Dear Piergiorgio,

In message [ref] you wrote:

quoted

quoted

quoted

xmalloc.o dlink.o
sysfs.o: In function `sysfsline':
sysfs.c:(.text+0x2adb): undefined reference to `parse_uuid'
sysfs.c:(.text+0x2aee): undefined reference to `uuid_zero'
sysfs.c:(.text+0x2af5): undefined reference to `uuid_zero'
collect2: error: ld returned 1 exit status
Makefile:220: recipe for target 'raid6check' failed
make: *** [raid6check] Error 1

I cannot see this problem.
I could compile without issue.
Maybe some library is missing somewhere,
but I'm not sure where.

Do you try with the fastest mdadm tree? But could be environment issue ...

I'm using Fedora, so I downloaded
the .srpm package, installed, enabled
raid6check, patched and rebuild...

Fedora 32 is still at mdadm-4.1 (Mon Oct 1 14:27:52 2018), but it
seems the significant change was introduced bu commit b06815989
"mdadm: load default sysfs attributes after assemblation" (Wed Jul 10
13:38:53 2019).

If you try to build top of tree you should see the problem, too
[and the -Werror issue I mentioned before, which is also fixed
in Fedora by local distro patches.]

Best regards,

Wolfgang Denk

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