commit 689869c791aa7d13f408430ef438291bddb84b2f
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date:   Thu Feb 13 12:31:37 2014 -0300

    9.3 tweaks to avoid ABI break

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 534a9ea..6daa14a 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -1170,11 +1170,11 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		{"autovacuum_freeze_table_age", RELOPT_TYPE_INT,
 		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, freeze_table_age)},
 		{"autovacuum_multixact_freeze_min_age", RELOPT_TYPE_INT,
-		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, multixact_freeze_min_age)},
+		offsetof(StdRdOptions, autovacuum2) +offsetof(AutoVacOpts2, multixact_freeze_min_age)},
 		{"autovacuum_multixact_freeze_max_age", RELOPT_TYPE_INT,
-		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, multixact_freeze_max_age)},
+		offsetof(StdRdOptions, autovacuum2) +offsetof(AutoVacOpts2, multixact_freeze_max_age)},
 		{"autovacuum_multixact_freeze_table_age", RELOPT_TYPE_INT,
-		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, multixact_freeze_table_age)},
+		offsetof(StdRdOptions, autovacuum2) +offsetof(AutoVacOpts2, multixact_freeze_table_age)},
 		{"autovacuum_vacuum_scale_factor", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, autovacuum) +offsetof(AutoVacOpts, vacuum_scale_factor)},
 		{"autovacuum_analyze_scale_factor", RELOPT_TYPE_REAL,
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index d749f70..8ef59e6 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2430,10 +2430,11 @@ typedef struct VacuumStmt
 	int			options;		/* OR of VacuumOption flags */
 	int			freeze_min_age; /* min freeze age, or -1 to use default */
 	int			freeze_table_age;		/* age at which to scan whole table */
-	int			multixact_freeze_min_age; /* min multixact freeze age, or -1 to use default */
-	int			multixact_freeze_table_age; /* multixact age at which to scan whole table */
 	RangeVar   *relation;		/* single table to process, or NULL */
 	List	   *va_cols;		/* list of column names, or NIL for all */
+	/* place these at the end, to avoid ABI break within 9.3 branch */
+	int			multixact_freeze_min_age; /* min multixact freeze age, or -1 to use default */
+	int			multixact_freeze_table_age; /* multixact age at which to scan whole table */
 } VacuumStmt;
 
 /* ----------------------
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 47ae106..53d5690 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -187,7 +187,10 @@ typedef struct RelationData
  * be applied to relations that use this format or a superset for
  * private options data.
  */
- /* autovacuum-related reloptions. */
+ /* autovacuum-related reloptions.
+  *
+  * Split in two to avoid ABI break.
+  */
 typedef struct AutoVacOpts
 {
 	bool		enabled;
@@ -198,19 +201,24 @@ typedef struct AutoVacOpts
 	int			freeze_min_age;
 	int			freeze_max_age;
 	int			freeze_table_age;
-	int			multixact_freeze_min_age;
-	int			multixact_freeze_max_age;
-	int			multixact_freeze_table_age;
 	float8		vacuum_scale_factor;
 	float8		analyze_scale_factor;
 } AutoVacOpts;
 
+typedef struct AutoVacOpts2
+{
+	  int		multixact_freeze_min_age;
+	  int		multixact_freeze_max_age;
+	  int		multixact_freeze_table_age;
+} AutoVacOpts2;
+
 typedef struct StdRdOptions
 {
 	int32		vl_len_;		/* varlena header (do not touch directly!) */
 	int			fillfactor;		/* page fill factor in percent (0..100) */
 	AutoVacOpts autovacuum;		/* autovacuum-related options */
 	bool		security_barrier;		/* for views */
+	AutoVacOpts2 autovacuum2;	/* rest of autovacuum options */
 } StdRdOptions;
 
 #define HEAP_MIN_FILLFACTOR			10