openSUSE Tumbleweed is in the progress of upgrading to GNU Make 4.3. There are
a few documented incompatibilities:

>+  * WARNING: Backward-incompatibility!
>+    Number signs (#) appearing inside a macro reference or function
>+    invocation no longer introduce comments and should not be escaped with
>+    backslashes
>+  * WARNING: Backward-incompatibility!
>+    Previously appending using '+=' to an empty variable would result in a
>+    value starting with a space
>+  * NOTE: Deprecated behavior.
>+    Contrary to the documentation, suffix rules with prerequisites are being
>+    treated BOTH as simple targets AND as pattern rules

AppArmor is about the only package left (in the rings) that is not building
successful with Make 4.3:

https://build.opensuse.org/package/live_build_log/openSUSE:Factory:Staging:O/apparmor/standard/x86_64