Re: [PATCH 1/2] qnx4: Extract dir entry filename processing into helper

From: kernel test robot
Date: Sat Nov 18 2023 - 10:04:39 EST


Hi Kees,

kernel test robot noticed the following build errors:

[auto build test ERROR on linus/master]
[also build test ERROR on v6.7-rc1 next-20231117]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Kees-Cook/qnx4-Extract-dir-entry-filename-processing-into-helper/20231118-114223
base: linus/master
patch link: https://lore.kernel.org/r/20231118033225.2181299-1-keescook%40chromium.org
patch subject: [PATCH 1/2] qnx4: Extract dir entry filename processing into helper
config: i386-randconfig-011-20231118 (https://download.01.org/0day-ci/archive/20231118/202311182210.gREgIbSb-lkp@xxxxxxxxx/config)
compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231118/202311182210.gREgIbSb-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202311182210.gREgIbSb-lkp@xxxxxxxxx/

All errors (new ones prefixed by >>):

In file included from fs/qnx4/dir.c:16:0:
>> fs/qnx4/qnx4.h:86:51: error: expected ',' before ')' token
offsetof(struct qnx4_link_info, dl_status));
^
fs/qnx4/qnx4.h:88:56: error: expected ',' before ')' token
offsetof(union qnx4_directory_entry, de_status));
^


vim +86 fs/qnx4/qnx4.h

47
48 /*
49 * A qnx4 directory entry is an inode entry or link info
50 * depending on the status field in the last byte. The
51 * first byte is where the name start either way, and a
52 * zero means it's empty.
53 *
54 * Also, due to a bug in gcc, we don't want to use the
55 * real (differently sized) name arrays in the inode and
56 * link entries, but always the 'de_name[]' one in the
57 * fake struct entry.
58 *
59 * See
60 *
61 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578#c6
62 *
63 * for details, but basically gcc will take the size of the
64 * 'name' array from one of the used union entries randomly.
65 *
66 * This use of 'de_name[]' (48 bytes) avoids the false positive
67 * warnings that would happen if gcc decides to use 'inode.di_name'
68 * (16 bytes) even when the pointer and size were to come from
69 * 'link.dl_name' (48 bytes).
70 *
71 * In all cases the actual name pointer itself is the same, it's
72 * only the gcc internal 'what is the size of this field' logic
73 * that can get confused.
74 */
75 union qnx4_directory_entry {
76 struct {
77 const char de_name[48];
78 u8 de_pad[15];
79 u8 de_status;
80 };
81 struct qnx4_inode_entry inode;
82 struct qnx4_link_info link;
83 };
84 /* Make sure the status byte is in the same place for all structs. */
85 _Static_assert(offsetof(struct qnx4_inode_entry, di_status) ==
> 86 offsetof(struct qnx4_link_info, dl_status));
87 _Static_assert(offsetof(struct qnx4_inode_entry, di_status) ==
88 offsetof(union qnx4_directory_entry, de_status));
89

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki