,6 +422,16 @@ SPI_rollback_and_chain(void)
 	_SPI_rollback(true);
 }
 
+/*
+ * SPICleanup is a no-op, kept for backwards compatibility. We rely on
+ * AtEOXact_SPI to cleanup. Extensions should not (need to) fiddle with the
+ * internal SPI state directly.
+ */
+void
+SPICleanup(void)
+{
+}
+
 /*
  * Clean up SPI state at transaction commit or abort.
  */
diff --git a/src/include/executor/spi.h b/src/include/executor/spi.h
index 153eb5c7ad5..1e66a7d2ea0 100644
--- a/src/include/executor/spi.h
+++ b/src/include/executor/spi.h
@@ -205,6 +205,7 @@ extern void SPI_commit_and_chain(void);
 extern void SPI_rollback(void);
 extern void SPI_rollback_and_chain(void);
 
+extern void SPICleanup(void);
 extern void AtEOXact_SPI(bool isCommit);
 extern void AtEOSubXact_SPI(bool isCommit, SubTransactionId mySubid);
 extern bool SPI_inside_nonatomic_context(void);