From: Andrew Delgadillo adelg@google.com

clang complains about using -o when one specifies header files on the commandline. An example can be seen when building the futex selftests:

$ make -C tools/testing/selftests TARGETS=futex clang -Wall -g -O2 -Wall -D_GNU_SOURCE -pthread -I../include \ -I../../ -I../../../../../usr/include/ -I/kselftest/usr/include \ futex_wait_timeout.c ../include/futextest.h ../include/atomic.h \ ../include/logging.h -lpthread -lrt -o \ tools/testing/selftests/futex/functional/futex_wait_timeout clang: error: cannot specify -o when generating multiple output files

To fix this, instead of specifying the headers explicitliy, we include (with -I) their directories. Note that -I does not work with files, only directories [1,2]

There are still errors when building with clang, but this patch does a way with one class of those errors.

Tested: No new errors when building with LLVM=0/1. In fact, clang no longer errors out with "cannot specify -o ..." anymore.

[1] https://gcc.gnu.org/onlinedocs/gcc-11.2.0/gcc/Directory-Options.html#Directo... [2] https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-i...

Suggested-by: gthelen@google.com Signed-off-by: Andrew Delgadillo adelg@google.com --- Changes since v1: - Instead of removing the headers from the cmdline altogether, include their directories. - Add more detail to the tested tag. - Add missing Suggested-By tag from original patch.

tools/testing/selftests/filesystems/binderfs/Makefile | 4 ++-- tools/testing/selftests/lib.mk | 5 ++++- tools/testing/selftests/x86/Makefile | 4 ++-- 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/filesystems/binderfs/Makefile b/tools/testing/selftests/filesystems/binderfs/Makefile index 8af25ae96049..e2f09acb15b4 100644 --- a/tools/testing/selftests/filesystems/binderfs/Makefile +++ b/tools/testing/selftests/filesystems/binderfs/Makefile @@ -1,8 +1,8 @@ # SPDX-License-Identifier: GPL-2.0

-CFLAGS += -I../../../../../usr/include/ -pthread +CFLAGS += -I../../../../../usr/include/ -I$(selfdir) -pthread TEST_GEN_PROGS := binderfs_test

-binderfs_test: binderfs_test.c ../../kselftest.h ../../kselftest_harness.h +binderfs_test: binderfs_test.c

include ../../lib.mk diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk index fa2ac0e56b43..0edf2a421771 100644 --- a/tools/testing/selftests/lib.mk +++ b/tools/testing/selftests/lib.mk @@ -137,12 +137,15 @@ COMPILE.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c LINK.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) endif

+ # Selftest makefiles can override those targets by setting # OVERRIDE_TARGETS = 1. ifeq ($(OVERRIDE_TARGETS),) LOCAL_HDRS := $(selfdir)/kselftest_harness.h $(selfdir)/kselftest.h $(OUTPUT)/%:%.c $(LOCAL_HDRS) - $(LINK.c) $(filter-out $(LOCAL_HDRS),$^) $(LDLIBS) -o $@ + $(LINK.c) $(filter-out %.h,$^) \ + $(addprefix -I,$(dir $(filter %.h,$^))) \ + $(LDLIBS) -o $@

$(OUTPUT)/%.o:%.S $(COMPILE.S) $^ -o $@ diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index b4142cd1c5c2..f794d431f289 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -72,10 +72,10 @@ all_64: $(BINARIES_64) EXTRA_CLEAN := $(BINARIES_32) $(BINARIES_64)

$(BINARIES_32): $(OUTPUT)/%_32: %.c helpers.h - $(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl -lm + $(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $(filter-out %.h,$^) $(addprefix -I,$(dir $(filter %.h,$^))) -lrt -ldl -lm

$(BINARIES_64): $(OUTPUT)/%_64: %.c helpers.h - $(CC) -m64 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl + $(CC) -m64 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $(filter-out %.h,$^) $(addprefix -I,$(dir $(filter %.h,$^))) -lrt -ldl

# x86_64 users should be encouraged to install 32-bit libraries ifeq ($(CAN_BUILD_I386)$(CAN_BUILD_X86_64),01)