Fix chicken and egg problem where EESSI_ACCELERATOR_TARGET is not set by the EESSI module, unless the installation directory already exists.

Author: Caspar van Leeuwen

EESSI-install-software.sh

@@ -150,6 +150,24 @@ else
       # make sure the the software and modules directory exist
       # (since it's expected by init/eessi_environment_variables when using archdetect and by the EESSI module)
       mkdir -p ${EESSI_PREFIX}/software/${EESSI_OS_TYPE}/${EESSI_SOFTWARE_SUBDIR_OVERRIDE}/{modules,software}
+
+      # If EESSI_ACCELERATOR_TARGET_OVERRIDE is defined, we are building for an accelerator target
+      # In that case, make sure the modulepath for the accelerator subdir exists, otherwise the EESSI module will not
+      # set EESSI_ACCELERATOR_TARGET and the if-condition later in this script which checks if EESSI_ACCELERATOR_TARGET
+      # is equal to EESSI_ACCELERATOR_TARGET_OVERRIDE will fail 
+      # See https://github.com/EESSI/software-layer-scripts/pull/59#issuecomment-3173593882
+      if [ -z $EESSI_ACCEL_SOFTWARE_SUBDIR_OVERRIDE ]; then
+          mkdir -p ${EESSI_PREFIX}/software/${EESSI_OS_TYPE}/${EESSI_SOFTWARE_SUBDIR_OVERRIDE}/${EESSI_ACCELERATOR_TARGET_OVERRIDE}/modules/all
+      else
+          # At runtime, one might want to use a different CPU subdir for a given accelerator. E.g. one could use
+          # a zen2 CPU subdir on a zen4 node if the required GPU software isn't available in the zen4 tree.
+          # At build time, this doesn't make a lot of sense: we'd probably build in a CPU prefix that is different
+          # from what the code will be optimized for, and we wouldn't want that
+          msg="When building the software subdirectory for the CPU should almost certainly be that of the host."
+          msg="$msg If you think this is incorrect, please implement behaviour that makes sense in "
+          msg="$msg EESSI-software-installation.sh, essentially replacing this error."
+          fatal_error "$msg"
+      fi
   )
 fi