>> I can successfully compile and link gollvm by setting CMAKE_C_FLAGS="-fcf-protection=none".
The manual override of CMAKE_C_FLAGS shouldn't be needed, if you rerun cmake from a clean slate (removing the CMakeCache.txt, etc) it should detect that "-fcf-protection=branch" is hard-wired on, and will add the right flags under the hood to work around it. >>root@a78010e8da5d:~# go version >>go: symbol lookup error: /root/llvm-project/install-release/lib64/libgo.so.11git: undefined symbol: __go_getcontext This symbol is defined in an assembly source file in libgo. What's happening is that by setting CMAKE_C_FLAGS="-fcf-protection=none" but not also setting CMAKE_ASM_FLAGS="-fcf-protection=none" you've introduced a discrepancy between the C and Assembly compiles in libgo. If you set CMAKE_C_FLAGS, you should also set CMAKE_ASM_FLAGS. Thanks, Than On Wed, May 27, 2020 at 10:02 AM Yuan Ting <yuant...@ict.ac.cn> wrote: > Thank you for your guidance, now I can successfully compile and link > gollvm by setting CMAKE_C_FLAGS="-fcf-protection=none". But after > installing gollvm, there is still a weird problem: > > root@a78010e8da5d:~# go version > go: symbol lookup error: > /root/llvm-project/install-release/lib64/libgo.so.11git: undefined symbol: > __go_getcontext > > On Wednesday, May 27, 2020 at 12:01:06 AM UTC+8, Than McIntosh wrote: >> >> >> This looks exactly like the bug in >> https://github.com/golang/go/issues/38728. The prolog of the function >> contains >> >> 0: f3 0f 1e fa endbr64 >> >> which is confusing the gold linker. This instruction doesn't get added >> unless the host compiler has "-fcf-protection=branch" turned on. I would >> suggest deleting and recreating your build area or removing your >> CMakeCache.txt file to insure that you have a rebuild from a clean start. >> >> Thanks, Than >> >> >> On Tue, May 26, 2020 at 11:00 AM Yuan Ting <yuan...@ict.ac.cn> wrote: >> >>> OK, as follows >>> >>> ./tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o: >>> file format elf64-x86-64 >>> >>> >>> Disassembly of section .text.syscall.GetErrno: >>> >>> 0000000000000000 <syscall.GetErrno>: >>> 0: f3 0f 1e fa endbr64 >>> 4: 64 48 3b 24 25 70 00 cmp %fs:0x70,%rsp >>> b: 00 00 >>> d: 72 11 jb 20 <syscall.GetErrno+0x20> >>> f: 48 83 ec 08 sub $0x8,%rsp >>> 13: e8 00 00 00 00 callq 18 <syscall.GetErrno+0x18> >>> 14: R_X86_64_PLT32 __errno_location-0x4 >>> 18: 48 63 00 movslq (%rax),%rax >>> 1b: 48 83 c4 08 add $0x8,%rsp >>> 1f: c3 retq >>> 20: 41 ba 08 00 00 00 mov $0x8,%r10d >>> 26: 45 31 db xor %r11d,%r11d >>> 29: e8 00 00 00 00 callq 2e <syscall.GetErrno+0x2e> >>> 2a: R_X86_64_PLT32 __morestack-0x4 >>> 2e: c3 retq >>> 2f: f3 0f 1e fa endbr64 >>> 33: eb da jmp f <syscall.GetErrno+0xf> >>> >>> On Tuesday, May 26, 2020 at 10:44:03 PM UTC+8, Than McIntosh wrote: >>>> >>>> OK. Just to confirm, what do you see from >>>> >>>> objdump -dr >>>> ./tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o >>>> >>>> for the prolog of syscall.Geterrno. Should be something like >>>> >>>> Disassembly of section .text.syscall.GetErrno: >>>> >>>> 0000000000000000 <syscall.GetErrno>: >>>> 0: 64 48 3b 24 25 70 00 cmp %fs:0x70,%rsp >>>> 7: 00 00 >>>> 9: 72 11 jb 1c <syscall.GetErrno+0x1c> >>>> b: 48 83 ec 08 sub $0x8,%rsp >>>> f: e8 00 00 00 00 callq 14 <syscall.GetErrno+0x14> >>>> 10: R_X86_64_PLT32 __errno_location-0x4 >>>> >>>> Thanks, Than >>>> >>>> ? >>>> >>>> On Tue, May 26, 2020 at 10:05 AM Yuan Ting <yuan...@ict.ac.cn> wrote: >>>> >>>>> Fine, that is >>>>> >>>>> [1/3] /usr/bin/cc -D_DEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS >>>>> -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools/gollvm/libgo >>>>> -I/root/llvm-project/llvm/tools/gollvm/libgo -Iinclude >>>>> -I/root/llvm-project/llvm/include >>>>> -I/root/llvm-project/llvm/tools/gollvm/gofrontend/libgo/runtime >>>>> -Itools/gollvm/libgo/runtime >>>>> -I/root/llvm-project/llvm/tools/gollvm/libgo/libbacktrace -fPIC >>>>> -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings >>>>> -Wno-missing-field-initializers -pedantic -Wno-long-long >>>>> -Wimplicit-fallthrough -Wno-comment -fdiagnostics-color >>>>> -ffunction-sections >>>>> -fdata-sections -O3 -fPIC -g -Wno-zero-length-array -fsplit-stack >>>>> -D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -UNDEBUG -MD >>>>> -MT >>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o >>>>> -MF >>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o.d >>>>> -o >>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o >>>>> -c >>>>> /root/llvm-project/llvm/tools/gollvm/gofrontend/libgo/go/syscall/errno.c >>>>> >>>>> On Tuesday, May 26, 2020 at 8:41:18 PM UTC+8, Than McIntosh wrote: >>>>>> >>>>>> OK. >>>>>> >>>>>> I'm wondering if for some reason the fix I put in is not effective. >>>>>> >>>>>> Could you please try this in your build area: >>>>>> >>>>>> rm >>>>>> ./tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o >>>>>> ninja -v libgo_all >>>>>> >>>>>> and post the compile line for errno.c? >>>>>> >>>>>> Thanks, Than >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Tue, May 26, 2020 at 7:21 AM Yuan Ting <yuan...@ict.ac.cn> wrote: >>>>>> >>>>>>> Yes, I'm sure I fetched the last version of gollvm, >>>>>>> i.e. 0edc44a02852dd0d56cac35163a45634b497d6cd >>>>>>> >>>>>>> On Tuesday, May 26, 2020 at 6:55:08 PM UTC+8, Than McIntosh wrote: >>>>>>>> >>>>>>>> Hello, >>>>>>>> >>>>>>>> The ld.gold error message looks a lot like one reported in a >>>>>>>> previous bug, https://github.com/golang/go/issues/38728. >>>>>>>> >>>>>>>> Can you please check to make sure that your client is sync'd past >>>>>>>> the CLs that fix this issue, e.g. >>>>>>>> 0edc44a02852dd0d56cac35163a45634b497d6cd. >>>>>>>> >>>>>>>> Thanks, Than >>>>>>>> >>>>>>>> >>>>>>>> On Mon, May 25, 2020 at 10:15 PM Yuan Ting <yuan...@ict.ac.cn> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> I tried to build gollvm in a docker container (the image is based >>>>>>>>> on ubuntu 20.04, and the host OS is MacOS catalina). I configured >>>>>>>>> llvm by >>>>>>>>> >>>>>>>>> SHELL=/bin/sh cmake -DCMAKE_BUILD_TYPE=Release >>>>>>>>> -DLLVM_TARGETS_TO_BUILD=X86 -DLLVM_ENABLE_ASSERTIONS=On >>>>>>>>> -DLLVM_ENABLE_RTTI=On -DLLVM_USE_LINKER=gold -G Ninja ../llvm >>>>>>>>> >>>>>>>>> and then build and install gollvm by >>>>>>>>> >>>>>>>>> ninja gollvm && ninja install-gollvm >>>>>>>>> >>>>>>>>> after a while, I encountered >>>>>>>>> >>>>>>>>> ... >>>>>>>>> >>>>>>>>> error: At most two relocations per offset are supported >>>>>>>>> >>>>>>>>> error: At most two relocations per offset are supported >>>>>>>>> >>>>>>>>> error: At most two relocations per offset are supported >>>>>>>>> >>>>>>>>> [212/1279] Creating >>>>>>>>> /root/llvm-project/build-debug/tools/gollvm/libgo/tmp-sigtab.go >>>>>>>>> >>>>>>>>> FAILED: tools/gollvm/libgo/tmp-sigtab.go >>>>>>>>> >>>>>>>>> cd /root/llvm-project/build-debug/tools/gollvm/libgo && >>>>>>>>> GOARCH=amd64 GOOS=linux /bin/sh >>>>>>>>> /root/llvm-project/llvm/tools/gollvm/libgo/capturescript.sh >>>>>>>>> /root/llvm-project/llvm/tools/gollvm/gofrontend/libgo/mksigtab.sh >>>>>>>>> /root/llvm-project/build-debug/tools/gollvm/libgo/tmp-sigtab.go >>>>>>>>> >>>>>>>>> error: no SHELL setting >>>>>>>>> >>>>>>>>> [214/1279] Creating >>>>>>>>> /root/llvm-project/build-debug/tools/gollvm/libgo/tmp-sysinfo.go >>>>>>>>> >>>>>>>>> ninja: build stopped: subcommand failed. >>>>>>>>> >>>>>>>>> >>>>>>>>> By add SHELL=/bin/sh, the errors above seems to be skipped but >>>>>>>>> another period of time: >>>>>>>>> >>>>>>>>> >>>>>>>>> ... >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o: >>>>>>>>> failed to match split-stack sequence at section 4 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/errno.c.o: >>>>>>>>> failed to match split-stack sequence at section 6 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libgo_c_piclib.dir/__/gofrontend/libgo/go/syscall/signame.c.o: >>>>>>>>> failed to match split-stack sequence at section 5 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libbacktrace_piclib.dir/libbacktrace/backtrace.c.o: >>>>>>>>> failed to match split-stack sequence at section 4 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libbacktrace_piclib.dir/libbacktrace/backtrace.c.o: >>>>>>>>> failed to match split-stack sequence at section 6 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libbacktrace_piclib.dir/libbacktrace/dwarf.c.o: >>>>>>>>> failed to match split-stack sequence at section 18 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libbacktrace_piclib.dir/libbacktrace/dwarf.c.o: >>>>>>>>> failed to match split-stack sequence at section 79 offset 0 >>>>>>>>> >>>>>>>>> ... >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libffi_piclib.dir/libffi/src/x86/ffi64.c.o: >>>>>>>>> failed to match split-stack sequence at section 22 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libffi_piclib.dir/libffi/src/x86/ffi64.c.o: >>>>>>>>> failed to match split-stack sequence at section 26 offset 0 >>>>>>>>> >>>>>>>>> /usr/bin/ld.gold: error: >>>>>>>>> tools/gollvm/libgo/CMakeFiles/libffi_piclib.dir/libffi/src/x86/ffiw64.c.o: >>>>>>>>> failed to match split-stack sequence at section 16 offset 0 >>>>>>>>> >>>>>>>>> collect2: error: ld returned 1 exit status >>>>>>>>> >>>>>>>>> [901/1066] Linking C static library tools/gollvm/libgo/libgo.a >>>>>>>>> >>>>>>>>> ninja: build stopped: subcommand failed. >>>>>>>>> >>>>>>>>> >>>>>>>>> I'm not sure the error is caused by the container environment or >>>>>>>>> my configurations/other prerequisites. >>>>>>>>> >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "golang-nuts" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to golan...@googlegroups.com. >>>>>>>>> To view this discussion on the web visit >>>>>>>>> https://groups.google.com/d/msgid/golang-nuts/23309451-cb0a-4f7b-93a1-27038187302a%40googlegroups.com >>>>>>>>> <https://groups.google.com/d/msgid/golang-nuts/23309451-cb0a-4f7b-93a1-27038187302a%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>> . >>>>>>>>> >>>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "golang-nuts" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to golan...@googlegroups.com. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/golang-nuts/1ffd3fb4-e739-4f13-9168-565e4c64bc70%40googlegroups.com >>>>>>> <https://groups.google.com/d/msgid/golang-nuts/1ffd3fb4-e739-4f13-9168-565e4c64bc70%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>> . >>>>>>> >>>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "golang-nuts" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to golan...@googlegroups.com. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/golang-nuts/2e9d2af9-7d78-443b-9cda-34d7b9c41623%40googlegroups.com >>>>> <https://groups.google.com/d/msgid/golang-nuts/2e9d2af9-7d78-443b-9cda-34d7b9c41623%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "golang-nuts" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to golan...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/golang-nuts/975b8157-5795-4c09-9aed-91278aa5f0e6%40googlegroups.com >>> <https://groups.google.com/d/msgid/golang-nuts/975b8157-5795-4c09-9aed-91278aa5f0e6%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/51910be4-ce4a-49a0-91f4-1e1cc63902f6%40googlegroups.com > <https://groups.google.com/d/msgid/golang-nuts/51910be4-ce4a-49a0-91f4-1e1cc63902f6%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. 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