diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c
index d2510ee6480..70278c4f932 100644
--- a/contrib/amcheck/verify_nbtree.c
+++ b/contrib/amcheck/verify_nbtree.c
@@ -691,7 +691,7 @@ bt_check_level_from_leftmost(BtreeCheckState *state, BtreeLevel level)
 		state->target = palloc_btree_page(state, state->targetblock);
 		state->targetlsn = PageGetLSN(state->target);
 
-		opaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+		opaque = BTPageGetOpaque(state->target);
 
 		if (P_IGNORE(opaque))
 		{
@@ -927,7 +927,7 @@ bt_recheck_sibling_links(BtreeCheckState *state,
 		LockBuffer(lbuf, BT_READ);
 		_bt_checkpage(state->rel, lbuf);
 		page = BufferGetPage(lbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		if (P_ISDELETED(opaque))
 		{
 			/*
@@ -951,7 +951,7 @@ bt_recheck_sibling_links(BtreeCheckState *state,
 			LockBuffer(newtargetbuf, BT_READ);
 			_bt_checkpage(state->rel, newtargetbuf);
 			page = BufferGetPage(newtargetbuf);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 			/* btpo_prev_from_target may have changed; update it */
 			btpo_prev_from_target = opaque->btpo_prev;
 		}
@@ -1049,7 +1049,7 @@ bt_target_page_check(BtreeCheckState *state)
 	OffsetNumber max;
 	BTPageOpaque topaque;
 
-	topaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+	topaque = BTPageGetOpaque(state->target);
 	max = PageGetMaxOffsetNumber(state->target);
 
 	elog(DEBUG2, "verifying %u items on %s block %u", max,
@@ -1478,7 +1478,7 @@ bt_target_page_check(BtreeCheckState *state)
 					/* Get fresh copy of target page */
 					state->target = palloc_btree_page(state, state->targetblock);
 					/* Note that we deliberately do not update target LSN */
-					topaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+					topaque = BTPageGetOpaque(state->target);
 
 					/*
 					 * All !readonly checks now performed; just return
@@ -1552,7 +1552,7 @@ bt_right_page_check_scankey(BtreeCheckState *state)
 	OffsetNumber nline;
 
 	/* Determine target's next block number */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+	opaque = BTPageGetOpaque(state->target);
 
 	/* If target is already rightmost, no right sibling; nothing to do here */
 	if (P_RIGHTMOST(opaque))
@@ -1588,7 +1588,7 @@ bt_right_page_check_scankey(BtreeCheckState *state)
 		CHECK_FOR_INTERRUPTS();
 
 		rightpage = palloc_btree_page(state, targetnext);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(rightpage);
+		opaque = BTPageGetOpaque(rightpage);
 
 		if (!P_IGNORE(opaque) || P_RIGHTMOST(opaque))
 			break;
@@ -1893,7 +1893,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 		else
 			page = palloc_btree_page(state, blkno);
 
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		/* The first page we visit at the level should be leftmost */
 		if (first && !BlockNumberIsValid(state->prevrightlink) && !P_LEFTMOST(opaque))
@@ -1971,7 +1971,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 			else
 				pivotkey_offset = target_downlinkoffnum;
 
-			topaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+			topaque = BTPageGetOpaque(state->target);
 
 			if (!offset_is_negative_infinity(topaque, pivotkey_offset))
 			{
@@ -2128,9 +2128,9 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey,
 	 * Check all items, rather than checking just the first and trusting that
 	 * the operator class obeys the transitive law.
 	 */
-	topaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+	topaque = BTPageGetOpaque(state->target);
 	child = palloc_btree_page(state, childblock);
-	copaque = (BTPageOpaque) PageGetSpecialPointer(child);
+	copaque = BTPageGetOpaque(child);
 	maxoffset = PageGetMaxOffsetNumber(child);
 
 	/*
@@ -2235,7 +2235,7 @@ static void
 bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 						  BlockNumber blkno, Page page)
 {
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	ItemId		itemid;
 	IndexTuple	itup;
 	Page		child;
@@ -2319,7 +2319,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 		CHECK_FOR_INTERRUPTS();
 
 		child = palloc_btree_page(state, childblk);
-		copaque = (BTPageOpaque) PageGetSpecialPointer(child);
+		copaque = BTPageGetOpaque(child);
 
 		if (P_ISLEAF(copaque))
 			break;
@@ -2780,7 +2780,7 @@ invariant_l_offset(BtreeCheckState *state, BTScanInsert key,
 		bool		nonpivot;
 
 		ritup = (IndexTuple) PageGetItem(state->target, itemid);
-		topaque = (BTPageOpaque) PageGetSpecialPointer(state->target);
+		topaque = BTPageGetOpaque(state->target);
 		nonpivot = P_ISLEAF(topaque) && upperbound >= P_FIRSTDATAKEY(topaque);
 
 		/* Get number of keys + heap TID for item to the right */
@@ -2895,7 +2895,7 @@ invariant_l_nontarget_offset(BtreeCheckState *state, BTScanInsert key,
 		bool		nonpivot;
 
 		child = (IndexTuple) PageGetItem(nontarget, itemid);
-		copaque = (BTPageOpaque) PageGetSpecialPointer(nontarget);
+		copaque = BTPageGetOpaque(nontarget);
 		nonpivot = P_ISLEAF(copaque) && upperbound >= P_FIRSTDATAKEY(copaque);
 
 		/* Get number of keys + heap TID for child/non-target item */
@@ -2954,7 +2954,7 @@ palloc_btree_page(BtreeCheckState *state, BlockNumber blocknum)
 	memcpy(page, BufferGetPage(buffer), BLCKSZ);
 	UnlockReleaseBuffer(buffer);
 
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	if (P_ISMETA(opaque) && blocknum != BTREE_METAPAGE)
 		ereport(ERROR,
diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 7651c59bbf9..3daa31c84da 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -93,7 +93,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat)
 	Page		page = BufferGetPage(buffer);
 	PageHeader	phdr = (PageHeader) page;
 	OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	int			item_size = 0;
 	int			off;
 
@@ -525,7 +525,7 @@ bt_page_items_internal(PG_FUNCTION_ARGS, enum pageinspect_version ext_version)
 
 		uargs->offset = FirstOffsetNumber;
 
-		opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page);
+		opaque = BTPageGetOpaque(uargs->page);
 
 		if (!P_ISDELETED(opaque))
 			fctx->max_calls = PageGetMaxOffsetNumber(uargs->page);
@@ -622,7 +622,7 @@ bt_page_items_bytea(PG_FUNCTION_ARGS)
 							   (int) MAXALIGN(sizeof(BTPageOpaqueData)),
 							   (int) PageGetSpecialSize(uargs->page))));
 
-		opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page);
+		opaque = BTPageGetOpaque(uargs->page);
 
 		if (P_ISMETA(opaque))
 			ereport(ERROR,
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 6de21d66089..69af7b962ff 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -72,7 +72,7 @@ verify_hash_page(bytea *raw_page, int flags)
 							   (int) MAXALIGN(sizeof(HashPageOpaqueData)),
 							   (int) PageGetSpecialSize(page))));
 
-		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque = HashPageGetOpaque(page);
 		if (pageopaque->hasho_page_id != HASHO_PAGE_ID)
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
@@ -154,7 +154,7 @@ static void
 GetHashPageStatistics(Page page, HashPageStat *stat)
 {
 	OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
-	HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	HashPageOpaque opaque = HashPageGetOpaque(page);
 	int			off;
 
 	stat->dead_items = stat->live_items = 0;
@@ -206,7 +206,7 @@ hash_page_type(PG_FUNCTION_ARGS)
 		type = "unused";
 	else
 	{
-		opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		opaque = HashPageGetOpaque(page);
 
 		/* page type (flags) */
 		pagetype = opaque->hasho_flag & LH_PAGE_TYPE;
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index 6c4b053dd07..e1048e47ff3 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -281,7 +281,7 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo)
 		LockBuffer(buffer, BUFFER_LOCK_SHARE);
 
 		page = BufferGetPage(buffer);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		/*
 		 * Determine page type, and update totals.
@@ -641,7 +641,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 			HashPageOpaque opaque;
 			int			pagetype;
 
-			opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+			opaque = HashPageGetOpaque(page);
 			pagetype = opaque->hasho_flag & LH_PAGE_TYPE;
 
 			if (pagetype == LH_BUCKET_PAGE)
diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c
index c9b8f01f9b4..30945669081 100644
--- a/contrib/pgstattuple/pgstattuple.c
+++ b/contrib/pgstattuple/pgstattuple.c
@@ -415,7 +415,7 @@ pgstat_btree_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno,
 	{
 		BTPageOpaque opaque;
 
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		if (P_IGNORE(opaque))
 		{
 			/* deleted or half-dead page */
@@ -452,7 +452,7 @@ pgstat_hash_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno,
 	{
 		HashPageOpaque opaque;
 
-		opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		opaque = HashPageGetOpaque(page);
 		switch (opaque->hasho_flag & LH_PAGE_TYPE)
 		{
 			case LH_UNUSED_PAGE:
diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c
index a259a301fa8..fd1a7119b6c 100644
--- a/src/backend/access/hash/hash.c
+++ b/src/backend/access/hash/hash.c
@@ -515,7 +515,7 @@ loop_top:
 		_hash_checkpage(rel, buf, LH_BUCKET_PAGE);
 
 		page = BufferGetPage(buf);
-		bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		bucket_opaque = HashPageGetOpaque(page);
 
 		/*
 		 * If the bucket contains tuples that are moved by split, then we need
@@ -717,7 +717,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf,
 		vacuum_delay_point();
 
 		page = BufferGetPage(buf);
-		opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		opaque = HashPageGetOpaque(page);
 
 		/* Scan each tuple in page */
 		maxoffno = PageGetMaxOffsetNumber(page);
@@ -884,7 +884,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf,
 		Page		page;
 
 		page = BufferGetPage(bucket_buf);
-		bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		bucket_opaque = HashPageGetOpaque(page);
 
 		/* No ereport(ERROR) until changes are logged */
 		START_CRIT_SECTION();
diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c
index 55937b9a68e..62dbfc3a5d1 100644
--- a/src/backend/access/hash/hash_xlog.c
+++ b/src/backend/access/hash/hash_xlog.c
@@ -203,7 +203,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record)
 				  true);
 	/* update backlink */
 	ovflpage = BufferGetPage(ovflbuf);
-	ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage);
+	ovflopaque = HashPageGetOpaque(ovflpage);
 	ovflopaque->hasho_prevblkno = leftblk;
 
 	PageSetLSN(ovflpage, lsn);
@@ -215,7 +215,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record)
 		HashPageOpaque leftopaque;
 
 		leftpage = BufferGetPage(leftbuf);
-		leftopaque = (HashPageOpaque) PageGetSpecialPointer(leftpage);
+		leftopaque = HashPageGetOpaque(leftpage);
 		leftopaque->hasho_nextblkno = rightblk;
 
 		PageSetLSN(leftpage, lsn);
@@ -342,7 +342,7 @@ hash_xlog_split_allocate_page(XLogReaderState *record)
 		HashPageOpaque oldopaque;
 
 		oldpage = BufferGetPage(oldbuf);
-		oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage);
+		oldopaque = HashPageGetOpaque(oldpage);
 
 		oldopaque->hasho_flag = xlrec->old_bucket_flag;
 		oldopaque->hasho_prevblkno = xlrec->new_bucket;
@@ -465,7 +465,7 @@ hash_xlog_split_complete(XLogReaderState *record)
 		HashPageOpaque oldopaque;
 
 		oldpage = BufferGetPage(oldbuf);
-		oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage);
+		oldopaque = HashPageGetOpaque(oldpage);
 
 		oldopaque->hasho_flag = xlrec->old_bucket_flag;
 
@@ -488,7 +488,7 @@ hash_xlog_split_complete(XLogReaderState *record)
 		HashPageOpaque nopaque;
 
 		newpage = BufferGetPage(newbuf);
-		nopaque = (HashPageOpaque) PageGetSpecialPointer(newpage);
+		nopaque = HashPageGetOpaque(newpage);
 
 		nopaque->hasho_flag = xlrec->new_bucket_flag;
 
@@ -710,7 +710,7 @@ hash_xlog_squeeze_page(XLogReaderState *record)
 		 */
 		if (xldata->is_prev_bucket_same_wrt)
 		{
-			HashPageOpaque writeopaque = (HashPageOpaque) PageGetSpecialPointer(writepage);
+			HashPageOpaque writeopaque = HashPageGetOpaque(writepage);
 
 			writeopaque->hasho_nextblkno = xldata->nextblkno;
 		}
@@ -729,7 +729,7 @@ hash_xlog_squeeze_page(XLogReaderState *record)
 
 		_hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf));
 
-		ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage);
+		ovflopaque = HashPageGetOpaque(ovflpage);
 
 		ovflopaque->hasho_prevblkno = InvalidBlockNumber;
 		ovflopaque->hasho_nextblkno = InvalidBlockNumber;
@@ -748,7 +748,7 @@ hash_xlog_squeeze_page(XLogReaderState *record)
 		XLogReadBufferForRedo(record, 3, &prevbuf) == BLK_NEEDS_REDO)
 	{
 		Page		prevpage = BufferGetPage(prevbuf);
-		HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage);
+		HashPageOpaque prevopaque = HashPageGetOpaque(prevpage);
 
 		prevopaque->hasho_nextblkno = xldata->nextblkno;
 
@@ -766,7 +766,7 @@ hash_xlog_squeeze_page(XLogReaderState *record)
 		if (XLogReadBufferForRedo(record, 4, &nextbuf) == BLK_NEEDS_REDO)
 		{
 			Page		nextpage = BufferGetPage(nextbuf);
-			HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage);
+			HashPageOpaque nextopaque = HashPageGetOpaque(nextpage);
 
 			nextopaque->hasho_prevblkno = xldata->prevblkno;
 
@@ -903,7 +903,7 @@ hash_xlog_delete(XLogReaderState *record)
 		{
 			HashPageOpaque pageopaque;
 
-			pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+			pageopaque = HashPageGetOpaque(page);
 			pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
 		}
 
@@ -933,7 +933,7 @@ hash_xlog_split_cleanup(XLogReaderState *record)
 
 		page = (Page) BufferGetPage(buffer);
 
-		bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		bucket_opaque = HashPageGetOpaque(page);
 		bucket_opaque->hasho_flag &= ~LH_BUCKET_NEEDS_SPLIT_CLEANUP;
 		PageSetLSN(page, lsn);
 		MarkBufferDirty(buffer);
@@ -1024,7 +1024,7 @@ hash_xlog_vacuum_one_page(XLogReaderState *record)
 		 * Mark the page as not containing any LP_DEAD items. See comments in
 		 * _hash_vacuum_one_page() for details.
 		 */
-		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque = HashPageGetOpaque(page);
 		pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
 
 		PageSetLSN(page, lsn);
@@ -1116,7 +1116,7 @@ hash_mask(char *pagedata, BlockNumber blkno)
 	mask_page_hint_bits(page);
 	mask_unused_space(page);
 
-	opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	opaque = HashPageGetOpaque(page);
 
 	pagetype = opaque->hasho_flag & LH_PAGE_TYPE;
 	if (pagetype == LH_UNUSED_PAGE)
diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c
index faf609c1574..4f2fecb908e 100644
--- a/src/backend/access/hash/hashinsert.c
+++ b/src/backend/access/hash/hashinsert.c
@@ -95,7 +95,7 @@ restart_insert:
 	bucket_buf = buf;
 
 	page = BufferGetPage(buf);
-	pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	pageopaque = HashPageGetOpaque(page);
 	bucket = pageopaque->hasho_bucket;
 
 	/*
@@ -183,7 +183,7 @@ restart_insert:
 			/* should fit now, given test above */
 			Assert(PageGetFreeSpace(page) >= itemsz);
 		}
-		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque = HashPageGetOpaque(page);
 		Assert((pageopaque->hasho_flag & LH_PAGE_TYPE) == LH_OVERFLOW_PAGE);
 		Assert(pageopaque->hasho_bucket == bucket);
 	}
@@ -384,7 +384,7 @@ _hash_vacuum_one_page(Relation rel, Relation hrel, Buffer metabuf, Buffer buf)
 		 * check it. Remember that LH_PAGE_HAS_DEAD_TUPLES is only a hint
 		 * anyway.
 		 */
-		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque = HashPageGetOpaque(page);
 		pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
 
 		metap = HashPageGetMeta(BufferGetPage(metabuf));
diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c
index 48368751963..e34cfc302d3 100644
--- a/src/backend/access/hash/hashovfl.c
+++ b/src/backend/access/hash/hashovfl.c
@@ -159,7 +159,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin)
 		BlockNumber nextblkno;
 
 		page = BufferGetPage(buf);
-		pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		pageopaque = HashPageGetOpaque(page);
 		nextblkno = pageopaque->hasho_nextblkno;
 
 		if (!BlockNumberIsValid(nextblkno))
@@ -364,7 +364,7 @@ found:
 
 	/* initialize new overflow page */
 	ovflpage = BufferGetPage(ovflbuf);
-	ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage);
+	ovflopaque = HashPageGetOpaque(ovflpage);
 	ovflopaque->hasho_prevblkno = BufferGetBlockNumber(buf);
 	ovflopaque->hasho_nextblkno = InvalidBlockNumber;
 	ovflopaque->hasho_bucket = pageopaque->hasho_bucket;
@@ -516,7 +516,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf,
 	_hash_checkpage(rel, ovflbuf, LH_OVERFLOW_PAGE);
 	ovflblkno = BufferGetBlockNumber(ovflbuf);
 	ovflpage = BufferGetPage(ovflbuf);
-	ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage);
+	ovflopaque = HashPageGetOpaque(ovflpage);
 	nextblkno = ovflopaque->hasho_nextblkno;
 	prevblkno = ovflopaque->hasho_prevblkno;
 	writeblkno = BufferGetBlockNumber(wbuf);
@@ -600,7 +600,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf,
 	 */
 	_hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf));
 
-	ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage);
+	ovflopaque = HashPageGetOpaque(ovflpage);
 
 	ovflopaque->hasho_prevblkno = InvalidBlockNumber;
 	ovflopaque->hasho_nextblkno = InvalidBlockNumber;
@@ -613,7 +613,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf,
 	if (BufferIsValid(prevbuf))
 	{
 		Page		prevpage = BufferGetPage(prevbuf);
-		HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage);
+		HashPageOpaque prevopaque = HashPageGetOpaque(prevpage);
 
 		Assert(prevopaque->hasho_bucket == bucket);
 		prevopaque->hasho_nextblkno = nextblkno;
@@ -622,7 +622,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf,
 	if (BufferIsValid(nextbuf))
 	{
 		Page		nextpage = BufferGetPage(nextbuf);
-		HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage);
+		HashPageOpaque nextopaque = HashPageGetOpaque(nextpage);
 
 		Assert(nextopaque->hasho_bucket == bucket);
 		nextopaque->hasho_prevblkno = prevblkno;
@@ -751,7 +751,7 @@ _hash_initbitmapbuffer(Buffer buf, uint16 bmsize, bool initpage)
 		_hash_pageinit(pg, BufferGetPageSize(buf));
 
 	/* initialize the page's special space */
-	op = (HashPageOpaque) PageGetSpecialPointer(pg);
+	op = HashPageGetOpaque(pg);
 	op->hasho_prevblkno = InvalidBlockNumber;
 	op->hasho_nextblkno = InvalidBlockNumber;
 	op->hasho_bucket = InvalidBucket;
@@ -824,7 +824,7 @@ _hash_squeezebucket(Relation rel,
 	wblkno = bucket_blkno;
 	wbuf = bucket_buf;
 	wpage = BufferGetPage(wbuf);
-	wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage);
+	wopaque = HashPageGetOpaque(wpage);
 
 	/*
 	 * if there aren't any overflow pages, there's nothing to squeeze. caller
@@ -855,7 +855,7 @@ _hash_squeezebucket(Relation rel,
 										  LH_OVERFLOW_PAGE,
 										  bstrategy);
 		rpage = BufferGetPage(rbuf);
-		ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage);
+		ropaque = HashPageGetOpaque(rpage);
 		Assert(ropaque->hasho_bucket == bucket);
 	} while (BlockNumberIsValid(ropaque->hasho_nextblkno));
 
@@ -1005,7 +1005,7 @@ readpage:
 
 				wbuf = next_wbuf;
 				wpage = BufferGetPage(wbuf);
-				wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage);
+				wopaque = HashPageGetOpaque(wpage);
 				Assert(wopaque->hasho_bucket == bucket);
 				retain_pin = false;
 
@@ -1076,7 +1076,7 @@ readpage:
 										  LH_OVERFLOW_PAGE,
 										  bstrategy);
 		rpage = BufferGetPage(rbuf);
-		ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage);
+		ropaque = HashPageGetOpaque(rpage);
 		Assert(ropaque->hasho_bucket == bucket);
 	}
 
diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index 28c5297a1dc..39206d19429 100644
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -166,7 +166,7 @@ _hash_initbuf(Buffer buf, uint32 max_bucket, uint32 num_bucket, uint32 flag,
 	if (initpage)
 		_hash_pageinit(page, BufferGetPageSize(buf));
 
-	pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	pageopaque = HashPageGetOpaque(page);
 
 	/*
 	 * Set hasho_prevblkno with current hashm_maxbucket. This value will be
@@ -529,7 +529,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid,
 	if (initpage)
 		_hash_pageinit(page, BufferGetPageSize(buf));
 
-	pageopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	pageopaque = HashPageGetOpaque(page);
 	pageopaque->hasho_prevblkno = InvalidBlockNumber;
 	pageopaque->hasho_nextblkno = InvalidBlockNumber;
 	pageopaque->hasho_bucket = InvalidBucket;
@@ -693,7 +693,7 @@ restart_expand:
 		goto fail;
 
 	opage = BufferGetPage(buf_oblkno);
-	oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
+	oopaque = HashPageGetOpaque(opage);
 
 	/*
 	 * We want to finish the split from a bucket as there is no apparent
@@ -864,7 +864,7 @@ restart_expand:
 	lowmask = metap->hashm_lowmask;
 
 	opage = BufferGetPage(buf_oblkno);
-	oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
+	oopaque = HashPageGetOpaque(opage);
 
 	/*
 	 * Mark the old bucket to indicate that split is in progress.  (At
@@ -883,7 +883,7 @@ restart_expand:
 	 * initialize the new bucket's primary page and mark it to indicate that
 	 * split is in progress.
 	 */
-	nopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+	nopaque = HashPageGetOpaque(npage);
 	nopaque->hasho_prevblkno = maxbucket;
 	nopaque->hasho_nextblkno = InvalidBlockNumber;
 	nopaque->hasho_bucket = new_bucket;
@@ -1010,7 +1010,7 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
 	 */
 	_hash_pageinit(page, BLCKSZ);
 
-	ovflopaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	ovflopaque = HashPageGetOpaque(page);
 
 	ovflopaque->hasho_prevblkno = InvalidBlockNumber;
 	ovflopaque->hasho_nextblkno = InvalidBlockNumber;
@@ -1091,11 +1091,11 @@ _hash_splitbucket(Relation rel,
 
 	bucket_obuf = obuf;
 	opage = BufferGetPage(obuf);
-	oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
+	oopaque = HashPageGetOpaque(opage);
 
 	bucket_nbuf = nbuf;
 	npage = BufferGetPage(nbuf);
-	nopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+	nopaque = HashPageGetOpaque(npage);
 
 	/* Copy the predicate locks from old bucket to new bucket. */
 	PredicateLockPageSplit(rel,
@@ -1198,7 +1198,7 @@ _hash_splitbucket(Relation rel,
 					/* chain to a new overflow page */
 					nbuf = _hash_addovflpage(rel, metabuf, nbuf, (nbuf == bucket_nbuf));
 					npage = BufferGetPage(nbuf);
-					nopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+					nopaque = HashPageGetOpaque(npage);
 				}
 
 				itups[nitups++] = new_itup;
@@ -1251,7 +1251,7 @@ _hash_splitbucket(Relation rel,
 		/* Else, advance to next old page */
 		obuf = _hash_getbuf(rel, oblkno, HASH_READ, LH_OVERFLOW_PAGE);
 		opage = BufferGetPage(obuf);
-		oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
+		oopaque = HashPageGetOpaque(opage);
 	}
 
 	/*
@@ -1264,11 +1264,11 @@ _hash_splitbucket(Relation rel,
 	 */
 	LockBuffer(bucket_obuf, BUFFER_LOCK_EXCLUSIVE);
 	opage = BufferGetPage(bucket_obuf);
-	oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
+	oopaque = HashPageGetOpaque(opage);
 
 	LockBuffer(bucket_nbuf, BUFFER_LOCK_EXCLUSIVE);
 	npage = BufferGetPage(bucket_nbuf);
-	nopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+	nopaque = HashPageGetOpaque(npage);
 
 	START_CRIT_SECTION();
 
@@ -1392,7 +1392,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket,
 			bucket_nbuf = nbuf;
 
 		npage = BufferGetPage(nbuf);
-		npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+		npageopaque = HashPageGetOpaque(npage);
 
 		/* Scan each tuple in new page */
 		nmaxoffnum = PageGetMaxOffsetNumber(npage);
@@ -1446,7 +1446,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket,
 	}
 
 	npage = BufferGetPage(bucket_nbuf);
-	npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
+	npageopaque = HashPageGetOpaque(npage);
 	nbucket = npageopaque->hasho_bucket;
 
 	_hash_splitbucket(rel, metabuf, obucket,
@@ -1587,7 +1587,7 @@ _hash_getbucketbuf_from_hashkey(Relation rel, uint32 hashkey, int access,
 		/* Fetch the primary bucket page for the bucket */
 		buf = _hash_getbuf(rel, blkno, access, LH_BUCKET_PAGE);
 		page = BufferGetPage(buf);
-		opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		opaque = HashPageGetOpaque(page);
 		Assert(opaque->hasho_bucket == bucket);
 		Assert(opaque->hasho_prevblkno != InvalidBlockNumber);
 
diff --git a/src/backend/access/hash/hashsearch.c b/src/backend/access/hash/hashsearch.c
index 7ca542a3fba..524af27409d 100644
--- a/src/backend/access/hash/hashsearch.c
+++ b/src/backend/access/hash/hashsearch.c
@@ -187,7 +187,7 @@ _hash_readnext(IndexScanDesc scan,
 	{
 		*pagep = BufferGetPage(*bufp);
 		TestForOldSnapshot(scan->xs_snapshot, rel, *pagep);
-		*opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep);
+		*opaquep = HashPageGetOpaque(*pagep);
 	}
 }
 
@@ -233,7 +233,7 @@ _hash_readprev(IndexScanDesc scan,
 							 LH_BUCKET_PAGE | LH_OVERFLOW_PAGE);
 		*pagep = BufferGetPage(*bufp);
 		TestForOldSnapshot(scan->xs_snapshot, rel, *pagep);
-		*opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep);
+		*opaquep = HashPageGetOpaque(*pagep);
 
 		/*
 		 * We always maintain the pin on bucket page for whole scan operation,
@@ -258,7 +258,7 @@ _hash_readprev(IndexScanDesc scan,
 
 		LockBuffer(*bufp, BUFFER_LOCK_SHARE);
 		*pagep = BufferGetPage(*bufp);
-		*opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep);
+		*opaquep = HashPageGetOpaque(*pagep);
 
 		/* move to the end of bucket chain */
 		while (BlockNumberIsValid((*opaquep)->hasho_nextblkno))
@@ -352,7 +352,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
 	PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot);
 	page = BufferGetPage(buf);
 	TestForOldSnapshot(scan->xs_snapshot, rel, page);
-	opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	opaque = HashPageGetOpaque(page);
 	bucket = opaque->hasho_bucket;
 
 	so->hashso_bucket_buf = buf;
@@ -398,7 +398,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
 
 		LockBuffer(buf, BUFFER_LOCK_SHARE);
 		page = BufferGetPage(buf);
-		opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		opaque = HashPageGetOpaque(page);
 		Assert(opaque->hasho_bucket == bucket);
 
 		if (H_BUCKET_BEING_POPULATED(opaque))
@@ -463,7 +463,7 @@ _hash_readpage(IndexScanDesc scan, Buffer *bufP, ScanDirection dir)
 	Assert(BufferIsValid(buf));
 	_hash_checkpage(rel, buf, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE);
 	page = BufferGetPage(buf);
-	opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	opaque = HashPageGetOpaque(page);
 
 	so->currPos.buf = buf;
 	so->currPos.currPage = BufferGetBlockNumber(buf);
diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c
index edb6fa968fc..fe37bc47cbb 100644
--- a/src/backend/access/hash/hashutil.c
+++ b/src/backend/access/hash/hashutil.c
@@ -239,7 +239,7 @@ _hash_checkpage(Relation rel, Buffer buf, int flags)
 
 	if (flags)
 	{
-		HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+		HashPageOpaque opaque = HashPageGetOpaque(page);
 
 		if ((opaque->hasho_flag & flags) == 0)
 			ereport(ERROR,
@@ -574,7 +574,7 @@ _hash_kill_items(IndexScanDesc scan)
 		buf = _hash_getbuf(rel, blkno, HASH_READ, LH_OVERFLOW_PAGE);
 
 	page = BufferGetPage(buf);
-	opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+	opaque = HashPageGetOpaque(page);
 	maxoff = PageGetMaxOffsetNumber(page);
 
 	for (i = 0; i < numKilled; i++)
diff --git a/src/backend/access/nbtree/nbtdedup.c b/src/backend/access/nbtree/nbtdedup.c
index 4c48554aec3..3e11805293a 100644
--- a/src/backend/access/nbtree/nbtdedup.c
+++ b/src/backend/access/nbtree/nbtdedup.c
@@ -62,7 +62,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem,
 				minoff,
 				maxoff;
 	Page		page = BufferGetPage(buf);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	Page		newpage;
 	BTDedupState state;
 	Size		pagesaving = 0;
@@ -231,7 +231,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem,
 	 */
 	if (P_HAS_GARBAGE(opaque))
 	{
-		BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage);
+		BTPageOpaque nopaque = BTPageGetOpaque(newpage);
 
 		nopaque->btpo_flags &= ~BTP_HAS_GARBAGE;
 	}
@@ -310,7 +310,7 @@ _bt_bottomupdel_pass(Relation rel, Buffer buf, Relation heapRel,
 				minoff,
 				maxoff;
 	Page		page = BufferGetPage(buf);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	BTDedupState state;
 	TM_IndexDeleteOp delstate;
 	bool		neverdedup;
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 68628ec000d..f6f4af8bfe3 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -329,7 +329,7 @@ _bt_search_insert(Relation rel, BTInsertState insertstate)
 
 			_bt_checkpage(rel, insertstate->buf);
 			page = BufferGetPage(insertstate->buf);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 
 			/*
 			 * Check if the page is still the rightmost leaf page and has
@@ -428,7 +428,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel,
 	InitDirtySnapshot(SnapshotDirty);
 
 	page = BufferGetPage(insertstate->buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	maxoff = PageGetMaxOffsetNumber(page);
 
 	/*
@@ -733,7 +733,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel,
 
 				nbuf = _bt_relandgetbuf(rel, nbuf, nblkno, BT_READ);
 				page = BufferGetPage(nbuf);
-				opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+				opaque = BTPageGetOpaque(page);
 				if (!P_IGNORE(opaque))
 					break;
 				if (P_RIGHTMOST(opaque))
@@ -822,7 +822,7 @@ _bt_findinsertloc(Relation rel,
 	BTPageOpaque opaque;
 	OffsetNumber newitemoff;
 
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/* Check 1/3 of a page restriction */
 	if (unlikely(insertstate->itemsz > BTMaxItemSize(page)))
@@ -888,7 +888,7 @@ _bt_findinsertloc(Relation rel,
 				_bt_stepright(rel, insertstate, stack);
 				/* Update local state after stepping right */
 				page = BufferGetPage(insertstate->buf);
-				opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+				opaque = BTPageGetOpaque(page);
 				/* Assume duplicates (if checkingunique) */
 				uniquedup = true;
 			}
@@ -972,7 +972,7 @@ _bt_findinsertloc(Relation rel,
 			_bt_stepright(rel, insertstate, stack);
 			/* Update local state after stepping right */
 			page = BufferGetPage(insertstate->buf);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 		}
 	}
 
@@ -1030,7 +1030,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack)
 	BlockNumber rblkno;
 
 	page = BufferGetPage(insertstate->buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	rbuf = InvalidBuffer;
 	rblkno = opaque->btpo_next;
@@ -1038,7 +1038,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack)
 	{
 		rbuf = _bt_relandgetbuf(rel, rbuf, rblkno, BT_WRITE);
 		page = BufferGetPage(rbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		/*
 		 * If this page was incompletely split, finish the split now.  We do
@@ -1120,7 +1120,7 @@ _bt_insertonpg(Relation rel,
 	IndexTuple	nposting = NULL;
 
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	isleaf = P_ISLEAF(opaque);
 	isroot = P_ISROOT(opaque);
 	isrightmost = P_RIGHTMOST(opaque);
@@ -1296,7 +1296,7 @@ _bt_insertonpg(Relation rel,
 		if (!isleaf)
 		{
 			Page		cpage = BufferGetPage(cbuf);
-			BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage);
+			BTPageOpaque cpageop = BTPageGetOpaque(cpage);
 
 			Assert(P_INCOMPLETE_SPLIT(cpageop));
 			cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT;
@@ -1504,7 +1504,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	 * only workspace.
 	 */
 	origpage = BufferGetPage(buf);
-	oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage);
+	oopaque = BTPageGetOpaque(origpage);
 	isleaf = P_ISLEAF(oopaque);
 	isrightmost = P_RIGHTMOST(oopaque);
 	maxoff = PageGetMaxOffsetNumber(origpage);
@@ -1540,7 +1540,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	/* Allocate temp buffer for leftpage */
 	leftpage = PageGetTempPage(origpage);
 	_bt_pageinit(leftpage, BufferGetPageSize(buf));
-	lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage);
+	lopaque = BTPageGetOpaque(leftpage);
 
 	/*
 	 * leftpage won't be the root when we're done.  Also, clear the SPLIT_END
@@ -1716,7 +1716,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	rightpage = BufferGetPage(rbuf);
 	rightpagenumber = BufferGetBlockNumber(rbuf);
 	/* rightpage was initialized by _bt_getbuf */
-	ropaque = (BTPageOpaque) PageGetSpecialPointer(rightpage);
+	ropaque = BTPageGetOpaque(rightpage);
 
 	/*
 	 * Finish off remaining leftpage special area fields.  They cannot be set
@@ -1887,7 +1887,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	{
 		sbuf = _bt_getbuf(rel, oopaque->btpo_next, BT_WRITE);
 		spage = BufferGetPage(sbuf);
-		sopaque = (BTPageOpaque) PageGetSpecialPointer(spage);
+		sopaque = BTPageGetOpaque(spage);
 		if (sopaque->btpo_prev != origpagenumber)
 		{
 			memset(rightpage, 0, BufferGetPageSize(rbuf));
@@ -1952,7 +1952,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	if (!isleaf)
 	{
 		Page		cpage = BufferGetPage(cbuf);
-		BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage);
+		BTPageOpaque cpageop = BTPageGetOpaque(cpage);
 
 		cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT;
 		MarkBufferDirty(cbuf);
@@ -2139,7 +2139,7 @@ _bt_insert_parent(Relation rel,
 			BTPageOpaque opaque;
 
 			elog(DEBUG2, "concurrent ROOT page split");
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 
 			/*
 			 * We should never reach here when a leaf page split takes place
@@ -2230,7 +2230,7 @@ void
 _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack)
 {
 	Page		lpage = BufferGetPage(lbuf);
-	BTPageOpaque lpageop = (BTPageOpaque) PageGetSpecialPointer(lpage);
+	BTPageOpaque lpageop = BTPageGetOpaque(lpage);
 	Buffer		rbuf;
 	Page		rpage;
 	BTPageOpaque rpageop;
@@ -2242,7 +2242,7 @@ _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack)
 	/* Lock right sibling, the one missing the downlink */
 	rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE);
 	rpage = BufferGetPage(rbuf);
-	rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage);
+	rpageop = BTPageGetOpaque(rpage);
 
 	/* Could this be a root split? */
 	if (!stack)
@@ -2320,7 +2320,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, BlockNumber child)
 
 		buf = _bt_getbuf(rel, blkno, BT_WRITE);
 		page = BufferGetPage(buf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		if (P_INCOMPLETE_SPLIT(opaque))
 		{
@@ -2451,7 +2451,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
 	lbkno = BufferGetBlockNumber(lbuf);
 	rbkno = BufferGetBlockNumber(rbuf);
 	lpage = BufferGetPage(lbuf);
-	lopaque = (BTPageOpaque) PageGetSpecialPointer(lpage);
+	lopaque = BTPageGetOpaque(lpage);
 
 	/* get a new root page */
 	rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE);
@@ -2492,11 +2492,11 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
 		_bt_upgrademetapage(metapg);
 
 	/* set btree special data */
-	rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
+	rootopaque = BTPageGetOpaque(rootpage);
 	rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE;
 	rootopaque->btpo_flags = BTP_ROOT;
 	rootopaque->btpo_level =
-		((BTPageOpaque) PageGetSpecialPointer(lpage))->btpo_level + 1;
+		(BTPageGetOpaque(lpage))->btpo_level + 1;
 	rootopaque->btpo_cycleid = 0;
 
 	/* update metapage data */
@@ -2680,7 +2680,7 @@ _bt_delete_or_dedup_one_page(Relation rel, Relation heapRel,
 	Buffer		buffer = insertstate->buf;
 	BTScanInsert itup_key = insertstate->itup_key;
 	Page		page = BufferGetPage(buffer);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 
 	Assert(P_ISLEAF(opaque));
 	Assert(simpleonly || itup_key->heapkeyspace);
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index 6b5f01e1d07..20adb602a4d 100644
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -85,7 +85,7 @@ _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level,
 	metad->btm_last_cleanup_num_heap_tuples = -1.0;
 	metad->btm_allequalimage = allequalimage;
 
-	metaopaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	metaopaque = BTPageGetOpaque(page);
 	metaopaque->btpo_flags = BTP_META;
 
 	/*
@@ -112,7 +112,7 @@ _bt_upgrademetapage(Page page)
 	BTPageOpaque metaopaque PG_USED_FOR_ASSERTS_ONLY;
 
 	metad = BTPageGetMeta(page);
-	metaopaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	metaopaque = BTPageGetOpaque(page);
 
 	/* It must be really a meta page of upgradable version */
 	Assert(metaopaque->btpo_flags & BTP_META);
@@ -148,7 +148,7 @@ _bt_getmeta(Relation rel, Buffer metabuf)
 	BTMetaPageData *metad;
 
 	metapg = BufferGetPage(metabuf);
-	metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg);
+	metaopaque = BTPageGetOpaque(metapg);
 	metad = BTPageGetMeta(metapg);
 
 	/* sanity-check the metapage */
@@ -372,7 +372,7 @@ _bt_getroot(Relation rel, int access)
 
 		rootbuf = _bt_getbuf(rel, rootblkno, BT_READ);
 		rootpage = BufferGetPage(rootbuf);
-		rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
+		rootopaque = BTPageGetOpaque(rootpage);
 
 		/*
 		 * Since the cache might be stale, we check the page more carefully
@@ -440,7 +440,7 @@ _bt_getroot(Relation rel, int access)
 		rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE);
 		rootblkno = BufferGetBlockNumber(rootbuf);
 		rootpage = BufferGetPage(rootbuf);
-		rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
+		rootopaque = BTPageGetOpaque(rootpage);
 		rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE;
 		rootopaque->btpo_flags = (BTP_LEAF | BTP_ROOT);
 		rootopaque->btpo_level = 0;
@@ -534,7 +534,7 @@ _bt_getroot(Relation rel, int access)
 		{
 			rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ);
 			rootpage = BufferGetPage(rootbuf);
-			rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
+			rootopaque = BTPageGetOpaque(rootpage);
 
 			if (!P_IGNORE(rootopaque))
 				break;
@@ -598,7 +598,7 @@ _bt_gettrueroot(Relation rel)
 
 	metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_READ);
 	metapg = BufferGetPage(metabuf);
-	metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg);
+	metaopaque = BTPageGetOpaque(metapg);
 	metad = BTPageGetMeta(metapg);
 
 	if (!P_ISMETA(metaopaque) ||
@@ -637,7 +637,7 @@ _bt_gettrueroot(Relation rel)
 	{
 		rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ);
 		rootpage = BufferGetPage(rootbuf);
-		rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage);
+		rootopaque = BTPageGetOpaque(rootpage);
 
 		if (!P_IGNORE(rootopaque))
 			break;
@@ -1220,7 +1220,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf,
 	 * We can clear the vacuum cycle ID since this page has certainly been
 	 * processed by the current vacuum scan.
 	 */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	opaque->btpo_cycleid = 0;
 
 	/*
@@ -1338,7 +1338,7 @@ _bt_delitems_delete(Relation rel, Buffer buf, TransactionId latestRemovedXid,
 	 * Unlike _bt_delitems_vacuum, we *must not* clear the vacuum cycle ID at
 	 * this point.  The VACUUM command alone controls vacuum cycle IDs.
 	 */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/*
 	 * Clear the BTP_HAS_GARBAGE page flag.
@@ -1718,7 +1718,7 @@ _bt_leftsib_splitflag(Relation rel, BlockNumber leftsib, BlockNumber target)
 
 	buf = _bt_getbuf(rel, leftsib, BT_READ);
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/*
 	 * If the left sibling was concurrently split, so that its next-pointer
@@ -1773,7 +1773,7 @@ _bt_rightsib_halfdeadflag(Relation rel, BlockNumber leafrightsib)
 
 	buf = _bt_getbuf(rel, leafrightsib, BT_READ);
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque));
 	result = P_ISHALFDEAD(opaque);
@@ -1842,7 +1842,7 @@ _bt_pagedel(Relation rel, Buffer leafbuf, BTVacState *vstate)
 	for (;;)
 	{
 		page = BufferGetPage(leafbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		/*
 		 * Internal pages are never deleted directly, only as part of deleting
@@ -2099,7 +2099,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	IndexTupleData trunctuple;
 
 	page = BufferGetPage(leafbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	Assert(!P_RIGHTMOST(opaque) && !P_ISROOT(opaque) &&
 		   P_ISLEAF(opaque) && !P_IGNORE(opaque) &&
@@ -2154,7 +2154,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	 * before entering the critical section --- otherwise it'd be a PANIC.
 	 */
 	page = BufferGetPage(subtreeparent);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 #ifdef USE_ASSERT_CHECKING
 
@@ -2201,7 +2201,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	 * nbtree/README.
 	 */
 	page = BufferGetPage(subtreeparent);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	itemid = PageGetItemId(page, poffset);
 	itup = (IndexTuple) PageGetItem(page, itemid);
@@ -2216,7 +2216,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	 * is set to InvalidBlockNumber.
 	 */
 	page = BufferGetPage(leafbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	opaque->btpo_flags |= BTP_HALF_DEAD;
 
 	Assert(PageGetMaxOffsetNumber(page) == P_HIKEY);
@@ -2253,7 +2253,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 		XLogRegisterBuffer(1, subtreeparent, REGBUF_STANDARD);
 
 		page = BufferGetPage(leafbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		xlrec.leftblk = opaque->btpo_prev;
 		xlrec.rightblk = opaque->btpo_next;
 
@@ -2325,7 +2325,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	BlockNumber leaftopparent;
 
 	page = BufferGetPage(leafbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque) && P_ISHALFDEAD(opaque));
 
@@ -2364,7 +2364,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 		/* Fetch the block number of the target's left sibling */
 		buf = _bt_getbuf(rel, target, BT_READ);
 		page = BufferGetPage(buf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		leftsib = opaque->btpo_prev;
 		targetlevel = opaque->btpo_level;
 		Assert(targetlevel > 0);
@@ -2391,7 +2391,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	{
 		lbuf = _bt_getbuf(rel, leftsib, BT_WRITE);
 		page = BufferGetPage(lbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		while (P_ISDELETED(opaque) || opaque->btpo_next != target)
 		{
 			bool		leftsibvalid = true;
@@ -2441,7 +2441,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 			/* step right one page */
 			lbuf = _bt_getbuf(rel, leftsib, BT_WRITE);
 			page = BufferGetPage(lbuf);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 		}
 	}
 	else
@@ -2450,7 +2450,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	/* Next write-lock the target page itself */
 	_bt_lockbuf(rel, buf, BT_WRITE);
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/*
 	 * Check page is still empty etc, else abandon deletion.  This is just for
@@ -2505,7 +2505,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	rightsib = opaque->btpo_next;
 	rbuf = _bt_getbuf(rel, rightsib, BT_WRITE);
 	page = BufferGetPage(rbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	if (opaque->btpo_prev != target)
 		ereport(ERROR,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
@@ -2528,7 +2528,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	if (leftsib == P_NONE && rightsib_is_rightmost)
 	{
 		page = BufferGetPage(rbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		if (P_RIGHTMOST(opaque))
 		{
 			/* rightsib will be the only one left on the level */
@@ -2565,12 +2565,12 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	if (BufferIsValid(lbuf))
 	{
 		page = BufferGetPage(lbuf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		Assert(opaque->btpo_next == target);
 		opaque->btpo_next = rightsib;
 	}
 	page = BufferGetPage(rbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	Assert(opaque->btpo_prev == target);
 	opaque->btpo_prev = leftsib;
 
@@ -2599,7 +2599,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno,
 	 * of that scan.
 	 */
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	Assert(P_ISHALFDEAD(opaque) || !P_ISLEAF(opaque));
 
 	/*
@@ -2814,7 +2814,7 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack,
 	parentoffset = stack->bts_offset;
 
 	page = BufferGetPage(pbuf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	maxoff = PageGetMaxOffsetNumber(page);
 	leftsibparent = opaque->btpo_prev;
 
diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
index dacf3f7a587..06131f23d4b 100644
--- a/src/backend/access/nbtree/nbtree.c
+++ b/src/backend/access/nbtree/nbtree.c
@@ -1070,7 +1070,7 @@ backtrack:
 	if (!PageIsNew(page))
 	{
 		_bt_checkpage(rel, buf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 	}
 
 	Assert(blkno <= scanblkno);
diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c
index 9d82d4904d8..c74543bfde2 100644
--- a/src/backend/access/nbtree/nbtsearch.c
+++ b/src/backend/access/nbtree/nbtsearch.c
@@ -134,7 +134,7 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access,
 
 		/* if this is a leaf page, we're done */
 		page = BufferGetPage(*bufP);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		if (P_ISLEAF(opaque))
 			break;
 
@@ -268,7 +268,7 @@ _bt_moveright(Relation rel,
 	{
 		page = BufferGetPage(buf);
 		TestForOldSnapshot(snapshot, rel, page);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		if (P_RIGHTMOST(opaque))
 			break;
@@ -347,7 +347,7 @@ _bt_binsrch(Relation rel,
 				cmpval;
 
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/* Requesting nextkey semantics while using scantid seems nonsensical */
 	Assert(!key->nextkey || key->scantid == NULL);
@@ -451,7 +451,7 @@ _bt_binsrch_insert(Relation rel, BTInsertState insertstate)
 				cmpval;
 
 	page = BufferGetPage(insertstate->buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	Assert(P_ISLEAF(opaque));
 	Assert(!key->nextkey);
@@ -659,7 +659,7 @@ _bt_compare(Relation rel,
 			OffsetNumber offnum)
 {
 	TupleDesc	itupdesc = RelationGetDescr(rel);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	IndexTuple	itup;
 	ItemPointer heapTid;
 	ScanKey		scankey;
@@ -1536,7 +1536,7 @@ _bt_readpage(IndexScanDesc scan, ScanDirection dir, OffsetNumber offnum)
 	Assert(BufferIsValid(so->currPos.buf));
 
 	page = BufferGetPage(so->currPos.buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	/* allow next page be processed by parallel worker */
 	if (scan->parallel_scan)
@@ -2007,7 +2007,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir)
 			so->currPos.buf = _bt_getbuf(rel, blkno, BT_READ);
 			page = BufferGetPage(so->currPos.buf);
 			TestForOldSnapshot(scan->xs_snapshot, rel, page);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 			/* check for deleted page */
 			if (!P_IGNORE(opaque))
 			{
@@ -2110,7 +2110,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir)
 			 */
 			page = BufferGetPage(so->currPos.buf);
 			TestForOldSnapshot(scan->xs_snapshot, rel, page);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 			if (!P_IGNORE(opaque))
 			{
 				PredicateLockPage(rel, BufferGetBlockNumber(so->currPos.buf), scan->xs_snapshot);
@@ -2191,7 +2191,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot)
 	BTPageOpaque opaque;
 
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	for (;;)
 	{
@@ -2216,7 +2216,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot)
 		buf = _bt_getbuf(rel, blkno, BT_READ);
 		page = BufferGetPage(buf);
 		TestForOldSnapshot(snapshot, rel, page);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 
 		/*
 		 * If this isn't the page we want, walk right till we find what we
@@ -2243,14 +2243,14 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot)
 			buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ);
 			page = BufferGetPage(buf);
 			TestForOldSnapshot(snapshot, rel, page);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 		}
 
 		/* Return to the original page to see what's up */
 		buf = _bt_relandgetbuf(rel, buf, obknum, BT_READ);
 		page = BufferGetPage(buf);
 		TestForOldSnapshot(snapshot, rel, page);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		if (P_ISDELETED(opaque))
 		{
 			/*
@@ -2268,7 +2268,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot)
 				buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ);
 				page = BufferGetPage(buf);
 				TestForOldSnapshot(snapshot, rel, page);
-				opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+				opaque = BTPageGetOpaque(page);
 				if (!P_ISDELETED(opaque))
 					break;
 			}
@@ -2329,7 +2329,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost,
 
 	page = BufferGetPage(buf);
 	TestForOldSnapshot(snapshot, rel, page);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 
 	for (;;)
 	{
@@ -2349,7 +2349,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost,
 			buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ);
 			page = BufferGetPage(buf);
 			TestForOldSnapshot(snapshot, rel, page);
-			opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+			opaque = BTPageGetOpaque(page);
 		}
 
 		/* Done? */
@@ -2372,7 +2372,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost,
 
 		buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ);
 		page = BufferGetPage(buf);
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 	}
 
 	return buf;
@@ -2418,7 +2418,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir)
 
 	PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot);
 	page = BufferGetPage(buf);
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	Assert(P_ISLEAF(opaque));
 
 	if (ScanDirectionIsForward(dir))
diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c
index 8a19de2f66c..c074513efa1 100644
--- a/src/backend/access/nbtree/nbtsort.c
+++ b/src/backend/access/nbtree/nbtsort.c
@@ -625,7 +625,7 @@ _bt_blnewpage(uint32 level)
 	_bt_pageinit(page, BLCKSZ);
 
 	/* Initialize BT opaque state */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	opaque->btpo_prev = opaque->btpo_next = P_NONE;
 	opaque->btpo_level = level;
 	opaque->btpo_flags = (level > 0) ? 0 : BTP_LEAF;
@@ -1000,9 +1000,9 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup,
 		Assert((BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) <=
 				IndexRelationGetNumberOfKeyAttributes(wstate->index) &&
 				BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) > 0) ||
-			   P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage)));
+			   P_LEFTMOST(BTPageGetOpaque(opage)));
 		Assert(BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) == 0 ||
-			   !P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage)));
+			   !P_LEFTMOST(BTPageGetOpaque(opage)));
 		BTreeTupleSetDownLink(state->btps_lowkey, oblkno);
 		_bt_buildadd(wstate, state->btps_next, state->btps_lowkey, 0);
 		pfree(state->btps_lowkey);
@@ -1017,8 +1017,8 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup,
 		 * Set the sibling links for both pages.
 		 */
 		{
-			BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(opage);
-			BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(npage);
+			BTPageOpaque oopaque = BTPageGetOpaque(opage);
+			BTPageOpaque nopaque = BTPageGetOpaque(npage);
 
 			oopaque->btpo_next = nblkno;
 			nopaque->btpo_prev = oblkno;
@@ -1125,7 +1125,7 @@ _bt_uppershutdown(BTWriteState *wstate, BTPageState *state)
 		BTPageOpaque opaque;
 
 		blkno = s->btps_blkno;
-		opaque = (BTPageOpaque) PageGetSpecialPointer(s->btps_page);
+		opaque = BTPageGetOpaque(s->btps_page);
 
 		/*
 		 * We have to link the last page on this level to somewhere.
diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c
index c46594e1a20..ee01ceafdac 100644
--- a/src/backend/access/nbtree/nbtsplitloc.c
+++ b/src/backend/access/nbtree/nbtsplitloc.c
@@ -152,7 +152,7 @@ _bt_findsplitloc(Relation rel,
 	SplitPoint	leftpage,
 				rightpage;
 
-	opaque = (BTPageOpaque) PageGetSpecialPointer(origpage);
+	opaque = BTPageGetOpaque(origpage);
 	maxoff = PageGetMaxOffsetNumber(origpage);
 
 	/* Total free space available on a btree page, after fixed overhead */
diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c
index 84164748b3e..96c72fc4324 100644
--- a/src/backend/access/nbtree/nbtutils.c
+++ b/src/backend/access/nbtree/nbtutils.c
@@ -1774,7 +1774,7 @@ _bt_killitems(IndexScanDesc scan)
 		}
 	}
 
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	minoff = P_FIRSTDATAKEY(opaque);
 	maxoff = PageGetMaxOffsetNumber(page);
 
@@ -2474,7 +2474,7 @@ _bt_check_natts(Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum)
 {
 	int16		natts = IndexRelationGetNumberOfAttributes(rel);
 	int16		nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
-	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	BTPageOpaque opaque = BTPageGetOpaque(page);
 	IndexTuple	itup;
 	int			tupnatts;
 
@@ -2662,7 +2662,7 @@ _bt_check_third_page(Relation rel, Relation heap, bool needheaptidspace,
 	 * Internal page insertions cannot fail here, because that would mean that
 	 * an earlier leaf level insertion that should have failed didn't
 	 */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	if (!P_ISLEAF(opaque))
 		elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"",
 			 itemsz, RelationGetRelationName(rel));
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index 611f412ba8a..fba124b9404 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -115,7 +115,7 @@ _bt_restore_meta(XLogReaderState *record, uint8 block_id)
 	md->btm_last_cleanup_num_heap_tuples = -1.0;
 	md->btm_allequalimage = xlrec->allequalimage;
 
-	pageop = (BTPageOpaque) PageGetSpecialPointer(metapg);
+	pageop = BTPageGetOpaque(metapg);
 	pageop->btpo_flags = BTP_META;
 
 	/*
@@ -146,7 +146,7 @@ _bt_clear_incomplete_split(XLogReaderState *record, uint8 block_id)
 	if (XLogReadBufferForRedo(record, block_id, &buf) == BLK_NEEDS_REDO)
 	{
 		Page		page = (Page) BufferGetPage(buf);
-		BTPageOpaque pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+		BTPageOpaque pageop = BTPageGetOpaque(page);
 
 		Assert(P_INCOMPLETE_SPLIT(pageop));
 		pageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT;
@@ -292,7 +292,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record)
 	rpage = (Page) BufferGetPage(rbuf);
 
 	_bt_pageinit(rpage, BufferGetPageSize(rbuf));
-	ropaque = (BTPageOpaque) PageGetSpecialPointer(rpage);
+	ropaque = BTPageGetOpaque(rpage);
 
 	ropaque->btpo_prev = origpagenumber;
 	ropaque->btpo_next = spagenumber;
@@ -317,7 +317,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record)
 		 * same for the right page.
 		 */
 		Page		origpage = (Page) BufferGetPage(buf);
-		BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage);
+		BTPageOpaque oopaque = BTPageGetOpaque(origpage);
 		OffsetNumber off;
 		IndexTuple	newitem = NULL,
 					left_hikey = NULL,
@@ -442,7 +442,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record)
 		if (XLogReadBufferForRedo(record, 2, &sbuf) == BLK_NEEDS_REDO)
 		{
 			Page		spage = (Page) BufferGetPage(sbuf);
-			BTPageOpaque spageop = (BTPageOpaque) PageGetSpecialPointer(spage);
+			BTPageOpaque spageop = BTPageGetOpaque(spage);
 
 			spageop->btpo_prev = rightpagenumber;
 
@@ -473,7 +473,7 @@ btree_xlog_dedup(XLogReaderState *record)
 	{
 		char	   *ptr = XLogRecGetBlockData(record, 0, NULL);
 		Page		page = (Page) BufferGetPage(buf);
-		BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		BTPageOpaque opaque = BTPageGetOpaque(page);
 		OffsetNumber offnum,
 					minoff,
 					maxoff;
@@ -541,7 +541,7 @@ btree_xlog_dedup(XLogReaderState *record)
 
 		if (P_HAS_GARBAGE(opaque))
 		{
-			BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage);
+			BTPageOpaque nopaque = BTPageGetOpaque(newpage);
 
 			nopaque->btpo_flags &= ~BTP_HAS_GARBAGE;
 		}
@@ -639,7 +639,7 @@ btree_xlog_vacuum(XLogReaderState *record)
 		 * Mark the page as not containing any LP_DEAD items --- see comments
 		 * in _bt_delitems_vacuum().
 		 */
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		opaque->btpo_flags &= ~BTP_HAS_GARBAGE;
 
 		PageSetLSN(page, lsn);
@@ -699,7 +699,7 @@ btree_xlog_delete(XLogReaderState *record)
 			PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted);
 
 		/* Mark the page as not containing any LP_DEAD items */
-		opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+		opaque = BTPageGetOpaque(page);
 		opaque->btpo_flags &= ~BTP_HAS_GARBAGE;
 
 		PageSetLSN(page, lsn);
@@ -737,7 +737,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 		BlockNumber rightsib;
 
 		page = (Page) BufferGetPage(buffer);
-		pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+		pageop = BTPageGetOpaque(page);
 
 		poffset = xlrec->poffset;
 
@@ -768,7 +768,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	page = (Page) BufferGetPage(buffer);
 
 	_bt_pageinit(page, BufferGetPageSize(buffer));
-	pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+	pageop = BTPageGetOpaque(page);
 
 	pageop->btpo_prev = xlrec->leftblk;
 	pageop->btpo_next = xlrec->rightblk;
@@ -833,7 +833,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		if (XLogReadBufferForRedo(record, 1, &leftbuf) == BLK_NEEDS_REDO)
 		{
 			page = (Page) BufferGetPage(leftbuf);
-			pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+			pageop = BTPageGetOpaque(page);
 			pageop->btpo_next = rightsib;
 
 			PageSetLSN(page, lsn);
@@ -848,7 +848,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 	page = (Page) BufferGetPage(target);
 
 	_bt_pageinit(page, BufferGetPageSize(target));
-	pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+	pageop = BTPageGetOpaque(page);
 
 	pageop->btpo_prev = leftsib;
 	pageop->btpo_next = rightsib;
@@ -865,7 +865,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 	if (XLogReadBufferForRedo(record, 2, &rightbuf) == BLK_NEEDS_REDO)
 	{
 		page = (Page) BufferGetPage(rightbuf);
-		pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+		pageop = BTPageGetOpaque(page);
 		pageop->btpo_prev = leftsib;
 
 		PageSetLSN(page, lsn);
@@ -906,7 +906,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		page = (Page) BufferGetPage(leafbuf);
 
 		_bt_pageinit(page, BufferGetPageSize(leafbuf));
-		pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+		pageop = BTPageGetOpaque(page);
 
 		pageop->btpo_flags = BTP_HALF_DEAD | BTP_LEAF;
 		pageop->btpo_prev = xlrec->leafleftsib;
@@ -948,7 +948,7 @@ btree_xlog_newroot(XLogReaderState *record)
 	page = (Page) BufferGetPage(buffer);
 
 	_bt_pageinit(page, BufferGetPageSize(buffer));
-	pageop = (BTPageOpaque) PageGetSpecialPointer(page);
+	pageop = BTPageGetOpaque(page);
 
 	pageop->btpo_flags = BTP_ROOT;
 	pageop->btpo_prev = pageop->btpo_next = P_NONE;
@@ -1097,7 +1097,7 @@ btree_mask(char *pagedata, BlockNumber blkno)
 	mask_page_hint_bits(page);
 	mask_unused_space(page);
 
-	maskopaq = (BTPageOpaque) PageGetSpecialPointer(page);
+	maskopaq = BTPageGetOpaque(page);
 
 	if (P_ISLEAF(maskopaq))
 	{
diff --git a/src/include/access/hash.h b/src/include/access/hash.h
index cd7b2a53d8a..da372841c4b 100644
--- a/src/include/access/hash.h
+++ b/src/include/access/hash.h
@@ -85,6 +85,8 @@ typedef struct HashPageOpaqueData
 
 typedef HashPageOpaqueData *HashPageOpaque;
 
+#define HashPageGetOpaque(page) ((HashPageOpaque) PageGetSpecialPointer(page))
+
 #define H_NEEDS_SPLIT_CLEANUP(opaque)	(((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0)
 #define H_BUCKET_BEING_SPLIT(opaque)	(((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0)
 #define H_BUCKET_BEING_POPULATED(opaque)	(((opaque)->hasho_flag & LH_BUCKET_BEING_POPULATED) != 0)
diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h
index 9fec6fb1a8a..93f8267b483 100644
--- a/src/include/access/nbtree.h
+++ b/src/include/access/nbtree.h
@@ -70,6 +70,8 @@ typedef struct BTPageOpaqueData
 
 typedef BTPageOpaqueData *BTPageOpaque;
 
+#define BTPageGetOpaque(page) ((BTPageOpaque) PageGetSpecialPointer(page))
+
 /* Bits defined in btpo_flags */
 #define BTP_LEAF		(1 << 0)	/* leaf page, i.e. not internal page */
 #define BTP_ROOT		(1 << 1)	/* root page (has no parent) */
@@ -241,7 +243,7 @@ BTPageSetDeleted(Page page, FullTransactionId safexid)
 	PageHeader	header;
 	BTDeletedPageData *contents;
 
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	header = ((PageHeader) page);
 
 	opaque->btpo_flags &= ~BTP_HALF_DEAD;
@@ -263,7 +265,7 @@ BTPageGetDeleteXid(Page page)
 
 	/* We only expect to be called with a deleted page */
 	Assert(!PageIsNew(page));
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	Assert(P_ISDELETED(opaque));
 
 	/* pg_upgrade'd deleted page -- must be safe to delete now */
@@ -294,7 +296,7 @@ BTPageIsRecyclable(Page page)
 	Assert(!PageIsNew(page));
 
 	/* Recycling okay iff page is deleted and safexid is old enough */
-	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+	opaque = BTPageGetOpaque(page);
 	if (P_ISDELETED(opaque))
 	{
 		/*