Updates from GMAO macOS Testing

repos/spack_repo/builtin/packages/fms/llvmflang.patch

@@ -0,0 +1,26 @@
+--- a/cmake/fms_compiler_flags.cmake
++++ b/cmake/fms_compiler_flags.cmake
+@@ -7,6 +7,8 @@ if(CMAKE_Fortran_COMPILER_ID MATCHES "GNU")
+ elseif(CMAKE_Fortran_COMPILER_ID STREQUAL "Intel")
+   include(compiler_flags_Intel_Fortran)
+ elseif(CMAKE_Fortran_COMPILER_ID STREQUAL "IntelLLVM")
+   include(compiler_flags_IntelLLVM_Fortran)
++elseif(CMAKE_Fortran_COMPILER_ID STREQUAL "LLVMFlang")
++  include(compiler_flags_LLVMFlang_Fortran)
+ else()
+   message(WARNING "Fortran compiler with ID ${CMAKE_Fortran_COMPILER_ID} will be used with CMake default options")
+ endif()
+--- /dev/null
++++ b/cmake/compiler_flags_LLVMFlang_Fortran.cmake
+@@ -0,0 +1,11 @@
++# Precision-based Fortran compiler flags
++set(r8_flags "-fdefault-real-8 -fdefault-double-8")
++set(r4_flags "-fdefault-real-4")
++
++# LLVM Flang
++set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
++set(CMAKE_Fortran_FLAGS_RELEASE "-O2")
++set(CMAKE_Fortran_FLAGS_DEBUG "-O0 -g")
++set(CMAKE_Fortran_LINK_FLAGS "")
++
++# UFS flags are not known for LLVM Flang.

repos/spack_repo/builtin/packages/fms/package.py

@@ -101,6 +101,10 @@ class Fms(CMakePackage):
         when="@2023.03",
     )
 
+    # Add LLVM Flang precision flags. Based on the GEOS Baselibs patch:
+    # https://github.com/GEOS-ESM/ESMA-Baselibs/blob/main/patches/FMS/llvm.patch
+    patch("llvmflang.patch", when="@2026.01.01 %fortran=clang")
+
     variant(
         "portable_kinds",
         description="Use iso_c_binding variable kinds",

repos/spack_repo/builtin/packages/hdf5/package.py

@@ -554,6 +554,22 @@ def is_enabled(text):
     def setup_build_environment(self, env: EnvironmentModifications) -> None:
         env.set("SZIP_INSTALL", self.spec["szip"].prefix)
 
+    @run_before("cmake")
+    def fix_darwin_fortran_link_flags(self):
+        if not self.spec.satisfies("@2.0.0: platform=darwin") or not (
+            self.spec.satisfies("%fortran=clang") or self.spec.satisfies("%fortran=nag")
+        ):
+            return
+
+        # HDF5 uses CMake's C linker flag variables for version flags on all
+        # targets. Forward them explicitly so Flang and NAG pass them to ld.
+        filter_file(
+            'LINK_FLAGS "${CMAKE_C_OSX_CURRENT_VERSION_FLAG}${PACKAGE_CURRENT} ${CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG}${PACKAGE_COMPATIBILITY}"',
+            'LINK_FLAGS "-Wl,-current_version -Wl,${PACKAGE_CURRENT} -Wl,-compatibility_version -Wl,${PACKAGE_COMPATIBILITY}"',
+            "config/HDF5Macros.cmake",
+            string=True,
+        )
+
     def cmake_args(self):
         spec = self.spec
 
@@ -646,6 +662,31 @@ def cmake_args(self):
             # NAG cannot pass Spack's padded build rpath through its linker.
             args.append(self.define("CMAKE_SKIP_RPATH", True))
 
+        if spec.satisfies("@2.0.0: platform=darwin %fortran=clang"):
+            # CMake's generic Darwin rule sends -install_name directly to the
+            # driver, but LLVM Flang requires Darwin linker flags via
+            # -Xlinker. CMake emits this flag and its value separately.
+            args.append(
+                self.define(
+                    "CMAKE_SHARED_LIBRARY_SONAME_Fortran_FLAG",
+                    "-Xlinker -install_name -Xlinker ",
+                )
+            )
+
+        if spec.satisfies("@2.0.0: platform=darwin +mpi +fortran") and (
+            spec.satisfies("%fortran=clang") or spec.satisfies("%fortran=nag")
+        ):
+            # HDF5's nested Fortran project loses the OpenMPI module directory
+            # discovered by FindMPI, so its generated modules cannot resolve
+            # mpi_f08.mod (Flang) or mpi.mod (NAG) while building the high-level
+            # Fortran library.
+            args.append(
+                self.define(
+                    "MPI_Fortran_INCLUDE_DIRS",
+                    f"{spec['mpi'].prefix.include};{spec['mpi'].prefix.lib}",
+                )
+            )
+
         return args
 
     @run_after("install")

repos/spack_repo/builtin/packages/llvm/package.py

@@ -55,14 +55,21 @@ class Llvm(CMakePackage, CudaPackage, LlvmDetection, CompilerPackage):
     # Note: remember to update `provides("libllvm")` according to major versions listed
 
     # Latest stable
+    version("23.1.2", sha256="75788d759e6987a910975b902f554dc77c08b076b945b2cebde54116d8e831ca")
+    version("23.1.1", sha256="851b3d701a4fbdd9f69536d4acda578469e810ca7056687d6556443f5fd39557")
+    version("23.1.0", sha256="d8657b2a7291e518407bf13c4b41c85ef2cded2d4354097a2f451644dfc817b0")
+
+    # Previous stable series releases
+    version("22.1.8", sha256="ad18b70e287954c3d62bc7e0b86e7b7af2adf87bcfce21c15fe717f101d7aace")
+    version("22.1.7", sha256="da1578ea1faf2050e4b1923fce150b5656db1dbdeda71fe02498ac04f35b03d3")
+    version("22.1.6", sha256="ba534c6835a5b9c2162c806e269799fe41fca952a3c25baff1afcff23841ec2b")
     version("22.1.5", sha256="263e99bd0b590664a886b0332037ff060e108f4e7b0310b7c8277208858f867d")
     version("22.1.4", sha256="e813bf8da34ec2b7c108c4067937380fa7d5a04a13f4fe13555dbe388482d69f")
     version("22.1.3", sha256="7e144bd6da8177757434cc0dfd1476122f143413df379c6d6cf03843512b5a9e")
     version("22.1.2", sha256="a252efd7a4a268d2cc5145b17adcaa82757fdee1d06d748b4c24137807710ecb")
     version("22.1.1", sha256="c48878550911a8a8993a749e6118446082656768e62b26456ac7d39c4422b409")
     version("22.1.0", sha256="933765a1c2cd518d95a9033a92d88d7109a79aefa4609247c31f28b8bc8dd96e")
 
-    # Previous stable series releases
     version("21.1.8", sha256="7ba3f2a8d8fda88be18a31d011e8195d3b7f87f9fa92b20c94cba2d7f65b0e3f")
     version("21.1.7", sha256="9ee167cdf8f6b5221d6b02dbe9a664cf8c6fee70fab071aaa4a3889c7c265258")
     version("21.1.6", sha256="2380973eb435b48bd70881939da3629069009a851c81676dfb211a1b068d72a6")
@@ -272,6 +279,7 @@ class Llvm(CMakePackage, CudaPackage, LlvmDetection, CompilerPackage):
 
     variant("utils", default=False, description="Install utility binaries (FileCheck, etc.)")
 
+    provides("libllvm@23", when="@23")
     provides("libllvm@22", when="@22")
     provides("libllvm@21", when="@21")
     provides("libllvm@20", when="@20")

repos/spack_repo/builtin/packages/openmpi/package.py

@@ -999,10 +999,24 @@ def libs(self):
         return find_libraries(libraries, root=self.prefix, shared=True, recursive=True)
 
     def setup_build_environment(self, env: EnvironmentModifications) -> None:
-        # We need to unset MACOSX_DEPLOYMENT_TARGET on macOS if building with NAG Fortran
-        if self.spec.satisfies("platform=darwin") and self.spec.satisfies("%fortran=nag"):
+        # Match OpenMPI's Darwin configuration when using Flang or NAG.
+        # It avoids a shared-library path that these compilers do not support
+        # for the older Fortran bindings.
+        if self.spec.satisfies("platform=darwin") and (
+            self.spec.satisfies("%fortran=nag") or self.spec.satisfies("%fortran=clang")
+        ):
             env.unset("MACOSX_DEPLOYMENT_TARGET")
 
+    @run_after("configure")
+    def fix_darwin_flang_libtool(self):
+        if not self.spec.satisfies("platform=darwin %fortran=clang"):
+            return
+
+        # Libtool recognizes a direct `flang` command but not Spack's absolute
+        # compiler-wrapper path.  Consequently it passes Darwin linker flags
+        # directly to Flang instead of through -Wl,.
+        filter_file(r"flang\*", r"*/flang|flang*", "libtool")
+
     def setup_run_environment(self, env: EnvironmentModifications) -> None:
         # Because MPI is both a runtime and a compiler, we have to setup the
         # compiler components as part of the run environment.

repos/spack_repo/builtin/packages/parallelio/package.py

@@ -108,6 +108,15 @@ def cmake_args(self):
         if spec.satisfies("%nag"):
             # NAG cannot pass Spack's padded build rpath through its linker.
             args.append(define("CMAKE_SKIP_RPATH", True))
+        if spec.satisfies("platform=darwin %fortran=clang"):
+            # CMake's generic Darwin rule sends -install_name directly to the
+            # compiler driver, but LLVM Flang requires linker flags via -Xlinker.
+            args.append(
+                define(
+                    "CMAKE_SHARED_LIBRARY_SONAME_Fortran_FLAG",
+                    "-Xlinker -install_name -Xlinker ",
+                )
+            )
         if spec.satisfies("+ncint"):
             args.extend([define("PIO_ENABLE_NETCDF_INTEGRATION", True)])
         if spec.satisfies("+pnetcdf"):

repos/spack_repo/builtin/packages/pfunit/package.py

@@ -137,6 +137,18 @@ def patch(self):
         for file in glob.glob("*/CMakeLists.txt"):
             filter_file(r".*/mod($|[^\w].*)", "", file)
 
+    @run_before("cmake")
+    def fix_darwin_llvmflang_ranlib(self):
+        if self.spec.satisfies("platform=darwin %fortran=clang"):
+            # pFUnit's macOS override passes a GNU ranlib-only option that
+            # LLVM ranlib rejects. CMake's default archive rule is valid.
+            filter_file(
+                "if (APPLE)",
+                'if (APPLE AND NOT CMAKE_Fortran_COMPILER_ID STREQUAL "LLVMFlang")',
+                "CMakeLists.txt",
+                string=True,
+            )
+
     def url_for_version(self, version):
         url_base = "https://github.com/Goddard-Fortran-Ecosystem/pFUnit"
         # Version 4.2.3+ has a v...