#1142560 clang-21: ROCM_PATH envvar excludes resource directory from device libs search path

Package:
1125754
Source:
1125754
Submitter:
Cordell Bloor
Date:
2026-07-21 17:37:02 UTC
Severity:
normal
#1142560#5
Date:
2026-01-16 22:50:07 UTC
From:
To:
Dear Maintainer,

clang-21 does not consider the LLVM 21 resource directory for the ROCm
device libs when ROCM_PATH is defined in the environment, unlike older
versions of LLVM (e.g., clang-17).

Various build systems will search for ROCm and then explicitly set the
ROCM_PATH during their build, which causes their builds to fail even if
the ROCM_PATH is correctly set.

To reproduce this problem consider:

    apt install -y hipcc clang-21 rocm-device-libs-21
    cat > main.hip << END
    int main() { return 0; }
    END
    clang++-21 main.hip -lamdhip64 -o main # SUCCESS
    ROCM_PATH=/usr clang++-21 main.hip -lamdhip64 -o main # FAIL

The failing output (with -v added) is:

    Debian clang version 21.1.8 (1+b1)
    Target: x86_64-pc-linux-gnu
    Thread model: posix
    InstalledDir: /usr/lib/llvm-21/bin
    Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/15
    Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/15
    Candidate multilib: .;@m64
    Selected multilib: .;@m64
    Found HIP installation: /usr, version 6.4.43484
    clang++-21: error: cannot find ROCm device library; provide its path via '--rocm-path' or '--rocm-device-lib-path', or pass '-nogpulib' to build without ROCm device library

To resolve this problem, the LLVM resource directory should always be
considered when searching for the ROCm device libraries.

Sincerely,
Cory Bloor