Attach NEWLAPACK link options to targets

Inject the new targets into the Reference LAPACK build process.
Don't overwrite CMAKE_OSX_SYSROOT in CMake cache.
Improve status reporting.

CMakeLists.txt

@@ -37,6 +37,10 @@ if (NOT IS_TOP_LEVEL)
     message(FATAL_ERROR "This project is meant to be built as a stand-alone project, only.")
 endif ()
 
+option(BUILD_INDEX64 "Link to ILP64 version of LAPACK?" OFF)
+
+message(STATUS "Trying to link to ILP64 interface of LAPACK: ${BUILD_NEW_LAPACK}")
+
 if (CMAKE_HOST_SYSTEM_NAME MATCHES "Darwin")
     # The available binary Accelerate version is determined by the MacOS system
     message(STATUS "The Darwin kernel version is: ${CMAKE_HOST_SYSTEM_VERSION}")
@@ -53,14 +57,21 @@ if (CMAKE_HOST_SYSTEM_NAME MATCHES "Darwin")
         set(VALID_MACOS_SDK_VERSIONS 14.5 14.4 14.2 14.0 13.3)
         set(ACCELERATE_NEW_LAPACK_VERSION 3.9.1)
     else ()
+        # Before Mac OS X 13.3 Ventura
         message(FATAL_ERROR "You need at least MacOS 13.3 Ventura for Accelerate with BLAS/LAPACK v3.9.1!")
     endif ()
 
-    message(STATUS "The BLAS/LAPACK version provided by the Accelerate framework is: ${ACCELERATE_NEW_LAPACK_VERSION}")
+    message(STATUS "The BLAS/LAPACK version provided by the Accelerate framework should be: ${ACCELERATE_NEW_LAPACK_VERSION}")
+else ()
+    message(FATAL_ERROR "Accelerate is only available on MacOS!")
+endif ()
+
+if (NOT DEFINED CMAKE_OSX_SYSROOT OR CMAKE_OSX_SYSROOT STREQUAL "")
+    message(FATAL_ERROR "Please provide the CMAKE_OSX_SYSROOT location! See <https://cmake.org/cmake/help/latest/variable/CMAKE_OSX_SYSROOT.html>")
 endif ()
 
 string(REGEX MATCH [=[SDKs/MacOSX(.*)\.sdk$]=] _REGEX_DUMMY "${CMAKE_OSX_SYSROOT}")
-set(DEFAULT_MACOS_SDK_VERSION "${CMAKE_MATCH_1}")
+set(MAIN_MACOS_SDK_VERSION "${CMAKE_MATCH_1}")
 
 # The text-based .dylib stubs describing the Accelerate framework are provided
 # by the MacOS SDK, which has to match the MacOS system. Otherwise, there might
@@ -69,16 +80,17 @@ set(DEFAULT_MACOS_SDK_VERSION "${CMAKE_MATCH_1}")
 if (NOT DEFINED VALID_MACOS_SDK_VERSIONS)
     # MacOS system supports the latest iteration of the new Accelerate
     # BLAS/LAPACK. Use the default SDK, if it's recent enough.
-    if (DEFAULT_MACOS_SDK_VERSION VERSION_LESS MINIMUM_MACOS_SDK_VERSION)
+    if (MAIN_MACOS_SDK_VERSION VERSION_LESS MINIMUM_MACOS_SDK_VERSION)
         message(STATUS "The MacOS SDK is: ${CMAKE_OSX_SYSROOT}")
         message(STATUS "The minimum compatible MacOS SDK version is: ${MINIMUM_MACOS_SDK_VERSION}")
         message(FATAL_ERROR "Please install a more recent XCode for a compatible MacOS SDK.")
     endif ()
-elseif (NOT DEFAULT_MACOS_SDK_VERSION IN_LIST VALID_MACOS_SDK_VERSIONS)
+elseif (NOT MAIN_MACOS_SDK_VERSION IN_LIST VALID_MACOS_SDK_VERSIONS)
     # MacOS system supports one of the past iterations of the new Accelerate
-    # BLAS/LAPACK. If the latest possible XCode is installed is installed on
-    # this older system, there might be a mismatch between the SDK and the
-    # system binary. Find a matching SDK from the Command Line Tools instead. 
+    # BLAS/LAPACK. If the latest possible XCode is installed on this older
+    # system, there might be a mismatch between the SDK and the system binary.
+    # Find a matching SDK from the Command Line Tools instead (which must be
+    # manually installed).
     foreach (_MACOS_SDK_VERSION IN LISTS VALID_MACOS_SDK_VERSIONS)
         find_path(VALID_MACOS_SDK NAMES "MacOSX${_MACOS_SDK_VERSION}.sdk" HINTS "/Library/Developer/CommandLineTools/SDKs" NO_CACHE)
 
@@ -89,7 +101,8 @@ elseif (NOT DEFAULT_MACOS_SDK_VERSION IN_LIST VALID_MACOS_SDK_VERSIONS)
     endforeach ()
 
     if (VALID_MACOS_SDK)
-        set(CMAKE_OSX_SYSROOT "${VALID_MACOS_SDK}" CACHE PATH "" FORCE)
+        # Override CMAKE_OSX_SYSROOT with a local variable.
+        set(CMAKE_OSX_SYSROOT "${VALID_MACOS_SDK}")
     else ()
         message(STATUS "The MacOS SDK is: ${CMAKE_OSX_SYSROOT}")
         message(STATUS "The compatible MacOS SDK versions are: ${VALID_MACOS_SDK_VERSIONS}")
@@ -104,8 +117,10 @@ set(ENV{CMAKE_FRAMEWORK_PATH} "${CMAKE_OSX_SYSROOT}/System/Library/Frameworks")
 set(BLA_VENDOR "Apple")
 find_package(LAPACK MODULE)
 
+unset(ENV{CMAKE_FRAMEWORK_PATH})
+
 if (NOT LAPACK_FOUND OR NOT LAPACK_Accelerate_LIBRARY)
-    message(FATAL_ERROR "Couldn't find Accelerate framework!")
+    message(FATAL_ERROR "Couldn't find Accelerate framework in MacOS SDK!")
 endif ()
 
 add_subdirectory(src)

CMakePresets.json

@@ -13,16 +13,6 @@
         "CMAKE_INSTALL_PREFIX": "$env{HOME}/.local"
       }
     },
-    {
-      "name": "cmake4",
-      "hidden": true,
-      "cacheVariables": {
-        "CMAKE_OSX_SYSROOT": "macosx"
-      },
-      "environment": {
-        "CMAKE_POLICY_VERSION_MINIMUM": "3.5"
-      }
-    },
     {
       "name": "make",
       "hidden": true,

README.md

@@ -27,7 +27,8 @@ SOFTWARE.
 
 Since MacOS 13.3 Ventura, Apple's Accelerate framework comes with a new
 [BLAS/LAPACK interface][accelerate-docs] compatible with [Reference LAPACK
-v3.9.1][lapack-v3.9.1]. It also provides an ILP64 interface. On Apple Silicon
+v3.9.1][lapack-v3.9.1] in addition to the quite outdated [Reference LAPACK
+v3.2.1][lapack-v3.2.1]. It also provides an ILP64 interface. On Apple Silicon
 M-processors, it utilises the [proprietary AMX co-processor][apple-amx], which
 makes it especially interesting. Unfortunately, it comes without the LAPACKE
 C-interface library.
@@ -44,6 +45,7 @@ include the Accelerate C/C++ headers.
 
 [accelerate-docs]: https://developer.apple.com/documentation/accelerate/blas-library
 [apple-amx]: https://github.com/corsix/amx
+[lapack-v3.2.1]: https://netlib.org/lapack/#_lapack_version_3_2_1
 [lapack-v3.9.1]: https://github.com/Reference-LAPACK/lapack/releases/tag/v3.9.1
 [lapack-v3.11.0]: https://github.com/Reference-LAPACK/lapack/releases/tag/v3.11.0
 [macos15-release-notes]: https://developer.apple.com/documentation/macos-release-notes/macos-15-release-notes
@@ -102,9 +104,10 @@ parses the symbols listed in the BLAS and LAPACK text-based `.dylib` stubs. For
 every symbol that ends in `$NEWLAPACK` (or `$NEWLAPACK$ILP64` for the ILP64
 interface), an alias is added to the alias file.
 
-The linker option is injected into the Reference LAPACK configure process using
-the `CMAKE_EXE_LINKER_FLAGS` variable for the test compiles and the
-`CMAKE_SHARED_LINKER_FLAGS` variable for the shared LAPACKE library.
+The additional linker options get attached to new interface library targets,
+which are injected into the Reference LAPACK configure process using the
+`CMAKE_REQUIRED_LIBRARIES` variable for the Fortran test compiles and the
+`LINK_LIBRARIES` target property for the shared LAPACKE library.
 
 This enables the compilation of the LAPACKE C-interface library for the
 Accelerate framework (e. g. to be used in the `Eigen3` library). Analyzing
@@ -113,9 +116,9 @@ the resulting `.dylib` with `otool`, you can see:
 ```shell
 $ otool -L ./build/32/_deps/reference-lapack-build/lib/liblapacke.dylib
 ./build/32/_deps/reference-lapack-build/lib/liblapacke.dylib:
-    @rpath/liblapacke.3.dylib (compatibility version 3.0.0, current version 3.9.1)
+    @rpath/liblapacke.3.dylib (compatibility version 3.0.0, current version 3.11.0)
     /System/Library/Frameworks/Accelerate.framework/Versions/A/Accelerate (compatibility version 1.0.0, current version 4.0.0)
-    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1336.61.1)
+    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1351.0.0)
 ```
 
 Only the Accelerate framework and the System library are linked into the
@@ -127,6 +130,8 @@ After the CMake configuration, the alias files can be found in `./build/<32|64>/
 
 ```plaintext
 ./build/<32|64>/src
+├── new-blas-ilp64.alias
+├── new-blas.alias
 ├── new-lapack-ilp64.alias
 └── new-lapack.alias
 ```
@@ -141,7 +146,7 @@ other compilers installed on your system, make sure CMake finds the correct one.
 Otherwise, help CMake by setting the environment variable `$ export
 CC=/usr/bin/cc` in your terminal window.
 
-It is also recommended to use at least CMake v3.20 with presets, but the CMake
+It is also recommended to use at least CMake v3.25 with presets, but the CMake
 script also works down to CMake v3.12, if you set the required variables on the
 command line.
 
@@ -178,10 +183,11 @@ or `/opt/local` (used by MacPorts).
 
 #### CMake v4 compatibility ####
 
-To build the project with CMake v4 or higher, there is a `cmake4` preset, that
-you can use in your `CMakeUserPresets.json`. Both `user-accelerate-lapacke32`
-and `user-accelerate-lapacke64` should additionally inherit from `cmake4`. This
-is not included by default.
+To build the project with CMake v4 or higher, you must explicitly provide the
+`CMAKE_OSX_SYSROOT` variable in your `CMakeUserPresets.json`. Both the
+`user-accelerate-lapacke32` and `user-accelerate-lapacke64` presets should
+additionally have the cache variable `"CMAKE_OSX_SYSROOT": "macosx"`. This is
+not included by default.
 
 ### Using LAPACKE in another project ###
 

src/CMakeLists.txt

@@ -42,50 +42,137 @@ build_aliases(BLAS_NEWLAPACK_ILP64_SYMBOLS)
 build_aliases(LAPACK_NEWLAPACK_SYMBOLS)
 build_aliases(LAPACK_NEWLAPACK_ILP64_SYMBOLS)
 
-file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/new-lapack.alias"
-"\
-# BLAS
-
-${BLAS_NEWLAPACK_ALIASES}
+configure_file(
+    "${CMAKE_CURRENT_SOURCE_DIR}/new-blas.alias.in"
+    "${CMAKE_CURRENT_BINARY_DIR}/new-blas.alias"
+    @ONLY
+)
 
-# LAPACK
+configure_file(
+    "${CMAKE_CURRENT_SOURCE_DIR}/new-lapack.alias.in"
+    "${CMAKE_CURRENT_BINARY_DIR}/new-lapack.alias"
+    @ONLY
+)
 
-${LAPACK_NEWLAPACK_ALIASES}
-"
+configure_file(
+    "${CMAKE_CURRENT_SOURCE_DIR}/new-blas-ilp64.alias.in"
+    "${CMAKE_CURRENT_BINARY_DIR}/new-blas-ilp64.alias"
+    @ONLY
 )
 
-file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/new-lapack-ilp64.alias"
-"\
-# BLAS
+configure_file(
+    "${CMAKE_CURRENT_SOURCE_DIR}/new-lapack-ilp64.alias.in"
+    "${CMAKE_CURRENT_BINARY_DIR}/new-lapack-ilp64.alias"
+    @ONLY
+)
 
-${BLAS_NEWLAPACK_ILP64_ALIASES}
+add_library(NEW_BLAS INTERFACE IMPORTED GLOBAL)
+target_link_libraries(NEW_BLAS INTERFACE ${BLAS_LIBRARIES})
 
-# LAPACK
+add_library(NEW_LAPACK INTERFACE IMPORTED GLOBAL)
+target_link_libraries(NEW_LAPACK INTERFACE ${LAPACK_LIBRARIES} NEW_BLAS)
 
-${LAPACK_NEWLAPACK_ILP64_ALIASES}
-"
+# Add the $NEWLAPACK symbols to the linker flags of the NEW_BLAS and NEW_LAPACK
+# targets
+target_link_options(
+    NEW_BLAS
+    INTERFACE
+    ${BLAS_LINKER_FLAGS}
+    "LINKER:-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-blas.alias"
+)
+target_link_options(
+    NEW_LAPACK
+    INTERFACE
+    ${LAPACK_LINKER_FLAGS}
+    "LINKER:-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-lapack.alias"
 )
 
-# Set configuration options for Reference LAPACK
-set(BUILD_SHARED_LIBS ON CACHE BOOL "")
-set(CBLAS OFF CACHE BOOL "")
-set(LAPACKE ON CACHE BOOL "")
+add_library(NEW_BLAS64 INTERFACE IMPORTED GLOBAL)
+target_link_libraries(NEW_BLAS64 INTERFACE ${BLAS_LIBRARIES})
+
+add_library(NEW_LAPACK64 INTERFACE IMPORTED GLOBAL)
+target_link_libraries(NEW_LAPACK64 INTERFACE ${LAPACK_LIBRARIES} NEW_BLAS64)
 
-# Add the $NEWLAPACK symbols to the linker flags used in try_compile()
-set(CMAKE_EXE_LINKER_FLAGS "-framework Accelerate -Wl,-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-lapack.alias")
+# Add the $NEWLAPACK$ILP64 symbols to the linker flags of the NEW_BLAS64 and
+# NEW_LAPACK64 targets
+target_link_options(
+    NEW_BLAS64
+    INTERFACE
+    ${BLAS_LINKER_FLAGS}
+    "LINKER:-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-blas-ilp64.alias"
+)
+target_link_options(
+    NEW_LAPACK64
+    INTERFACE
+    ${LAPACK_LINKER_FLAGS}
+    "LINKER:-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-lapack-ilp64.alias"
+)
 
 if (BUILD_INDEX64)
-    # Add the $NEWLAPACK$ILP64 symbols to the linker flags used for shared libraries
-    set(CMAKE_SHARED_LINKER_FLAGS "-framework Accelerate -Wl,-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-lapack-ilp64.alias")
+    # Add the $NEWLAPACK$ILP64 symbols to the BLAS and LAPACK libraries.
+    set(BLAS_LIBRARIES "NEW_BLAS64")
+    set(LAPACK_LIBRARIES "NEW_LAPACK64")
+    set(CHECK_LAPACK_VERSION_SOURCE "${CMAKE_CURRENT_SOURCE_DIR}/lapack64_version.c")
 else ()
-    # Add the $NEWLAPACK symbols to the linker flags used for shared libraries
-    set(CMAKE_SHARED_LINKER_FLAGS "-framework Accelerate -Wl,-alias_list,${CMAKE_CURRENT_BINARY_DIR}/new-lapack.alias")
+    # Add the $NEWLAPACK symbols to the linker flags of the lapacke target
+    set(BLAS_LIBRARIES "NEW_BLAS")
+    set(LAPACK_LIBRARIES "NEW_LAPACK")
+    set(CHECK_LAPACK_VERSION_SOURCE "${CMAKE_CURRENT_SOURCE_DIR}/lapack_version.c")
 endif ()
 
+set_target_properties(BLAS::BLAS PROPERTIES INTERFACE_LINK_LIBRARIES "${BLAS_LIBRARIES}")
+set_target_properties(LAPACK::LAPACK PROPERTIES INTERFACE_LINK_LIBRARIES "${LAPACK_LIBRARIES}")
+
+try_run(
+    HAS_RUN_ILAVER HAS_ILAVER
+    SOURCES ${CHECK_LAPACK_VERSION_SOURCE}
+    LINK_LIBRARIES ${LAPACK_LIBRARIES}
+    RUN_OUTPUT_VARIABLE ACCELERATE_LAPACK_ILAVER_VERSION
+)
+
+message(STATUS "The BLAS/LAPACK version provided by the Accelerate framework is confirmed to be: ${ACCELERATE_LAPACK_ILAVER_VERSION}")
+
 FetchContent_Declare(
     reference-lapack
     GIT_REPOSITORY "https://github.com/Reference-LAPACK/lapack.git"
     GIT_TAG "v${ACCELERATE_NEW_LAPACK_VERSION}"
 )
 
+# Set configuration options for Reference LAPACK
+set(BUILD_SHARED_LIBS ON CACHE BOOL "")
+set(CBLAS OFF CACHE BOOL "")
+set(LAPACKE ON CACHE BOOL "")
+
+if (CMAKE_VERSION VERSION_GREATER_EQUAL 4)
+    # CMake deprecated all CMake versions prior to v3.5. The relevant Reference
+    # LAPACK versions still use v3.2, which leads to an error, unless we
+    # override this:
+    set(ENV{CMAKE_POLICY_VERSION_MINIMUM} 3.5)
+endif ()
+
+set(BLAS_LIBRARIES_BACKUP "${BLAS_LIBRARIES}")
+set(LAPACK_LIBRARIES_BACKUP "${LAPACK_LIBRARIES}")
+
+# Set the BLAS and LAPACK libraries to the new 32bit targets. This helps the
+# Reference LAPACK CMake script to pass the CheckFortranFunctionExists tests for
+# `dgemm` and `dgeqrt`.
+set(BLAS_LIBRARIES "NEW_BLAS")
+set(LAPACK_LIBRARIES "NEW_LAPACK")
+
 FetchContent_MakeAvailable(reference-lapack)
+
+# Restore BLAS and LAPACK libraries to what they were before (32bit or 64bit)
+set(BLAS_LIBRARIES "${BLAS_LIBRARIES_BACKUP}")
+set(LAPACK_LIBRARIES "${LAPACK_LIBRARIES_BACKUP}")
+
+if (CMAKE_VERSION VERSION_GREATER_EQUAL 4)
+    unset(ENV{CMAKE_POLICY_VERSION_MINIMUM})
+endif ()
+
+if (BUILD_INDEX64)
+    # Replace the LINK_LIBRARIES of the lapacke64 target with the ILP64 ones.
+    # The lapacke64 target was created linking to the NEW_LAPACK target, which
+    # we had to add to satisfy the Check... tests, that the Reference LAPACK
+    # build script does.
+    set_target_properties(lapacke64 PROPERTIES LINK_LIBRARIES "${LAPACK_LIBRARIES}")
+endif ()

src/lapack64_version.c

+/*
+ * MIT License
+ *
+ * CMake build script for the Accelerate LAPACKE project
+ * Copyright (c) 2025 Tim Kaune
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stdio.h>
+
+extern void ilaver_(long int* major, long int* minor, long int* patch);
+
+int main()
+{
+    long int major, minor, patch;
+    ilaver_(&major, &minor, &patch);
+    printf("LAPACK v%ld.%ld.%ld", major, minor, patch);
+    return 0;
+}

src/lapack_version.c

+/*
+ * MIT License
+ *
+ * CMake build script for the Accelerate LAPACKE project
+ * Copyright (c) 2025 Tim Kaune
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stdio.h>
+
+extern void ilaver_(int* major, int* minor, int* patch);
+
+int main()
+{
+    int major, minor, patch;
+    ilaver_(&major, &minor, &patch);
+    printf("LAPACK v%d.%d.%d", major, minor, patch);
+    return 0;
+}

src/new-blas-ilp64.alias.in

+# BLAS
+
+@BLAS_NEWLAPACK_ILP64_ALIASES@

src/new-blas.alias.in

+# BLAS
+
+@BLAS_NEWLAPACK_ALIASES@

src/new-lapack-ilp64.alias.in

+# LAPACK
+
+@LAPACK_NEWLAPACK_ILP64_ALIASES@

src/new-lapack.alias.in

+# LAPACK
+
+@LAPACK_NEWLAPACK_ALIASES@