On Tue, Mar 31, 2020 at 6:16 PM Vegard Nossum <vegard.nossum@xxxxxxxxxx> wrote: > > > 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 This is intentional to make the single target builds work in the same manner as the normal builds. The necessary CONFIG dependency must be met. obj-$(CONFIG_FOO) += foo.o foo.o can be built only when CONFIG_FOO is y/m. > For top-level objects (e.g. 'make bar.o') the situation is even worse, > since make exits with status 0 without building anything :-/ There is no .c or .S file at the top-level of the kernel source tree. 'make bar.o' never happens. > Is there any chance we can get this back? It was super useful for me. What you want is "Let's build whatever", right? No, please add 'obj-y += test.o' if you want to test your local file. -- Best Regards Masahiro Yamada
