| Message ID | 20240527213641.299458-1-jhubbard@nvidia.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] selftests/net: suppress clang's "variable-sized type not at the end" warning | expand |
On Mon, May 27, 2024 at 02:36:41PM -0700, John Hubbard wrote: > When building with clang, via: > > make LLVM=1 -C tools/testing/selftest > > ...clang warns that "a variable sized type not at the end of a struct or > class is a GNU extension". > > These cases are not easily changed, because they involve structs that > are part of the API. Fortunately, however, the tests seem to be doing > just fine (specifically, neither affected test runs any differently with > gcc vs. clang builds, on my test system) regardless of the warning. So, > all the warning is doing is preventing a clean build of selftests/net. > > Fix this by suppressing this particular clang warning for the > selftests/net suite. > > Signed-off-by: John Hubbard <jhubbard@nvidia.com> > --- > > Changes since the first version: > > 1) Rebased onto Linux 6.10-rc1 > > thanks, > John Hubbard > > > tools/testing/selftests/net/Makefile | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile > index bd01e4a0be2c..9a3b766c8781 100644 > --- a/tools/testing/selftests/net/Makefile > +++ b/tools/testing/selftests/net/Makefile > @@ -6,6 +6,10 @@ CFLAGS += -I../../../../usr/include/ $(KHDR_INCLUDES) > # Additional include paths needed by kselftest.h > CFLAGS += -I../ > > +ifneq ($(LLVM),) > + CFLAGS += -Wno-gnu-variable-sized-type-not-at-end For what it's worth, the main kernel has -Wno-gnu because there is little point in warning about the use of GNU extensions when building with '-std=gnu...'. It may be worth doing this anywhere that uses a GNU standard in the selftests but I guess it depends on how noisy things are. > +endif > + > TEST_PROGS := run_netsocktests run_afpackettests test_bpf.sh netdevice.sh \ > rtnetlink.sh xfrm_policy.sh test_blackhole_dev.sh > TEST_PROGS += fib_tests.sh fib-onlink-tests.sh pmtu.sh udpgso.sh ip_defrag.sh > > base-commit: 2bfcfd584ff5ccc8bb7acde19b42570414bf880b > -- > 2.45.1 > >
On 5/28/24 1:39 PM, Nathan Chancellor wrote: > On Mon, May 27, 2024 at 02:36:41PM -0700, John Hubbard wrote: ... >> diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile >> index bd01e4a0be2c..9a3b766c8781 100644 >> --- a/tools/testing/selftests/net/Makefile >> +++ b/tools/testing/selftests/net/Makefile >> @@ -6,6 +6,10 @@ CFLAGS += -I../../../../usr/include/ $(KHDR_INCLUDES) >> # Additional include paths needed by kselftest.h >> CFLAGS += -I../ >> >> +ifneq ($(LLVM),) >> + CFLAGS += -Wno-gnu-variable-sized-type-not-at-end > > For what it's worth, the main kernel has -Wno-gnu because there is > little point in warning about the use of GNU extensions when building > with '-std=gnu...'. It may be worth doing this anywhere that uses a GNU > standard in the selftests but I guess it depends on how noisy things > are. I think there might be one or two other cases like this that I haven't gotten around to, so yes you are right, this probably should be moved into lib.mk instead. I'll do that in a v3. > >> +endif >> + >> TEST_PROGS := run_netsocktests run_afpackettests test_bpf.sh netdevice.sh \ >> rtnetlink.sh xfrm_policy.sh test_blackhole_dev.sh >> TEST_PROGS += fib_tests.sh fib-onlink-tests.sh pmtu.sh udpgso.sh ip_defrag.sh >> >> base-commit: 2bfcfd584ff5ccc8bb7acde19b42570414bf880b >> -- >> 2.45.1 >> >> thanks,
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index bd01e4a0be2c..9a3b766c8781 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -6,6 +6,10 @@ CFLAGS += -I../../../../usr/include/ $(KHDR_INCLUDES) # Additional include paths needed by kselftest.h CFLAGS += -I../ +ifneq ($(LLVM),) + CFLAGS += -Wno-gnu-variable-sized-type-not-at-end +endif + TEST_PROGS := run_netsocktests run_afpackettests test_bpf.sh netdevice.sh \ rtnetlink.sh xfrm_policy.sh test_blackhole_dev.sh TEST_PROGS += fib_tests.sh fib-onlink-tests.sh pmtu.sh udpgso.sh ip_defrag.sh
When building with clang, via: make LLVM=1 -C tools/testing/selftest ...clang warns that "a variable sized type not at the end of a struct or class is a GNU extension". These cases are not easily changed, because they involve structs that are part of the API. Fortunately, however, the tests seem to be doing just fine (specifically, neither affected test runs any differently with gcc vs. clang builds, on my test system) regardless of the warning. So, all the warning is doing is preventing a clean build of selftests/net. Fix this by suppressing this particular clang warning for the selftests/net suite. Signed-off-by: John Hubbard <jhubbard@nvidia.com> --- Changes since the first version: 1) Rebased onto Linux 6.10-rc1 thanks, John Hubbard tools/testing/selftests/net/Makefile | 4 ++++ 1 file changed, 4 insertions(+) base-commit: 2bfcfd584ff5ccc8bb7acde19b42570414bf880b