Currently if you build with O=... the rseq tests don't build: $ make O=$PWD/output -C tools/testing/selftests/ TARGETS=rseq make: Entering directory '/linux/tools/testing/selftests' ... make[1]: Entering directory '/linux/tools/testing/selftests/rseq' gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ -shared -fPIC rseq.c -lpthread -o /linux/output/rseq/librseq.so gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ basic_test.c -lpthread -lrseq -o /linux/output/rseq/basic_test /usr/bin/ld: cannot find -lrseq collect2: error: ld returned 1 exit status This is because the library search path points to the source directory, not the output. We can fix it by changing the library search path to $(OUTPUT). Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> --- This works in all cases. With O= set: $ make O=$PWD/output -C tools/testing/selftests/ TARGETS=rseq ... make[1]: Entering directory '/linux/tools/testing/selftests/rseq' gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/output/rseq -Wl,-rpath=./ basic_test.c -lpthread -lrseq -o /linux/output/rseq/basic_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/output/rseq -Wl,-rpath=./ basic_percpu_ops_test.c -lpthread -lrseq -o /linux/output/rseq/basic_percpu_ops_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/output/rseq -Wl,-rpath=./ param_test.c -lpthread -lrseq -o /linux/output/rseq/param_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/output/rseq -Wl,-rpath=./ -DBENCHMARK param_test.c -lpthread -lrseq -o /linux/output/rseq/param_test_benchmark gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/output/rseq -Wl,-rpath=./ -DRSEQ_COMPARE_TWICE param_test.c -lpthread -lrseq -o /linux/output/rseq/param_test_compare_twice make[1]: Leaving directory '/linux/tools/testing/selftests/rseq' make: Leaving directory '/linux/tools/testing/selftests' And also without, in which case the selftest makefiles set OUTPUT to the full path of the source directory: $ make -C tools/testing/selftests/ TARGETS=rseq ... make[1]: Entering directory '/linux/tools/testing/selftests/rseq' gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -shared -fPIC rseq.c -lpthread -o /linux/tools/testing/selftests/rseq/librseq.so gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ basic_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/basic_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ basic_percpu_ops_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/basic_percpu_ops_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -DBENCHMARK param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test_benchmark gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -DRSEQ_COMPARE_TWICE param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test_compare_twice make[1]: Leaving directory '/linux/tools/testing/selftests/rseq' make: Leaving directory '/linux/tools/testing/selftests' And finally, it also works if you build directly in the rseq directory, eg: $ cd tools/testing/selftests/rseq $ make gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -shared -fPIC rseq.c -lpthread -o /linux/tools/testing/selftests/rseq/librseq.so gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ basic_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/basic_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ basic_percpu_ops_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/basic_percpu_ops_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -DBENCHMARK param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test_benchmark gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L/linux/tools/testing/selftests/rseq -Wl,-rpath=./ -DRSEQ_COMPARE_TWICE param_test.c -lpthread -lrseq -o /linux/tools/testing/selftests/rseq/param_test_compare_twice --- tools/testing/selftests/rseq/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile index d6469535630a..708c1b345245 100644 --- a/tools/testing/selftests/rseq/Makefile +++ b/tools/testing/selftests/rseq/Makefile @@ -4,7 +4,7 @@ ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) CLANG_FLAGS += -no-integrated-as endif -CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ \ +CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L$(OUTPUT) -Wl,-rpath=./ \ $(CLANG_FLAGS) LDLIBS += -lpthread base-commit: 11a48a5a18c63fd7621bb050228cebf13566e4d8 -- 2.21.1