diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 1e9019156a..1264849883 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -2280,7 +2280,7 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
 			char	   *from;
 			Size		nbytes;
 			Size		nleft;
-			int			written;
+			ssize_t		written;
 			instr_time	start;
 
 			/* OK to write the page(s) */
diff --git a/src/backend/backup/basebackup.c b/src/backend/backup/basebackup.c
index 5ee9628422..84246739ae 100644
--- a/src/backend/backup/basebackup.c
+++ b/src/backend/backup/basebackup.c
@@ -117,8 +117,8 @@ static void perform_base_backup(basebackup_options *opt, bbsink *sink,
 								IncrementalBackupInfo *ib);
 static void parse_basebackup_options(List *options, basebackup_options *opt);
 static int	compareWalFileNames(const ListCell *a, const ListCell *b);
-static int	basebackup_read_file(int fd, char *buf, size_t nbytes, off_t offset,
-								 const char *filename, bool partial_read_ok);
+static ssize_t basebackup_read_file(int fd, char *buf, size_t nbytes, off_t offset,
+									const char *filename, bool partial_read_ok);
 
 /* Was the backup currently in-progress initiated in recovery mode? */
 static bool backup_started_in_recovery = false;
@@ -525,7 +525,7 @@ perform_base_backup(basebackup_options *opt, bbsink *sink,
 		{
 			char	   *walFileName = (char *) lfirst(lc);
 			int			fd;
-			size_t		cnt;
+			ssize_t		cnt;
 			pgoff_t		len = 0;
 
 			snprintf(pathbuf, MAXPGPATH, XLOGDIR "/%s", walFileName);
@@ -2079,11 +2079,11 @@ convert_link_to_directory(const char *pathbuf, struct stat *statbuf)
  *
  * Returns the number of bytes read.
  */
-static int
+static ssize_t
 basebackup_read_file(int fd, char *buf, size_t nbytes, off_t offset,
 					 const char *filename, bool partial_read_ok)
 {
-	int			rc;
+	ssize_t		rc;
 
 	pgstat_report_wait_start(WAIT_EVENT_BASEBACKUP_READ);
 	rc = pg_pread(fd, buf, nbytes, offset);
@@ -2096,7 +2096,7 @@ basebackup_read_file(int fd, char *buf, size_t nbytes, off_t offset,
 	if (!partial_read_ok && rc > 0 && rc != nbytes)
 		ereport(ERROR,
 				(errcode_for_file_access(),
-				 errmsg("could not read file \"%s\": read %d of %zu",
+				 errmsg("could not read file \"%s\": read %zd of %zu",
 						filename, rc, nbytes)));
 
 	return rc;
diff --git a/src/bin/pg_combinebackup/reconstruct.c b/src/bin/pg_combinebackup/reconstruct.c
index 6decdd8934..874e6cd150 100644
--- a/src/bin/pg_combinebackup/reconstruct.c
+++ b/src/bin/pg_combinebackup/reconstruct.c
@@ -504,7 +504,7 @@ make_rfile(char *filename, bool missing_ok)
 static void
 read_bytes(rfile *rf, void *buffer, unsigned length)
 {
-	unsigned	rb = read(rf->fd, buffer, length);
+	int			rb = read(rf->fd, buffer, length);
 
 	if (rb != length)
 	{
@@ -512,7 +512,7 @@ read_bytes(rfile *rf, void *buffer, unsigned length)
 			pg_fatal("could not read file \"%s\": %m", rf->filename);
 		else
 			pg_fatal("could not read file \"%s\": read only %d of %d bytes",
-					 rf->filename, (int) rb, length);
+					 rf->filename, rb, length);
 	}
 }
 
@@ -614,7 +614,7 @@ write_reconstructed_file(char *input_filename,
 	{
 		uint8		buffer[BLCKSZ];
 		rfile	   *s = sourcemap[i];
-		unsigned	wb;
+		int			wb;
 
 		/* Update accounting information. */
 		if (s == NULL)
@@ -641,7 +641,7 @@ write_reconstructed_file(char *input_filename,
 		}
 		else
 		{
-			unsigned	rb;
+			int			rb;
 
 			/* Read the block from the correct source, except if dry-run. */
 			rb = pg_pread(s->fd, buffer, BLCKSZ, offsetmap[i]);
@@ -650,9 +650,9 @@ write_reconstructed_file(char *input_filename,
 				if (rb < 0)
 					pg_fatal("could not read file \"%s\": %m", s->filename);
 				else
-					pg_fatal("could not read file \"%s\": read only %d of %d bytes at offset %u",
-							 s->filename, (int) rb, BLCKSZ,
-							 (unsigned) offsetmap[i]);
+					pg_fatal("could not read file \"%s\": read only %d of %d bytes at offset %llu",
+							 s->filename, rb, BLCKSZ,
+							 (unsigned long long) offsetmap[i]);
 			}
 		}
 
@@ -663,7 +663,7 @@ write_reconstructed_file(char *input_filename,
 				pg_fatal("could not write file \"%s\": %m", output_filename);
 			else
 				pg_fatal("could not write file \"%s\": wrote only %d of %d bytes",
-						 output_filename, (int) wb, BLCKSZ);
+						 output_filename, wb, BLCKSZ);
 		}
 
 		/* Update the checksum computation. */