update darwin_arm64_gfortran to be able to use free-format f90 files (M…

…ITgcm#879) * add "-x f95 -ffree-form" to F90FLAGS does not hurt, but is necessary for any free-format code * document updating 1 optfile to compile F90 files --------- Co-authored-by: Jean-Michel Campin <[email protected]>
jahn · Oct 17, 2024 · c7a06a2 · c7a06a2
1 parent 5bb179d
commit c7a06a2
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Showing 2 changed files with 7 additions and 2 deletions.
diff --git a/doc/tag-index b/doc/tag-index
@@ -1,7 +1,9 @@
     Notes on tags used in MITgcmUV
     ==============================
 
-o pkg/seaice: 
+o tools/build_options:
+  - update darwin_arm64_gfortran to be able to compile free-format F90 files.
+o pkg/seaice:
   - add new lateral drag parameterisation for landfast ice (Liu etal 2022, JGR)
 o verification/*/results:
   - update 5 adm + 3 tlm ref. output affected by TAF new version 6.4.5 & 6.5.0

diff --git a/tools/build_options/darwin_arm64_gfortran b/tools/build_options/darwin_arm64_gfortran
@@ -73,7 +73,10 @@ else
     fi
 fi
 
-F90FLAGS=$FFLAGS
+# add undocumented flag -x f95 to force gfortran to interpret any
+# suffix as a f90-freeformat file, add -ffree-form to suppress the
+# associated warning
+F90FLAGS="$FFLAGS -x f95 -ffree-form"
 F90OPTIM=$FOPTIM
 
 INCLUDEDIRS=''