update hpc stuff

lib/make-hpc-dist/default.nix

@@ -25,7 +25,7 @@ let
   base-container = runCommand "empty.sif.d" {
     buildInputs = [ coreutils ];
   } ''
-    mkdir "$out"
+    mkdir -p "$out"
     cd "$out"
     mkdir -p proc sys dev nix etc bin usr/bin .singularity.d
     ln -s /etc/sh bin/sh
@@ -44,6 +44,7 @@ let
       mkdir -p /var/lib/singularity/mnt/session
       echo "root:x:0:0:System administrator:/root:/bin/sh" > /etc/passwd
       echo > /etc/resolv.conf
+      mkdir -p "$out"
       ${singularity}/bin/singularity build "$out/empty.sif" "container/"
     '');
 
@@ -67,7 +68,7 @@ let
   base-etc = runCommand "singularity-etc" {
     buildInputs = [ coreutils bash cacert ];
   } ''
-    mkdir "$out"
+    mkdir -p "$out"
     ln -s "${shell}/bin/startup.sh" "$out/runscript"
     ln -s "${bash}/bin/bash" "$out/sh"
     ln -s "${coreutils}/bin/env" "$out/env"
@@ -110,7 +111,7 @@ let
     singularity run -B "/work:/work,/scratch:/scratch,$temp_dir/nix-store.squashfs:/nix/store:image-src=/,$temp_dir/etc:/etc" --pid --uts --ipc container-base.sif
   '';
 in runCommand "hpc-files.d" {} ''
-  mkdir "$out"
+  mkdir -p "$out"
   cp "${squashfs}" "$out/nix-store.squashfs"
   cp -r "${base-etc}" "$out/etc"
   cp "${container-image}/empty.sif" "$out/container-base.sif"