Hi Yamada-san, On Sun, Apr 7, 2019 at 12:45 PM Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote: > After cross-compiling the kernel, "make mrproper" should be executed > with the proper ARCH= option. Otherwise, stale objects will remain > under arch/$(SRCARCH)/. > > One bad scenario is like this: > > $ make ARCH=arm defconfig all # cross-compile the kernel for arm > $ make mrproper # mrproper for host-arch (i.e. x86) > $ make ARCH=arm O=build_dir defconfig all > > If you miss ARCH= for mrproper and cross-compile the kernel with O= > and ARCH= options, Kbuild will happily start to build, but may fail > due to stale objects in the srctree. > > If $(srctree)/arch/$(SRCARCH)/include/generated/ exists, let's stop > the out-of-tree build. To detect this, mrproper should clean only > arch/$(SRCARCH)/include/generated/. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > --- > > Makefile | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/Makefile b/Makefile > index 10643c3..17945ce 100644 > --- a/Makefile > +++ b/Makefile > @@ -1091,7 +1091,9 @@ PHONY += prepare archprepare prepare1 prepare3 > prepare3: include/config/kernel.release > ifneq ($(srctree),.) > @$(kecho) ' Using $(srctree) as source for kernel' > - $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \ > + $(Q)if [ -f $(srctree)/.config -o \ > + -d $(srctree)/include/config -o \ > + -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \ > echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \ > echo >&2 " in the '$(srctree)' directory.";\ This took me a bit to find out what was wrong... Usually I don't run "make mrproper", as it removes files I may want to keep (e.g. tags). Hence I ran "git ls-files -o | grep m68k | xargs rm" (I usually build in separate output directories), confirmed with "git ls-files -o" there were no remaining build artefacts, and was surprised to discover I still got the error message above?!? Apparently arch/m68k/include/generated was still present, but as "git ls-files -o" only shows files, not directories, it was not listed. Perhaps the directory checks above can be changed to directory exists _and_ is not empty? Thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds