mpich-gcc12 @4.1.2_0+fortran: cmake no longer locates MPI_C and MPI_CXX (but still finds MPI_Fortran OK)

[floquet-cxx]

The application I'm compiling/developing uses C++, C, F77 and MPI. It has compiled and run fine for many years, though it's still in development. I was recently forced to "upgrade" from Ventura to Sonoma (14.2.1) and Xcode15 and now MPI_C and MPI_CXX can't be found by cmake (worked fine before the "upgrade"). Problem now happens on both ARM M2 macs I have. I did a clean reinstall if macports and all the ports I use.

I'm not completely sure the issue is with mpich, but it doesn't occur with openmpi, so I am assuming it's an mpich port issue as opposed to a cmake port issue. Though I'm using gcc12, the same problem occurs with gcc13.

Here are the commands I use to install gcc12 and mpich (on both Ventura and Sonoma)

  sudo port -N install cmake
  sudo port -N install gcc12
  sudo port -N install mpich-gcc12
  sudo port select --set mpi mpich-gcc12-fortran

I require the MPI package with cmake for this application. I believe this means that MPI_C, MPI_CXX and MPI_Fortran will be required as linkers - even though the top-level code is C++, some lower-level libraries in my application use C and F77. So here are the errors I now get when cmake is run:

build (master) >$ cmake ..
-- The C compiler identification is AppleClang 15.0.0.15000100
-- The CXX compiler identification is AppleClang 15.0.0.15000100
-- The Fortran compiler identification is GNU 12.3.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Checking whether Fortran compiler has -isysroot
-- Checking whether Fortran compiler has -isysroot - yes
-- Checking whether Fortran compiler supports OSX deployment target flag
-- Checking whether Fortran compiler supports OSX deployment target flag - yes
-- Detecting Fortran compiler ABI info
-- Detecting Fortran compiler ABI info - done
-- Check for working Fortran compiler: /opt/local/bin/gfortran - skipped
-- Building with Apple Accelerate BLAS and LAPACK.
-- Building code with standard release optimizations.
-- Found BISON: /opt/local/bin/bison (found version "3.8.2") 
-- Looking for Fortran sgemm
-- Looking for Fortran sgemm - found
-- Found BLAS: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk/usr/lib/libblas.tbd  
-- Looking for Fortran cheev
-- Looking for Fortran cheev - found
-- Found LAPACK: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk/usr/lib/liblapack.tbd;/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk/usr/lib/libblas.tbd  
-- Could NOT find MPI_C (missing: MPI_C_WORKS) 
-- Could NOT find MPI_CXX (missing: MPI_CXX_WORKS) 
-- Found MPI_Fortran: /opt/local/lib/mpich-gcc12/libmpifort.dylib (found version "4.0") 
CMake Error at /opt/local/share/cmake-3.24/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
  Could NOT find MPI (missing: MPI_C_FOUND MPI_CXX_FOUND) (found version
  "4.0")
Call Stack (most recent call first):
  /opt/local/share/cmake-3.24/Modules/FindPackageHandleStandardArgs.cmake:594 (_FPHSA_FAILURE_MESSAGE)
  /opt/local/share/cmake-3.24/Modules/FindMPI.cmake:1835 (find_package_handle_standard_args)
  CMakeLists.txt:100 (find_package)

-- Configuring incomplete, errors occurred!
See also "/Users/hmb/develop-git/semtex-master/build/CMakeFiles/CMakeOutput.log".
See also "/Users/hmb/develop-git/semtex-master/build/CMakeFiles/CMakeError.log".

Perhaps related: you can see that Apple's C and C++ compilers are selected, but GNU's Fortran compiler gets selected. However, this combination has worked in the past.

I looks like the cmake MPI package resolver has a conflict with the version numbers of libmpicxx and libmpi although they are apparently consistent with libmpifort (all 4.0).

Here is a listing of what is in /opt/local/lib/mpich-gcc12:

build (master) >$ ls /opt/local/lib/mpich-gcc12/
libfmpich.dylib@        libmpicxx.12.dylib*     libopa.dylib@
libmpi.12.dylib*        libmpicxx.a             libpmpi.12.dylib*
libmpi.a                libmpicxx.dylib@        libpmpi.a
libmpi.dylib@           libmpifort.12.dylib*    libpmpi.dylib@
libmpich.dylib@         libmpifort.a            pkgconfig/
libmpichcxx.dylib@      libmpifort.dylib@
libmpichf90.dylib@      libmpl.dylib@

[floquet-cxx]

I find that if I force the use of Macports gcc and g++ compilers on the command line, like so:

cmake -DCMAKE_C_COMPILER=/opt/local/bin/gcc -DCMAKE_CXX_COMPILER=/opt/local/bin/g++ ..

then the cmake errors go away, and compilation completes (instead, mpirun now fails!). However, the original code (both with/without Apple C and C++ compilers) still works fine on pre-Sonoma OS X versions.

[floquet-cxx]

Sorry - I forgot to enter that the port concerned is mpich.

[floquet-cxx]

Resolved. Installed port mpich-default +gcc12.