undefined reference to '__atomic_compare_exchange_1' when running ./build_milkv.sh

[VitalyAnkh]

After running ./build_milkv.sh, I got error like this:

[riscv64-unknown-linux-musl-gcc] sample_venc.o
/home/vitalyr/projects/dev/embed/duo-buildroot-sdk/host-tools/gcc/riscv64-linux-musl-x86_64/bin/../lib/gcc/riscv64-unknown-linux-musl/10.2.0/../../../../riscv64-unknown-linux-musl/bin/ld: /home/vitalyr/projects/dev/embed/duo-buildroot-sdk/middleware/v2/lib/libsys.a(cvi_vb.o): in function `CVI_VB_Init':
/root/.jenkins/workspace/v4.1.0_release_build/middleware/v2/modules/sys/src/cvi_vb.c:201: undefined reference to `__atomic_compare_exchange_1'
/home/vitalyr/projects/dev/embed/duo-buildroot-sdk/host-tools/gcc/riscv64-linux-musl-x86_64/bin/../lib/gcc/riscv64-unknown-linux-musl/10.2.0/../../../../riscv64-unknown-linux-musl/bin/ld: /home/vitalyr/projects/dev/embed/duo-buildroot-sdk/middleware/v2/lib/libsys.a(cvi_vb.o): in function `CVI_VB_Exit':
/root/.jenkins/workspace/v4.1.0_release_build/middleware/v2/modules/sys/src/cvi_vb.c:225: undefined reference to `__atomic_compare_exchange_1'
collect2: error: ld returned 1 exit status

It seems to be already fixed by gcc toolchains([1], [2], [3]), but duo-build root-SDK will download an older gcc toolchain (gcc 10) to build the image. How about updating the toolchain?

1. Consider open-coding subword atomics or move to libgcc riscvarchive/riscv-gcc#12
2. https://www.overleaf.com/project/624c33c4e2d49b02be626e13
3. Build failure on RISC-V due missing __atomic_exchange_1 advancedtelematic/aktualizr#1427 (comment)

[xyq1113723547]

I also encountered this error.
I also notice multiple these warnings, which suggests that the toolchain is mis-configured about the ISA version.

warning: /home/yanqi/duo-buildroot-sdk/host-tools/gcc/riscv64-linux-musl-x86_64/bin/../lib/gcc/riscv64-unknown-linux-musl/10.2.0/lib64v0p7_xthead/lp64d/crtn.o: mis-matched ISA version 0.7 for 'zvlsseg' extension, the output version is 1.0

[pavelanni]

Same here. Exactly the same message as @VitalyAnkh posted.

UPDATE: I was running the build on Fedora 38 when I got the error. After that I started an Ubuntu 22.04 container with Podman, followed the instructions in the README and the build was successful.

I placed my Containerfile and the instructions here: https://github.com/pavelanni/milkv-duo-experiments/tree/main/build-container

[carbonfix]

Try using the latest code. If the compilation still fails, it is recommended that you use Docker to compile:
https://github.com/milkv-duo/duo-buildroot-sdk#2-compiled-using-docker

[xnvi]

我自己的解决方法，在sophpi/middleware/v2/sample/venc/Makefile的EXTRA_LDFLAGS 后面添加 -latomic，对vdec中的makefile同样有效