Function ld_library_path_value 

pub fn ld_library_path_value(
    vendor: Option<GpuVendor>,
    libtorch_lib: &str,
    rocm_lib: &str,
) -> String

LD_LIBRARY_PATH VALUE for running against libtorch_lib, in the order the loader must see it. The sibling of ld_library_path_lines, which prints the same ordering as a shell recipe; this one is for setting on a child process.

rocm_lib is the system runtime’s LIBRARY directory, passed rather than resolved here because the two callers describe different filesystems: a locally spawned child gets this box’s resolved directory (local_rocm_lib_dir), while a path composed for a REMOTE host must use the convention (/opt/rocm/lib) since our own environment says nothing about theirs.

On ROCm the system runtime must come FIRST. libtorch-rocm bundles the entire userspace ROCm stack, so with libtorch first that bundle wins over the host’s, and when it disagrees with the host’s amdkfd driver the process segfaults at its FIRST GPU OP — a failure that looks nothing like a library-path problem. A path that does not exist is skipped by the loader, so prefixing costs nothing on a box without ROCm.