cmake 2023 updates

[loriab]

• update old files

  • copy over xhost.cmake that has new compilers. import it instead of one-liner. adapt if C, not CXX.
    • No, since mostly fortran
  • expand safeguards to new build types, RelWithDebInfo, and MinSizeRel
  • update cmake min version to 3.16
  • replace SameMajorVersion with now-available SameMinorVersion if appropriate
    • AnyNewVersion -> SameMajorVersion
  • remove any ${PN} in main project CMake as they tend to get clobbered in/after find_package
  • any new project-specific options, prepend in project-case, like ambit_ENABLE_PYTHON. does not apply to e.g., BUILD_TESTING, BUILD_SHARED_LIBS

• Python

  • if still on old NumPy/pb11 Py detection, switch to approx. find_package(Python 3.7 COMPONENTS Interpreter Development NumPy REQUIRED)
  • update any set(Python_ADDITIONAL_VERSIONS
  • update cmake_minimum_required(VERSION 3.16) for Py detection
  • update any PYTHON_EXECUTABLE to Python_EXECUTABLE
  • remove any old FindPythonLibsNew.cmake
  • if any pybind11, check that find_package(Python) before find_package(pybind11)
  • if any pybind11 target, remove PREFIX/SUFFIX from properties
  • psi4: update the call in external/

• editable config.cmake location

  • add option(<project>_INSTALL_CMAKEDIR) to make Config.cmake location editable with variable, incl any subprojects like TargetLAPACK.
  • recipe: specify in bld.bat as -D <project>_INSTALL_CMAKEDIR="Library\share\cmake\<project>" ^ if CMAKE_INSTALL_PREFIX="%PREFIX%"
  • psi4: add the call in external/ (CMAKE_ARGS and <project>_DIR and any TargetLAPACK, etc.)

• modernize target install/export

  • for install(TARGETS), use full runtime/arch/lib DESTINATIONs so Windows can work
  • for install(TARGETS), consider a descriptive EXPORT so not repeating targets filename
  • for install(EXPORT), use descriptive EXPORT and lang or type names to Targets files

• make properties target-centered, particularly for FetchContent usage. target and find_package(<package>) should provide same info.

  • define export_properties variable and append it to all base targets (e.g., static and shared always-built libs)
  • set the version on the target. use casing like in the config file, probaly project(CheMPS2) --> CheMPS2_VERSION
  • set all other properties that were project-specific vars in the config (like Libint_MAX_AM_ERI) on the target
  • check through find_package() that targets are fully loaded (--log-level verbose and extra stuff in Config.cmake can help)
  • define aliases matching imported targets, add_library(ambit::ambit ALIAS ambit-shared). Favor shared if both can be built together.
  • rename any CMAKE_SOURCE_DIR/CMAKE_BINARY_DIR to PROJECT_SOURCE_DIR/PROJECT_BINARY_DIR
  • check fetch_content works

• modernize <project>Config.cmake.in

  • kill off all PN with something like set(amb ambit) # NameSpace. PN gets overwritten a lot, so let's specialize it.
  • remove find_header, find_file, find_library find_exe reminicent of Find<project>.cmake rather than <project>Config.cmake
  • read find_project variables off target, rather than setting from file_header/lib/exe results
  • if any Find files installed, add list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR})
  • check components with check_required_components(<project>) (probably already present)
  • NEVER load exported <project>Targets.cmake before all components confirmed found and all dependencies confirmed found
  • run a find_project(<project>) to check that vars match target (same as 4th bullet prev. section)

• check that all dependencies are handled (sometimes outsourced to psi4, like BLAS for dkh)

  • add TargetLAPACK if using BLAS/LAPACK
  • copy over new FindTargetLAPACK, FindTargetHDF5 as needed. modify if only use BLAS
  • install the Find files with the Config
  • in config file, add any find_dependency that we were leaving for psi4 before

• handling lib and pylib as separate projects

  • there's room for opinion on this. see discussion at GH:jturney/ambit/pyambit/CMakeLists.txt .
  • YES, do have an ENABLE_PYTHON (or better, _ENABLE_PYTHON) so library can be built alone
  • PROBABLY YES, do have a project(pyproject) so python can be built alone after detecting project
  • CHOOSING YES, do have a ambit_PYMOD variable attached to the target and Config?
  • CHOOSING YES, same Config.cmake file for C++ and Py, where latter optional and detected with COMPONENTS Python? It's easy enough to have the targets exported to Targets-Python.cmake so same file can manage.
  • details on separate pylib
    • for installation positioning, use PYMOD_INSTALL_LIBDIR if var already exists b/c in psi orbit. otherwise emulate libint (LIBINT2_INSTALL_PYMODDIR) or libxc (PYLIBXC_INSTALL_PYMODDIR)
    • copy over basic and relevant options from main project
    • copy over version from main project. notate where to sync verson
      notes for packagers about config.cmake
    • install whole py intf module, incl tests
    • remove restriction that pb11 module can only link to shared library. remove PIC for pb11 module since it handles that
    • for Linux-style install ONLY, write a Python component to Config.cmake
    • if a Py-style install is wanted, toggle Linux-style and Py-style install with something like LIBINT2_PREFIX_PYTHON_INSTALL
    • leave a note for packagers about lib/pylib and config.cmake choices

• particular for this project: gdma

  • add executable back
  • add py module
  • add windows