GILDAS build fail on Big Sur / arm64

[rampante]

I've been trying to install gildas on macOS Big Sur 11.4 (Xcode version 12.5, M1 chip) without success:

• at first I got a "ld: framework not found CoreFoundation" error. Following ​this ticket, I reinstalled gcc11 and python38 from source
• now, on the other hand, this warning appears:

  -->  Found 3 broken files, matching files to ports
  --->  Found 1 broken port, determining rebuild order
  You can always run 'port rev-upgrade' again to fix errors.
  The following ports will be rebuilt: gildas @202107a+gcc11
  

and, after a few of attempts, the build is still broken. Running port -d -y rev-upgrade yields the following output.