fftw-3 does not configure with +gfortran (Catalina, Xcode 10.3, Macports-2.6.1)

[nombak]

% port install fftw-3 +gfortran+openmpi
--->  Configuring fftw-3
Error: openmpi-default has a different Fortran variant () than the one selected, gcc9 (via +gfortran).
Error: Failed to configure fftw-3: Install openmpi-default +gcc9
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_www.macports.org_files_ports_math_fftw-3/fftw-3/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
Error: Processing of port fftw-3 failed

Following the message,

% port deactivate openmpi-default
% port install openmpi-default +gcc9

Then, tried again

% port install fftw-3 +gfortran+openmpi

, which surprisingly, deactivated the newly installed "openmpi-default +gcc9" (contrary to its own message), and activated the old "openmpi-default", which resulted in the same error.

[jmroot (Joshua Root)]

You need to be using Xcode 11.x on Catalina, but there are also unresolved issues with gcc.

[nombak]

Yes, that's why I'd like to stick to Xcode 10 on Catalina.
Any workaround to this issue?

[cjones051073 (Chris Jones)]

gcc9 is fine on macOS 10.15 with Xcode 11.1. Using Xcode 10 is not supported, so yes please update then report back.

[nombak]

libgcc9 still fails in my environment; macOS 10.15.1 beta1, Xcode 11.2 beta2, and MacPorts 2.6.1.

[cjones051073 (Chris Jones)]

Have you filed a ticket for libgcc9, as that is not expected.

[cjones051073 (Chris Jones)]

You are still installing openmpi-default with the wrong variant. i.e.

port install openmpi-default +gcc9

if you want to use the gfortran variant with fftw-3, that needs to be

port install openmpi-default +gfortran

however..... the above variant does not exist.

Basically this means the variants +gfortran and +openmpi cannot be used at the same time with fftw-3.

I recommend instead using the variant gcc9, which is the default with openmpi.