From: Paul Eggert <eggert@cs.ucla.edu>
Date: Fri, 7 Jun 2019 23:39:22 +0000 (-0700)
Subject: Fix minor ssize_t / ptrdiff_t confusion
X-Git-Tag: emacs-27.0.90~2666
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=8553af84db8b25918da8f5138dcc34601e3df47e;p=emacs.git

Fix minor ssize_t / ptrdiff_t confusion

* src/fileio.c (Fcopy_file): This limit is because of ssize_t,
so use TYPE_MAXIMUM (ssize_t) not PTRDIFF_MAX.
---

diff --git a/src/fileio.c b/src/fileio.c
index f7376ce74fe..b141f568d70 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2125,7 +2125,8 @@ permissions.  */)
 	  /* Copy at most COPY_MAX bytes at a time; this is min
 	     (PTRDIFF_MAX, SIZE_MAX) truncated to a value that is
 	     surely aligned well.  */
-	  ptrdiff_t copy_max = min (PTRDIFF_MAX, SIZE_MAX) >> 30 << 30;
+	  ssize_t ssize_max = TYPE_MAXIMUM (ssize_t);
+	  ptrdiff_t copy_max = min (ssize_max, SIZE_MAX) >> 30 << 30;
 	  off_t intail = insize - newsize;
 	  ptrdiff_t len = min (intail, copy_max);
 	  copied = copy_file_range (ifd, NULL, ofd, NULL, len, 0);