Issue with installation

[stefgeorgiadis96]

Hi,
I'm trying to install clawpack using 'pip install clawpack' and I get the error message below. Do you know what might be wrong and how to fix it?

Collecting clawpack
Using cached clawpack-5.9.2.tar.gz (5.8 MB)
Installing build dependencies ... done
Getting requirements to build wheel ... done
Installing backend dependencies ... done
Preparing metadata (pyproject.toml) ... error
error: subprocess-exited-with-error

× Preparing metadata (pyproject.toml) did not run successfully.
│ exit code: 1
╰─> [13 lines of output]
+ meson setup /private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755 /private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755/.mesonpy-r40rmv2m -Dbuildtype=release -Db_ndebug=if-release -Db_vscrt=md --native-file=/private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755/.mesonpy-r40rmv2m/meson-python-native-file.ini
The Meson build system
Version: 1.3.1
Source dir: /private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755
Build dir: /private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755/.mesonpy-r40rmv2m
Build type: native build
Program python3 found: YES (/Users/georgis/anaconda3/bin/python3)
Project name: clawpack
Project version: 5.9.2

  ../meson.build:1:0: ERROR: Compiler gfortran cannot compile programs.
  
  A full log can be found at /private/var/folders/58/zphccs7s5xl_p23crs7s7g2wn3yt1j/T/pip-install-1f0r90ia/clawpack_a299fda99b9546e98a80dfadec192755/.mesonpy-r40rmv2m/meson-logs/meson-log.txt
  [end of output]

note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

note: This is an issue with the package mentioned above, not pip.
hint: See above for details.

[mandli]

The primary error is that your Fortran compiler does not seem to work. In principle you can use PyClaw without the Fortran compiler but I am not sure how the meson build handles that.

[ketch]

I found someone had a similar issue here:

mesonbuild/meson#12282

They were also using homebrew to install gfortran, and it sounds like there is a bug with some particular version of gfortran. From the thread there, you could try doing

export LDFLAGS="$LDFLAGS -Wl,-ld_classic"

before the clawpack install. If that doesn't work, I suggest installing a different fortran compiler. I recommend using one from this site:

https://github.com/fxcoudert/gfortran-for-macOS/releases

[cpraveen]

I have not had to do anything special on my macs. Probably I reinstalled gcc/gfortran from brew after the upgrade to clang15, you should try that.

You can also create a conda env, install gfortran via conda inside that env, and then pip install clawpack.