Use ssize_t where signed results can happen

Noted by Alexander Korotkov

diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index d1dc046c97ce75cd30bd5c200f352a3396bc321b..b0b3d435c36d3191ba1c711176a5a15a8ddba752 100644 (file)
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -432,7 +432,7 @@ tar_write_padding_data(TarMethodFile * f, size_t bytes)
    {
        size_t      bytestowrite = bytesleft > XLOG_BLCKSZ ? XLOG_BLCKSZ : bytesleft;
 
-       size_t      r = tar_write(f, zerobuf, bytestowrite);
+       ssize_t     r = tar_write(f, zerobuf, bytestowrite);
 
        if (r < 0)
            return false;