diff --git a/src/backend/storage/ipc/shmem.c b/src/backend/storage/ipc/shmem.c
index 250e312..78f15f0 100644
--- a/src/backend/storage/ipc/shmem.c
+++ b/src/backend/storage/ipc/shmem.c
@@ -170,29 +170,26 @@ ShmemAlloc(Size size)
 	Size		newFree;
 	void	   *newSpace;
 
-	/* use volatile pointer to prevent code rearrangement */
-	volatile PGShmemHeader *shmemseghdr = ShmemSegHdr;
-
 	/*
 	 * ensure all space is adequately aligned.
 	 */
 	size = MAXALIGN(size);
 
-	Assert(shmemseghdr != NULL);
+	Assert(ShmemSegHdr != NULL);
 
 	SpinLockAcquire(ShmemLock);
 
-	newStart = shmemseghdr->freeoffset;
+	newStart = ShmemSegHdr->freeoffset;
 
 	/* extra alignment for large requests, since they are probably buffers */
 	if (size >= BLCKSZ)
 		newStart = BUFFERALIGN(newStart);
 
 	newFree = newStart + size;
-	if (newFree <= shmemseghdr->totalsize)
+	if (newFree <= ShmemSegHdr->totalsize)
 	{
 		newSpace = (void *) ((char *) ShmemBase + newStart);
-		shmemseghdr->freeoffset = newFree;
+		ShmemSegHdr->freeoffset = newFree;
 	}
 	else
 		newSpace = NULL;
diff --git a/src/backend/storage/ipc/sinvaladt.c b/src/backend/storage/ipc/sinvaladt.c
index a2fde89..3cc15e0 100644
--- a/src/backend/storage/ipc/sinvaladt.c
+++ b/src/backend/storage/ipc/sinvaladt.c
@@ -485,14 +485,9 @@ SIInsertDataEntries(const SharedInvalidationMessage *data, int n)
 		}
 
 		/* Update current value of maxMsgNum using spinlock */
-		{
-			/* use volatile pointer to prevent code rearrangement */
-			volatile SISeg *vsegP = segP;
-
-			SpinLockAcquire(&vsegP->msgnumLock);
-			vsegP->maxMsgNum = max;
-			SpinLockRelease(&vsegP->msgnumLock);
-		}
+		SpinLockAcquire(&segP->msgnumLock);
+		segP->maxMsgNum = max;
+		SpinLockRelease(&segP->msgnumLock);
 
 		/*
 		 * Now that the maxMsgNum change is globally visible, we give everyone
@@ -579,14 +574,9 @@ SIGetDataEntries(SharedInvalidationMessage *data, int datasize)
 	stateP->hasMessages = false;
 
 	/* Fetch current value of maxMsgNum using spinlock */
-	{
-		/* use volatile pointer to prevent code rearrangement */
-		volatile SISeg *vsegP = segP;
-
-		SpinLockAcquire(&vsegP->msgnumLock);
-		max = vsegP->maxMsgNum;
-		SpinLockRelease(&vsegP->msgnumLock);
-	}
+	SpinLockAcquire(&segP->msgnumLock);
+	max = segP->maxMsgNum;
+	SpinLockRelease(&segP->msgnumLock);
 
 	if (stateP->resetState)
 	{