Set a compiler's MODULEPATH before its meta-module loads modules

configs/sites/tier1/hercules/packages_oneapi-2025.3.1.yaml

@@ -26,6 +26,8 @@ packages:
         environment:
           prepend_path:
             LD_LIBRARY_PATH: '/usr/lib:/usr/lib64'
+            # EPIC-installed oneAPI compiler module
+            MODULEPATH: '/apps/contrib/spack-stack/modulefiles'
   intel-oneapi-mkl:
     buildable: false
     externals:

configs/sites/tier1/orion/packages_oneapi-2025.3.1.yaml

@@ -26,6 +26,8 @@ packages:
         environment:
           prepend_path:
             LD_LIBRARY_PATH: '/usr/lib:/usr/lib64'
+            # EPIC-installed oneAPI compiler module
+            MODULEPATH: '/apps/contrib/spack-stack/modulefiles'
   intel-oneapi-mkl:
     buildable: false
     externals:

spack-ext/lib/spack-stack/stack/meta_modules.py

@@ -424,20 +424,25 @@ def setup_meta_modules():
     compiler_subs["COMPFLAGS"] = compiler_subs["COMPFLAGS"].rstrip("\n")
     logging.debug("  ... ... COMPFLAGS: {}".format(compiler_subs["COMPFLAGS"]))
 
-    # Environment variables
+    # MODULEPATH must be set before the module loads, https://github.com/JCSDA/spack-stack/issues/2144
+    compiler_modulepaths = ""
     if "environment" in compiler.extra_attributes.keys():
         for action in compiler.extra_attributes["environment"].keys():
             for env_name in compiler.extra_attributes["environment"][action]:
                 if action == "unset":
                     env_values = None
                 else:
                     env_values = compiler.extra_attributes["environment"][action][env_name]
-                compiler_subs["ENVVARS"] += envmod_command(
+                command = envmod_command(
                     module_choice,
                     action,
                     env_name,
                     env_values
                 )
+                if env_name == "MODULEPATH":
+                    compiler_modulepaths += command
+                else:
+                    compiler_subs["ENVVARS"] += command
     # https://github.com/JCSDA/spack-stack/issues/1903
     # Attempt to locate directory "compiler" in the same directory where
     # "icx" resides. If found, add it to PATH in the compiler module
@@ -455,6 +460,7 @@ def setup_meta_modules():
     # Spack compiler module hierarchy - append all saved modulepaths
     for modulepath in MODULEPATHS_SAVE:
         compiler_subs["MODULEPATHS"] += modulepath_prepend_command(module_choice, modulepath)
+    compiler_subs["MODULEPATHS"] += compiler_modulepaths
     compiler_subs["MODULEPATHS"] = compiler_subs["MODULEPATHS"].rstrip("\n")
     logging.debug("  ... ... MODULEPATHS  : {}".format(compiler_subs["MODULEPATHS"]))
 

spack-ext/lib/spack-stack/tests/test_setup_meta_modules.py

@@ -59,6 +59,8 @@ def test_setup_meta_modules():
         environment:
           unset:
           - DUMMYVAR
+          prepend_path:
+            MODULEPATH: /opt/test-compiler-modulefiles
   mpi:
     buildable: false
   openmpi:
@@ -89,6 +91,15 @@ def test_setup_meta_modules():
         f"Expected module {expected_comp_meta_module} not found"
     )
 
+    # The compiler's MODULEPATH must be set before the module loads that need it
+    with open(expected_comp_meta_module) as f:
+        comp_meta_module = f.read()
+    modulepath_line = "prepend-path {MODULEPATH} {/opt/test-compiler-modulefiles}"
+    load_line = "module load gcc/11.5.0"
+    assert modulepath_line in comp_meta_module
+    assert load_line in comp_meta_module
+    assert comp_meta_module.index(modulepath_line) < comp_meta_module.index(load_line)
+
     expected_mpi_meta_module = os.path.join(module_dir, "gcc", "11.5.0", "stack-openmpi", "5.0.8")
     assert(
         os.path.exists(expected_mpi_meta_module),