When cross compiling from host:aarch64-apple-darwin to target:x86_64-w64-mingw32 the compilation fails at stage0 with ``` ar: creating archive _build/stageBoot/linters/linters-common/build/libHSlinters-common-0.1.0.0.a ar: @/var/folders/tv/35hlch6s3y15hfvndc71l6d40000gn/T/extra-file-94844998824-68860-132: No such file or directory ``` I've narrowed down the issue with the following clues: * The file does indeed exist * My host `ar` tool doesn't support the `@` syntax and fails with `No such file or directory` because it's looking for a file that starts with `@` (instead of interpreting the `@` as special syntax) * The target `ar` tool does support `@`, but it doesn't come into play here because the error is in stage0, which uses the host `ar`. * I can successfully compile ghc using the same host and target with the `ar` that does not support `@` The conclusion thus far is that we're not taking into consideration that when host /= target the `ar` might not support the same flags CC: @bgamari