blob: 265e52633b85267f06207d4a9a203475aff0ca04 [file] [log] [blame]
Brad Bishop1a4b7ee2018-12-16 17:11:34 -08001From 2a50366ded329bfb39d387253450c9d5302c3503 Mon Sep 17 00:00:00 2001
2From: Robert Yang <liezhi.yang@windriver.com>
3Date: Tue, 14 Aug 2018 12:22:35 +0100
4Subject: [PATCH] as.c: Improve check for input file matching output file.
5
6When the assembler reports that the input and output are the same, report the
7file names involved, in order to help debugging. Also do not equate two files
8are the same if the have the same inode value but reside on different file
9systems.
10
11Upstream-Status: Backport
12
13Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
14---
15 gas/as.c | 27 ++++++++++++++++++++-------
16 2 files changed, 20 insertions(+), 7 deletions(-)
17
18diff --git a/gas/as.c b/gas/as.c
19index b2a908a..3105d06 100644
20--- a/gas/as.c
21+++ b/gas/as.c
22@@ -1259,14 +1259,27 @@ main (int argc, char ** argv)
23 {
24 struct stat sib;
25
26- if (stat (argv[i], &sib) == 0)
27+ /* Check that the input file and output file are different. */
28+ if (stat (argv[i], &sib) == 0
29+ && sib.st_ino == sob.st_ino
30+ /* POSIX emulating systems may support stat() but if the
31+ underlying file system does not support a file serial number
32+ of some kind then they will return 0 for the inode. So
33+ two files with an inode of 0 may not actually be the same.
34+ On real POSIX systems no ordinary file will ever have an
35+ inode of 0. */
36+ && sib.st_ino != 0
37+ /* Different files may have the same inode number if they
38+ reside on different devices, so check the st_dev field as
39+ well. */
40+ && sib.st_dev == sob.st_dev)
41 {
42- if (sib.st_ino == sob.st_ino && sib.st_ino != 0)
43- {
44- /* Don't let as_fatal remove the output file! */
45- out_file_name = NULL;
46- as_fatal (_("The input and output files must be distinct"));
47- }
48+ const char *saved_out_file_name = out_file_name;
49+
50+ /* Don't let as_fatal remove the output file! */
51+ out_file_name = NULL;
52+ as_fatal (_("The input '%s' and output '%s' files are the same"),
53+ argv[i], saved_out_file_name);
54 }
55 }
56 }
57--
582.7.4
59