single target builds are broken

From: Vegard Nossum
Date: Tue Mar 31 2020 - 05:16:45 EST



Hi,

I often run 'make foo/bar.o' as part of my workflow, even when bar.o is
not specified in any kernel makefile, and this has worked just fine for
years.

This is broken after commit 394053f4a4b3e3eeeaa67b67fc886a9a75bd9e4d
(kbuild: make single targets work more correctly) and just gives an error:

$ make kernel/test.o
CALL scripts/checksyscalls.sh
CALL scripts/atomic/check-atomics.sh
DESCEND objtool
make[2]: *** No rule to make target 'kernel/test.o'. Stop.
scripts/Makefile.build:502: recipe for target '__build' failed
make[1]: *** [__build] Error 2
Makefile:1670: recipe for target 'kernel' failed
make: *** [kernel] Error 2

For top-level objects (e.g. 'make bar.o') the situation is even worse,
since make exits with status 0 without building anything :-/

Is there any chance we can get this back? It was super useful for me.


Vegard