From 91572e3ff597caa8de83a54379eade5e6101ca0c Mon Sep 17 00:00:00 2001
From: Brian Han <han12@llnl.gov>
Date: Wed, 29 Jul 2026 09:34:21 -0700
Subject: [PATCH 1/4] Axom - update recipe with C++20 and +python variant
 changes

---
 .../builtin/packages/axom/package.py          | 176 ++++++++++++++----
 1 file changed, 144 insertions(+), 32 deletions(-)

diff --git a/repos/spack_repo/builtin/packages/axom/package.py b/repos/spack_repo/builtin/packages/axom/package.py
index 0f8262df5f9..18f0992b55b 100644
--- a/repos/spack_repo/builtin/packages/axom/package.py
+++ b/repos/spack_repo/builtin/packages/axom/package.py
@@ -5,6 +5,7 @@
 import os
 import shutil
 import socket
+import tempfile
 from os.path import join as pjoin
 
 from spack_repo.builtin.build_systems.cached_cmake import (
@@ -113,8 +114,11 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
     variant("tools", default=True, description="Build tools")
     variant("tutorials", default=True, description="Build tutorials")
 
-    # Hard requirement after Axom 0.6.1
-    variant("cpp14", default=True, description="Build with C++14 support")
+    variant(
+        "cpp14",
+        default=False,
+        description="Build with C++14 support. Deprecated -- use the cxxstd variant version.",
+    )
 
     variant("fortran", default=True, description="Build with Fortran support")
 
@@ -150,20 +154,24 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
     variant("adiak", default=False, when="@0.13:", description="Build with adiak")
     variant("caliper", default=False, when="@0.13:", description="Build with caliper")
     variant("conduit", default=True, description="Build with conduit")
-
-    variant("opencascade", default=False, description="Build with opencascade")
-
-    variant("mfem", default=False, description="Build with mfem")
     variant("hdf5", default=True, description="Build with hdf5")
     variant("lua", default=True, description="Build with Lua")
+    variant("mfem", default=False, description="Build with mfem")
+    variant("opencascade", default=False, description="Build with opencascade")
+    variant("raja", default=True, description="Build with raja")
     variant("scr", default=False, description="Build with SCR")
     variant("umpire", default=True, description="Build with umpire")
 
-    variant("raja", default=True, description="Build with raja")
-
     varmsg = "Build development tools (such as Sphinx, Doxygen, etc...)"
     variant("devtools", default=False, description=varmsg)
 
+    variant(
+        "cxxstd",
+        default="20",
+        values=("11", "14", "17", "20"),
+        description="C++ standard to build with",
+    )
+
     # -----------------------------------------------------------------------
     # Dependencies
     # -----------------------------------------------------------------------
@@ -278,14 +286,20 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
         depends_on("mfem~mpi", when="~mpi")
         depends_on("mfem@4.5.0:", when="@0.7.0:")
 
-    depends_on("python", when="+python")
-
     # Python
     with when("+python"):
+        depends_on("python")
+
+        # extending python allows spack environment views to import axom from python
+        extends("python")
+
         depends_on("py-nanobind@2.7.0:")
         depends_on("py-pytest")
+        depends_on("py-packaging")
+        depends_on("py-pygments")
         depends_on("py-numpy")
-        depends_on("conduit+python")
+        depends_on("py-mpi4py", when="+mpi")
+        depends_on("conduit+python", when="+conduit")
 
     # Devtools
     with when("+devtools"):
@@ -302,6 +316,7 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
         # (ENABLE_CLANGFORMAT will be OFF if not the exact version)
         depends_on("llvm+clang@19", type="build")
 
+    # -----------------------------------------------------------------------
     # Component requirements
     # -----------------------------------------------------------------------
     # Hard inter-component dependencies taken from Axom's dependency graph.
@@ -329,8 +344,13 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
     # -----------------------------------------------------------------------
     # Conflicts
     # -----------------------------------------------------------------------
-    # Hard requirement after Axom 0.6.1
-    conflicts("~cpp14", when="@0.6.2:")
+
+    # C++14 required as of 0.6.2
+    conflicts("cxxstd=11", when="@0.6.2:")
+    # C++17 required as of 0.12.0
+    conflicts("cxxstd=14", when="@0.12.0:")
+    # C++20 required as of unreleased 0.15.0
+    conflicts("cxxstd=17", when="@0.15.0:")
 
     # Conduit's cmake config files moved and < 0.4.0 can't find it
     conflicts("^conduit@0.7.2:", when="@:0.4.0")
@@ -388,6 +408,10 @@ def cache_name(self):
             special_case,
         )
 
+    @property
+    def cxx_std(self):
+        return self.spec.variants.get("cxxstd").value
+
     def initconfig_compiler_entries(self):
         spec = self.spec
         entries = super().initconfig_compiler_entries()
@@ -409,7 +433,7 @@ def initconfig_compiler_entries(self):
         else:
             entries.append(cmake_cache_option("ENABLE_FORTRAN", False))
 
-        if spec.satisfies("+cpp14") and spec.satisfies("@:0.6.1"):
+        if (spec.satisfies("+cpp14") or self.cxx_std == "14") and spec.satisfies("@:0.6.1"):
             entries.append(cmake_cache_string("BLT_CXX_STD", "c++14", ""))
 
         # Add optimization flag workaround for builds with cray compiler
@@ -449,7 +473,7 @@ def initconfig_hardware_entries(self):
 
             if spec.satisfies("^blt@:0.5.1"):
                 # This is handled internally by BLT now
-                if spec.satisfies("+cpp14"):
+                if spec.satisfies("+cpp14") or self.cxx_std == "14":
                     cudaflags += " -std=c++14"
                 else:
                     cudaflags += " -std=c++11"
@@ -499,25 +523,41 @@ def initconfig_hardware_entries(self):
                 hip_link_flags += "-lflang -lflangrti "
 
             # Additional library path for cray compiler
-            if self.spec.satisfies("%cce"):
-                lib_path = "/opt/cray/pe/cce/{0}/cce/x86_64/lib".format(self.spec.compiler.version)
+            if spec.satisfies("%cce"):
+                lib_path = "/opt/cray/pe/cce/{0}/cce/x86_64/lib".format(spec.compiler.version)
                 hip_link_flags += "-L{0} -Wl,-rpath,{0}".format(lib_path)
 
             if spec.satisfies("+fortran"):
-                link_remove_list = []
+                link_lib_remove_list = []
+                link_dir_remove_list = []
+
+                if self.cxx_std == "20":
+                    link_dir_remove_list += [
+                        "/opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12"
+                    ]
+                    link_dir_remove_list += ["/opt/rh/gcc-toolset-12/root/usr/lib64"]
 
                 # Remove extra link library for crayftn
                 if self.is_fortran_compiler("crayftn"):
-                    link_remove_list += ["unwind"]
+                    link_lib_remove_list += ["unwind"]
 
                 # Remove injected OpenMP stub library
                 if spec.satisfies("+openmp"):
-                    link_remove_list += ["ompstub"]
+                    link_lib_remove_list += ["ompstub"]
 
-                if link_remove_list:
+                if link_lib_remove_list:
                     entries.append(
                         cmake_cache_string(
-                            "BLT_CMAKE_IMPLICIT_LINK_LIBRARIES_EXCLUDE", ";".join(link_remove_list)
+                            "BLT_CMAKE_IMPLICIT_LINK_LIBRARIES_EXCLUDE",
+                            ";".join(link_lib_remove_list),
+                        )
+                    )
+
+                if link_dir_remove_list:
+                    entries.append(
+                        cmake_cache_string(
+                            "BLT_CMAKE_IMPLICIT_LINK_DIRECTORIES_EXCLUDE",
+                            ";".join(link_dir_remove_list),
                         )
                     )
 
@@ -579,7 +619,8 @@ def initconfig_hardware_entries(self):
                 cmake_cache_string("BLT_OPENMP_LINK_FLAGS", openmp_gen_exp, description)
             )
 
-        if spec.satisfies("+openmp") and spec.satisfies("+rocm") and self.spec.satisfies("%cce"):
+        # For cce up to version 20.0.0
+        if spec.satisfies("+openmp") and spec.satisfies("+rocm") and spec.satisfies("%cce@:20"):
             openmp_gen_exp = (
                 "$<$<NOT:$<COMPILE_LANGUAGE:Fortran>>:"
                 "-fopenmp=libomp>;$<$<COMPILE_LANGUAGE:"
@@ -697,9 +738,9 @@ def initconfig_package_entries(self):
         for dep in variant_deps:
             if spec.satisfies(f"^{dep}"):
                 dep_dir = get_spec_path(spec, dep, path_replacements)
-                entries.append(cmake_cache_path("%s_DIR" % dep.upper(), dep_dir))
+                entries.append(cmake_cache_path(f"{dep.upper()}_DIR", dep_dir))
             else:
-                entries.append("# %s not built\n" % dep.upper())
+                entries.append(f"# {dep.upper()} not built\n")
 
         if (spec.satisfies("+raja") or spec.satisfies("+umpire")) and spec.satisfies("^camp"):
             dep_dir = get_spec_path(spec, "camp", path_replacements)
@@ -756,6 +797,15 @@ def initconfig_package_entries(self):
             python_bin_dir = get_spec_path(spec, "python", path_replacements, use_bin=True)
             entries.append(cmake_cache_path("Python_EXECUTABLE", pjoin(python_bin_dir, "python3")))
 
+        if spec.satisfies("+python"):
+            # Install Axom's Python package(s) so a spack environment view merges them into
+            # a single site-packages and `import axom.sidre` works without updating PYTHONPATH
+            entries.append(
+                cmake_cache_path(
+                    "AXOM_PYTHON_MODULE_INSTALL_PREFIX", spec["python"].package.platlib
+                )
+            )
+
         if spec.satisfies("^py-jsonschema"):
             jsonschema_dir = get_spec_path(spec, "py-jsonschema", path_replacements, use_bin=True)
             jsonschema_path = os.path.join(jsonschema_dir, "jsonschema")
@@ -786,13 +836,23 @@ def initconfig_package_entries(self):
                 )
 
         if spec.satisfies("+python"):
+            python_platlib = spec["python"].package.platlib
+
             # pytest requires pluggy and iniconfig
-            for dep in ("py-nanobind", "py-pytest", "py-numpy", "py-pluggy", "py-iniconfig"):
+            # newer pytest releases also import packaging/pygments from separate Spack prefixes.
+            for dep in (
+                "py-nanobind",
+                "py-pytest",
+                "py-numpy",
+                "py-pluggy",
+                "py-iniconfig",
+                "py-packaging",
+                "py-pygments",
+                "py-mpi4py",
+            ):
                 if spec.satisfies("^{0}".format(dep)):
-                    dep_dir = get_spec_path(spec, dep, path_replacements, use_lib=True)
-                    py_libdir = join_path(
-                        dep_dir, f"python{spec['python'].version.up_to(2)}", "site-packages"
-                    )
+                    dep_dir = get_spec_path(spec, dep, path_replacements)
+                    py_libdir = join_path(dep_dir, python_platlib)
                     entries.append(
                         cmake_cache_path("%s_DIR" % dep.upper().replace("-", "_"), py_libdir)
                     )
@@ -837,7 +897,8 @@ def build_test(self):
     def test_install_using_cmake(self):
         """build example with cmake and run"""
         example_src_dir = join_path(self.prefix.examples.axom, "using-with-cmake")
-        example_stage_dir = "./cmake"
+        example_test_dir = tempfile.mkdtemp(prefix="axom-cmake-example-")
+        example_stage_dir = join_path(example_test_dir, "using-with-cmake")
         shutil.copytree(example_src_dir, example_stage_dir)
         with working_dir(join_path(example_stage_dir, "build"), create=True):
             cmake_args = ["-C ../host-config.cmake", example_src_dir]
@@ -853,10 +914,61 @@ def test_install_using_cmake(self):
     def test_install_using_make(self):
         """build example with make and run"""
         example_src_dir = join_path(self.prefix.examples.axom, "using-with-make")
-        example_stage_dir = "./make"
+        example_test_dir = tempfile.mkdtemp(prefix="axom-make-example-")
+        example_stage_dir = join_path(example_test_dir, "using-with-make")
         shutil.copytree(example_src_dir, example_stage_dir)
         with working_dir(example_stage_dir, create=True):
             make(f"AXOM_DIR={self.prefix}")
             example = Executable("./example")
             example()
             make("clean")
+
+    @run_after("install", when="+examples+python+tools components=sidre")
+    @on_package_attributes(run_tests=True)
+    def test_install_using_python(self):
+        """run python example against installed axom"""
+        example = join_path(self.prefix.examples.axom, "using-with-python", "example.py")
+        python_runner = join_path(self.prefix.bin, "run_python_with_axom.sh")
+        if not os.path.isfile(example):
+            raise RuntimeError("Missing installed python example: {0}".format(example))
+        if not os.path.isfile(python_runner):
+            raise RuntimeError("Missing installed python runner: {0}".format(python_runner))
+        run_python = Executable(python_runner)
+        run_python(example)
+
+    @run_after("install", when="+python components=sidre")
+    @on_package_attributes(run_tests=True)
+    def test_axom_sidre_installed_into_site_packages(self):
+        """Check axom.sidre installed into a site-packages-shaped prefix
+        and imports from view-shaped site-packages paths.
+        """
+        python_pkg = self.spec["python"].package
+        python_platlib = python_pkg.platlib
+        site_packages = join_path(self.prefix, python_platlib)
+        sidre_pkg_dir = join_path(site_packages, "axom", "sidre")
+        if not os.path.isdir(sidre_pkg_dir):
+            raise RuntimeError(
+                "axom.sidre was not installed under the interpreter platlib: {0}".format(
+                    sidre_pkg_dir
+                )
+            )
+
+        # Assemble the Python package directories a view would merge into site-packages.
+        import_path = [site_packages]
+        if self.spec.satisfies("+conduit"):
+            for conduit_py in (
+                join_path(self.spec["conduit"].prefix, python_platlib),
+                join_path(self.spec["conduit"].prefix, "python-modules"),
+            ):
+                if os.path.isdir(conduit_py):
+                    import_path.append(conduit_py)
+
+        for dep in ("py-numpy", "py-mpi4py"):
+            if self.spec.satisfies("^{0}".format(dep)):
+                dep_py = join_path(self.spec[dep].prefix, python_platlib)
+                if os.path.isdir(dep_py):
+                    import_path.append(dep_py)
+
+        imports = "import axom.sidre as s; import numpy; print('axom.sidre', s.__version__)"
+        python = Executable(join_path(self.spec["python"].prefix.bin, "python3"))
+        python("-c", imports, extra_env={"PYTHONPATH": ":".join(import_path)})

From 4124b16240eabc50f3018b83c7720a05e9e5dc74 Mon Sep 17 00:00:00 2001
From: Brian Han <han12@llnl.gov>
Date: Wed, 29 Jul 2026 13:50:20 -0700
Subject: [PATCH 2/4] Define BLT_CXX_STD in the general case

---
 repos/spack_repo/builtin/packages/axom/package.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/repos/spack_repo/builtin/packages/axom/package.py b/repos/spack_repo/builtin/packages/axom/package.py
index 18f0992b55b..b93f4bc359e 100644
--- a/repos/spack_repo/builtin/packages/axom/package.py
+++ b/repos/spack_repo/builtin/packages/axom/package.py
@@ -435,6 +435,8 @@ def initconfig_compiler_entries(self):
 
         if (spec.satisfies("+cpp14") or self.cxx_std == "14") and spec.satisfies("@:0.6.1"):
             entries.append(cmake_cache_string("BLT_CXX_STD", "c++14", ""))
+        else:
+            entries.append(cmake_cache_string("BLT_CXX_STD", f"c++{self.cxx_std}"))
 
         # Add optimization flag workaround for builds with cray compiler
         if spec.satisfies("%cce"):

From 640d900c9220980d0cbd89b1e91b5ec77e5a60be Mon Sep 17 00:00:00 2001
From: Brian Han <han12@llnl.gov>
Date: Wed, 12 Aug 2026 08:00:59 -0700
Subject: [PATCH 3/4] Cleanup python invocation

Co-authored-by: Greg Becker <becker33@llnl.gov>
---
 repos/spack_repo/builtin/packages/axom/package.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/repos/spack_repo/builtin/packages/axom/package.py b/repos/spack_repo/builtin/packages/axom/package.py
index b93f4bc359e..6ab281841e6 100644
--- a/repos/spack_repo/builtin/packages/axom/package.py
+++ b/repos/spack_repo/builtin/packages/axom/package.py
@@ -972,5 +972,5 @@ def test_axom_sidre_installed_into_site_packages(self):
                     import_path.append(dep_py)
 
         imports = "import axom.sidre as s; import numpy; print('axom.sidre', s.__version__)"
-        python = Executable(join_path(self.spec["python"].prefix.bin, "python3"))
+        python = self["python"].command
         python("-c", imports, extra_env={"PYTHONPATH": ":".join(import_path)})

From e7f39d3d90624e03f1d294c550205b4c2f30d2df Mon Sep 17 00:00:00 2001
From: Brian Han <han12@llnl.gov>
Date: Wed, 12 Aug 2026 15:53:31 -0700
Subject: [PATCH 4/4] Remove BLT_CMAKE_IMPLICIT_LINK_DIRECTORIES_EXCLUDE C++20
 logic ; mirror cxxstd variant logic

---
 .../builtin/packages/axom/package.py          | 30 +++++--------------
 1 file changed, 7 insertions(+), 23 deletions(-)

diff --git a/repos/spack_repo/builtin/packages/axom/package.py b/repos/spack_repo/builtin/packages/axom/package.py
index 6ab281841e6..5d9c8123c47 100644
--- a/repos/spack_repo/builtin/packages/axom/package.py
+++ b/repos/spack_repo/builtin/packages/axom/package.py
@@ -168,7 +168,13 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
     variant(
         "cxxstd",
         default="20",
-        values=("11", "14", "17", "20"),
+        values=(
+            conditional("11", when="@:0.6.1"),
+            conditional("14", when="@:0.11.0"),
+            conditional("17", when="@:0.14.0"),
+            "20",
+        ),
+        multi=False,
         description="C++ standard to build with",
     )
 
@@ -345,13 +351,6 @@ class Axom(CachedCMakePackage, CudaPackage, ROCmPackage):
     # Conflicts
     # -----------------------------------------------------------------------
 
-    # C++14 required as of 0.6.2
-    conflicts("cxxstd=11", when="@0.6.2:")
-    # C++17 required as of 0.12.0
-    conflicts("cxxstd=14", when="@0.12.0:")
-    # C++20 required as of unreleased 0.15.0
-    conflicts("cxxstd=17", when="@0.15.0:")
-
     # Conduit's cmake config files moved and < 0.4.0 can't find it
     conflicts("^conduit@0.7.2:", when="@:0.4.0")
 
@@ -531,13 +530,6 @@ def initconfig_hardware_entries(self):
 
             if spec.satisfies("+fortran"):
                 link_lib_remove_list = []
-                link_dir_remove_list = []
-
-                if self.cxx_std == "20":
-                    link_dir_remove_list += [
-                        "/opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12"
-                    ]
-                    link_dir_remove_list += ["/opt/rh/gcc-toolset-12/root/usr/lib64"]
 
                 # Remove extra link library for crayftn
                 if self.is_fortran_compiler("crayftn"):
@@ -555,14 +547,6 @@ def initconfig_hardware_entries(self):
                         )
                     )
 
-                if link_dir_remove_list:
-                    entries.append(
-                        cmake_cache_string(
-                            "BLT_CMAKE_IMPLICIT_LINK_DIRECTORIES_EXCLUDE",
-                            ";".join(link_dir_remove_list),
-                        )
-                    )
-
             # Additional libraries for TOSS4
             hip_link_flags += "-lamdhip64 -lhsakmt -lhsa-runtime64 -lamd_comgr "