kbuild: fix infinite make recursion
authorSam Ravnborg <sam@neptun.(none)>
Wed, 26 Sep 2007 17:38:44 +0000 (19:38 +0200)
committerSam Ravnborg <sam@neptun.(none)>
Fri, 12 Oct 2007 19:15:32 +0000 (21:15 +0200)
commit4f1127e204377cbd2a56d112d323466f668e8334
tree8d73e1d7bd0e4a728f7896b766f6ce596bd8e0b2
parenta67cb1319f53fa68012a23d6ca45279c6bc627f8
kbuild: fix infinite make recursion

Jan Engelhardt <jengelh@computergmbh.de> reported:
You can cause a recursion in kbuild/make with the following:

make O=$PWD kernel/time.o
make mrproper

Of course no one would use O=$PWD (that's just the testcase),
but this happened too often:

/ws/linux/linux-2.6.23$ make O=/ws/linux/linux-2.6.23 kernel/time.o
(Oops - should have been O=/ws/linux/obj-2.6.23!)

Fixed by an explicit test for this case - we error
out if output directory and source directory are the same.

Tested-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Makefile