With clang compiler:
make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel
make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1
Some linker flags are not used/effective for some binaries and
we have warnings like:
warning: -lelf: 'linker' input unused [-Wunused-command-line-argument]
We also have warnings like:
.../selftests/bpf/prog_tests/ns_current_pid_tgid.c:74:57: note: treat the string as an argument to avoid this
if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", strerror(errno)))
^
"%s",
.../selftests/bpf/test_progs.h:129:35: note: expanded from macro 'CHECK'
_CHECK(condition, tag, duration, format)
^
.../selftests/bpf/test_progs.h:108:21: note: expanded from macro '_CHECK'
fprintf(stdout, ##format); \
^
The first warning can be silenced with clang option -Wno-unused-command-line-argument,
and the second with -Wno-format-security. Further, gcc does not support the option
-Wno-unused-command-line-argument. Since the warning only happens with clang
compiler, these two options are enabled only when clang compiler is used and this
fixed the above warnings.
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
tools/testing/selftests/bpf/Makefile | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index bbd61cc3889b..ef7078756c8a 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -28,6 +28,11 @@ CFLAGS += -g -Og -rdynamic -Wall $(GENFLAGS) $(SAN_CFLAGS) \
-Dbpf_load_program=bpf_test_load_program
LDLIBS += -lcap -lelf -lz -lrt -lpthread
+# Silence some warnings when compiled with clang
+ifneq ($(LLVM),)
+CFLAGS += -Wno-unused-command-line-argument -Wno-format-security
+endif
+
# Order correspond to 'make run_tests' order
TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
test_verifier_log test_dev_cgroup \
--
2.30.2
