Fix ABI break by moving PROCSIG_SLOTSYNC_MESSAGE in ProcSignalReason

Commit 15910b1c363 PROCSIG_SLOTSYNC_MESSAGE in the middle of
enum ProcSignalReason, breaking the ABI.

Fix this by moving PROCSIG_SLOTSYNC_MESSAGE to just before the last entry,
NUM_PROCSIGNALS, to restore ordering of other entries.

This increases the value of NUM_PROCSIGNALS, which technically changes the ABI.
However, since it represents the number of enum entries (not a signal reason),
and no affected third-party code is known, this change will be recorded in
.abi-compliance-history later.

Per buildfarm member crake.

Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Discussion: https://postgr.es/m/CAHGQGwH_AAbtsiYDJt65N7_4PJ0CgOJmBEaCq68e5_tcuG_vXw@mail.gmail.com
Backpatch-through: 17 only

diff --git a/src/include/storage/procsignal.h b/src/include/storage/procsignal.h
index 126c44bcf1d742bddb1fa2c782f7558b46cca618..58a042f1b9f1b484d246ea933e7ac520990c4f11 100644 (file)
--- a/src/include/storage/procsignal.h
+++ b/src/include/storage/procsignal.h
@@ -36,7 +36,6 @@ typedef enum
        PROCSIG_BARRIER,                        /* global barrier interrupt  */
        PROCSIG_LOG_MEMORY_CONTEXT, /* ask backend to log the memory contexts */
        PROCSIG_PARALLEL_APPLY_MESSAGE, /* Message from parallel apply workers */
-       PROCSIG_SLOTSYNC_MESSAGE,       /* ask slot synchronization to stop */
 
        /* Recovery conflict reasons */
        PROCSIG_RECOVERY_CONFLICT_FIRST,
@@ -49,6 +48,8 @@ typedef enum
        PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK,
        PROCSIG_RECOVERY_CONFLICT_LAST = PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK,
 
+       PROCSIG_SLOTSYNC_MESSAGE,       /* ask slot synchronization to stop */
+
        NUM_PROCSIGNALS                         /* Must be last! */
 } ProcSignalReason;