The build of kselftests fails if relative path is specified through KBUILD_OUTPUT or O=<path> method. BUILD variable is used to determine the path of the output objects. When make is run from other directories with relative paths, the exact path of the build objects is ambiguous and build fails. make[1]: Entering directory '/home/usama/repos/kernel/linux_mainline2/tools/testing/selftests/alsa' gcc mixer-test.c -L/usr/lib/x86_64-linux-gnu -lasound -o build/kselftest/alsa/mixer-test /usr/bin/ld: cannot open output file build/kselftest/alsa/mixer-test Set the BUILD variable to the absolute path of the output directory. Make the logic readable and easy to follow. Use spaces instead of tabs for indentation as if with tab indentation is considered recipe in make. Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx> --- tools/testing/selftests/Makefile | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index d08fe4cfe811..a7b63860b7bc 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -114,19 +114,27 @@ ifdef building_out_of_srctree override LDFLAGS = endif -ifneq ($(O),) - BUILD := $(O)/kselftest +top_srcdir ?= ../../.. + +ifeq ("$(origin O)", "command line") + KBUILD_OUTPUT := $(O) +endif + +ifneq ($(KBUILD_OUTPUT),) + # Make's built-in functions such as $(abspath ...), $(realpath ...) cannot + # expand a shell special character '~'. We use a somewhat tedious way here. + abs_objtree := $(shell cd $(top_srcdir) && mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd) + $(if $(abs_objtree),, \ + $(error failed to create output directory "$(KBUILD_OUTPUT)")) + # $(realpath ...) resolves symlinks + abs_objtree := $(realpath $(abs_objtree)) + BUILD := $(abs_objtree)/kselftest else - ifneq ($(KBUILD_OUTPUT),) - BUILD := $(KBUILD_OUTPUT)/kselftest - else - BUILD := $(shell pwd) - DEFAULT_INSTALL_HDR_PATH := 1 - endif + BUILD := $(CURDIR) + DEFAULT_INSTALL_HDR_PATH := 1 endif # Prepare for headers install -top_srcdir ?= ../../.. include $(top_srcdir)/scripts/subarch.include ARCH ?= $(SUBARCH) export KSFT_KHDR_INSTALL_DONE := 1 -- 2.30.2