[PATCH] sstate: Fail on file systems without hard link support

[Michael Arndt <michael@rndt.dev>]

The sstate can only work reliably when the file system has support for hard
links. Previously this error was silenced, now the build fails and the user is
informed about the problem.

Signed-off-by: Michael Arndt <michael@rndt.dev>
CC: Richard Purdie <richard.purdie@linuxfoundation.org>
---
 meta/classes-global/sstate.bbclass | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/meta/classes-global/sstate.bbclass b/meta/classes-global/sstate.bbclass
index 88449d19c7..1d41d9bc20 100644
--- a/meta/classes-global/sstate.bbclass
+++ b/meta/classes-global/sstate.bbclass
@@ -787,6 +787,7 @@ sstate_task_postfunc[dirs] = "${WORKDIR}"
 # and renamed in place once created.
 python sstate_create_and_sign_package () {
     from pathlib import Path
+    import errno
 
     # Best effort touch
     def touch(file):
@@ -806,6 +807,9 @@ python sstate_create_and_sign_package () {
             else:
                 os.link(src, dst)
             return True
+        except OSError as e:
+            if e.errno == errno.ENOSYS:
+                bb.fatal("sstate is only supported on file systems with hard link support: %s" % e)
         except:
             pass