Hi, The package clang-runtime@3.6.2 is broken (commit 6bed29b) and giving a look to:
<https://data.guix.gnu.org/repository/1/branch/master/package/clang-runtime/output-history> it seems broken since long time. I propose to remove: clang clang-runtime clang-toolchain @3.6.2. Any objection? Note that llvm@3.6.2 cannot be removed because of the package clamav. Cheers, simon