On Sun, Apr 11, 2021 at 7:20 PM Yonghong Song <yhs@xxxxxx> wrote: > > > > On 4/11/21 3:47 AM, Sedat Dilek wrote: > > On Sat, Apr 10, 2021 at 6:49 PM Yonghong Song <yhs@xxxxxx> wrote: > >> > >> With clang compiler: > >> make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel > >> make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 > >> the test_cpp build failed due to the failure: > >> warning: treating 'c-header' input as 'c++-header' when in C++ mode, this behavior is deprecated [-Wdeprecated] > >> clang-13: warning: cannot specify -o when generating multiple output files > >> > >> test_cpp compilation flag looks like: > >> clang++ -g -Og -rdynamic -Wall -I<...> ... \ > >> -Dbpf_prog_load=bpf_prog_test_load -Dbpf_load_program=bpf_test_load_program \ > >> test_cpp.cpp <...>/test_core_extern.skel.h <...>/libbpf.a <...>/test_stub.o \ > >> -lcap -lelf -lz -lrt -lpthread -o <...>/test_cpp > >> > >> The clang++ compiler complains the header file in the command line. > >> Let us remove the header file from the command line which is not intended > >> any way, and this fixed the problem. > >> > >> Signed-off-by: Yonghong Song <yhs@xxxxxx> > >> --- > >> tools/testing/selftests/bpf/Makefile | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile > >> index 6448c626498f..bbd61cc3889b 100644 > >> --- a/tools/testing/selftests/bpf/Makefile > >> +++ b/tools/testing/selftests/bpf/Makefile > >> @@ -481,7 +481,7 @@ $(OUTPUT)/test_verifier: test_verifier.c verifier/tests.h $(BPFOBJ) | $(OUTPUT) > >> # Make sure we are able to include and link libbpf against c++. > >> $(OUTPUT)/test_cpp: test_cpp.cpp $(OUTPUT)/test_core_extern.skel.h $(BPFOBJ) > >> $(call msg,CXX,,$@) > >> - $(Q)$(CXX) $(CFLAGS) $^ $(LDLIBS) -o $@ > >> + $(Q)$(CXX) $(CFLAGS) test_cpp.cpp $(BPFOBJ) $(LDLIBS) -o $@ > >> > >> # Benchmark runner > >> $(OUTPUT)/bench_%.o: benchs/bench_%.c bench.h > >> -- > >> 2.30.2 > >> > > > > NOTE: bpf-next might be different from my build-environment. > > > > Yonghong, can you please re-test by adding explicitly CXX=g++ to your make line? > > > > Here I have: > > > > $ grep test_cpp make-log_tools-testing-selftests-bpf_clang_clang++.txt > > 1907:clang++ -g -rdynamic -Wall -O2 -DHAVE_GENHDR > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/include > > -I/home/dileks/src/linux-kernel/git/include/generated > > -I/home/dileks/src/linux-kernel/git/tools/lib > > -I/home/dileks/src/linux-kernel/git/tools/include > > -I/home/dileks/src/linux-kernel/git/tools/include/uapi > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -Wno-unused-command-line-argument -Wno-format-security > > -Dbpf_prog_load=bpf_prog_test_load > > -Dbpf_load_program=bpf_test_load_program test_cpp.cpp > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a > > -lcap -lelf -lz -lrt -lpthread -o > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_cpp > > > > This clang++ line does not include <...>/test_core_extern.skel.h ^^^ > > > > $ grep test_core_extern.skel.h > > make-log_tools-testing-selftests-bpf_clang_clang++.txt > > 704:/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/sbin/bpftool > > gen skeleton /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_co > > re_extern.o > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_core_extern.skel.h > > 1592:/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/sbin/bpftool > > gen skeleton /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/no_alu > > 32/test_core_extern.o > > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/no_alu32/test_core_extern.skel.h > > > > Checking test_cpp: > > > > $ /opt/llvm-toolchain/bin/llvm-objdump-12 -Dr test_cpp | grep extern > > 0000000000417e50 <cmp_externs>: > > 417e54: 75 22 jne 0x417e78 <cmp_externs+0x28> > > 417e59: 75 10 jne 0x417e6b <cmp_externs+0x1b> > > 417e61: 75 21 jne 0x417e84 <cmp_externs+0x34> > > 417e69: 75 1e jne 0x417e89 <cmp_externs+0x39> > > 417e87: eb f2 jmp 0x417e7b <cmp_externs+0x2b> > > 417e8c: eb ed jmp 0x417e7b <cmp_externs+0x2b> > > > > $ /opt/llvm-toolchain/bin/llvm-objdump-12 -Dr test_cpp | grep core_extern > > [ EMPTY ] > > > > When compiled with g++ in an earlier setup this contained "core_extern". > > > > With this version of your patchser it breaks *here* when using CXX=g++ > > (and uses /usr/bin/ld as linker): > > > > g++ -g -rdynamic -Wall -O2 -DHAVE_GENHDR > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/b > > pf/tools/include -I/home/dileks/src/linux-kernel/git/include/generated > > -I/home/dileks/src/linux-kernel/git/tools/lib > > -I/home/dileks/src/linux-kernel/git/tools/include > > -I/home/dileks/src/linux-kernel/git/tools/include/uapi > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -Wno-unused-command-line-argument -Wno-format-security > > -Dbpf_prog_load=bpf_prog_test_load > > -Dbpf_load_program=bpf_test_load_program test_cpp.cpp > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a > > -lcap -lelf -lz -lrt -lpthread -o > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_cpp > > > > /usr/bin/ld: /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a(libbpf-in.o): > > relocation R_X86_64_32 against `.rodata.str1.1' ca > > n not be used when making a PIE object; recompile with -fPIE > > collect2: error: ld returned 1 exit status > > make: *** [Makefile:457: > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_cpp] > > Error 1 > > I cannot reproduce the issue with g++ with bpf-next, my command line is > > g++ -g -Og -rdynamic -Wall > -I/home/yhs/work/bpf-next/tools/testing/selftests/bpf > -I/home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/include > -I/home/yhs/work/bpf-next/include/generated > -I/home/yhs/work/bpf-next/tools/lib > -I/home/yhs/work/bpf-next/tools/include > -I/home/yhs/work/bpf-next/tools/include/uapi > -I/home/yhs/work/bpf-next/tools/testing/selftests/bpf > -Wno-unused-command-line-argument -Wno-format-security > -Dbpf_prog_load=bpf_prog_test_load > -Dbpf_load_program=bpf_test_load_program test_cpp.cpp > /home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a > -lcap -lelf -lz -lrt -lpthread -o > /home/yhs/work/bpf-next/tools/testing/selftests/bpf/test_cpp > > I modified to > g++ -g -rdynamic -Wall -O2 -DHAVE_GENHDR > -I/home/yhs/work/bpf-next/tools/testing/selftests/bpf ... > and cannot reproduce the issue. > The macro HAVE_GENHDR is only effect for test_verifier. > > > Could you try to run the above g++ command by adding > test_core_extern.skel.h back, something like > > > g++ -g -rdynamic -Wall -O2 -DHAVE_GENHDR > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/b > > pf/tools/include -I/home/dileks/src/linux-kernel/git/include/generated > > -I/home/dileks/src/linux-kernel/git/tools/lib > > -I/home/dileks/src/linux-kernel/git/tools/include > > -I/home/dileks/src/linux-kernel/git/tools/include/uapi > > -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf > > -Wno-unused-command-line-argument -Wno-format-security > > -Dbpf_prog_load=bpf_prog_test_load > > -Dbpf_load_program=bpf_test_load_program test_cpp.cpp > > test_core_extern.skel.h > > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a > > -lcap -lelf -lz -lrt -lpthread -o > > /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_cpp > > The issue could be somewhere else? > I have seen all that *skel* was reworked in bpf-next, so this is an issue here. Adding test_core_extern.skel.h: $ cd /tools/testing/selftests/bpf/ $ file test_core_extern.skel.h test_core_extern.skel.h: C source, ASCII text $ g++ -g -rdynamic -Wall -O2 -DHAVE_GENHDR -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/include -I/home/dileks/src/linux-kernel/git/include/generated -I/home/dileks/src/linux-kernel/git/tools/lib -I/home/dileks/src/linux-kernel/git/tools/include -I/home/dileks/src/linux-kernel/git/tools/include/uapi -I/home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf -Wno-unused-command-line-argument -Wno-format-security -Dbpf_prog_load=bpf_prog_test_load -Dbpf_load_program=bpf_test_load_program test_cpp.cpp test_core_extern.skel.h /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a -lcap -lelf -lz -lrt -lpthread -o /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/test_cpp /usr/bin/ld: /home/dileks/src/linux-kernel/git/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.a(libbpf-in.o): relocation R_X86_64_32 against `.rodata.str1.1' ca n not be used when making a PIE object; recompile with -fPIE collect2: error: ld returned 1 exit status Write that test_cpp.cpp in C :-)? BTW, did you check (llvm-)objdump output? $ /opt/llvm-toolchain/bin/llvm-objdump-12 -Dr test_cpp | grep core_extern - Sedat - > > > > $ grep test_cpp ../make-log_tools-testing-selftests-bpf_clang_g++.txt > > | grep test_core_extern.skel.h > > [ EMPTY ] > > > > As said I do NOT use bpf-next. > > > > - Sedat - > > > > > > > > - Sedat - > >
