BerkeleyLab · bonachea · Sep 15, 2026 · Sep 13, 2026 · Sep 14, 2026 · Sep 14, 2026
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -65,6 +65,11 @@ jobs:
             container: snowstep/llvm:ubuntu-22.04-latest
 
           # https://hub.docker.com/r/phhargrove/llvm-flang/tags
+          - os: ubuntu-24.04-arm
+            compiler: flang
+            version: 23
+            container: phhargrove/llvm-flang:23.1.0-latest-arm64
+
           - os: ubuntu-24.04
             compiler: flang
             version: 23
@@ -133,10 +138,6 @@ jobs:
             compiler: lfortran
             version: 0.62.0
             container: phhargrove/lfortran:0.62.0-1
-          - os: ubuntu-24.04
-            compiler: lfortran
-            version: 0.63.0
-            container: phhargrove/lfortran:0.63.0-1
 
           # https://github.com/lfortran/lfortran/pkgs/container/lfortran
           - os: ubuntu-22.04
@@ -151,6 +152,10 @@ jobs:
             compiler: lfortran
             version: 0.65.0
             container: ghcr.io/lfortran/lfortran:v0.65.0
+          - os: ubuntu-22.04
+            compiler: lfortran
+            version: 0.66.0
+            container: ghcr.io/lfortran/lfortran:v0.66.0
           - os: ubuntu-22.04
             compiler: lfortran
             version: latest
@@ -248,12 +253,12 @@ jobs:
           echo "FPM_FC=ifx" >> "$GITHUB_ENV"
           if [[ "$COMPILER_VERSION" = "latest-coarray" ]] ; then
             echo "FOR_COARRAY_NUM_IMAGES=4" >> "$GITHUB_ENV"
-            echo "FFLAGS=-coarray -fpp -g -traceback $FFLAGS" >> "$GITHUB_ENV"
+            echo "FFLAGS=-coarray -g -traceback $FFLAGS" >> "$GITHUB_ENV"
             #echo "FOR_COARRAY_MPI_VERBOSE=1" >> "$GITHUB_ENV"
             #echo "FOR_COARRAY_DEBUG_STARTUP=1" >> "$GITHUB_ENV"
           else
             # issue #162: ifx coarray support is usually disabled because it hides runtime failures
-            echo "FFLAGS=-DHAVE_MULTI_IMAGE_SUPPORT=0 -fpp -g -traceback $FFLAGS" >> "$GITHUB_ENV"
+            echo "FFLAGS=-DHAVE_MULTI_IMAGE_SUPPORT=0 -g -traceback $FFLAGS" >> "$GITHUB_ENV"
           fi
         elif test "$FC" = "lfortran" ; then
           echo "FPM_FC=lfortran" >> "$GITHUB_ENV"
@@ -278,10 +283,11 @@ jobs:
       if: ${{ runner.os == 'Linux' && runner.arch == 'ARM64' }}
       run: |
         export FPM_VERSION=0.13.0
+        mkdir -p fpm-temp/bin
+        cd fpm-temp
         curl --retry 5 -LOsS https://github.com/fortran-lang/fpm/releases/download/v$FPM_VERSION/fpm-$FPM_VERSION.F90
-        mkdir fpm-temp
-        gfortran-14 -o fpm-temp/fpm fpm-$FPM_VERSION.F90
-        echo "PATH=`pwd`/fpm-temp:${PATH}" >> "$GITHUB_ENV"
+        gfortran-14 -o bin/fpm fpm-$FPM_VERSION.F90
+        echo "PATH=$PWD/bin:${PATH}" >> "$GITHUB_ENV"
 
     - name: Version info
       run: |

diff --git a/README.md b/README.md
@@ -200,19 +200,22 @@ With `fpm` versions older than 0.13.0, replace `flang` with `flang-new` below.
 
 Compiler/Runtime  |Tested Versions|Run Type|Example build/test commands (parallel examples use 2 images)
 ------------------|---------------|--------|------------------------------------------------------------
-LLVM/[Caffeine]   |22             |parallel|`fpm test --compiler flang --flag "-O3 -DHAVE_MULTI_IMAGE_SUPPORT -fcoarray" --link-flag "-lcaffeine -lgasnet-smp-seq -L<caffeine-prefix>/lib"`
+LLVM/[Caffeine]   |22             |parallel|`fpm test --compiler flang --flag "-O3 -DHAVE_MULTI_IMAGE_SUPPORT -fcoarray -DASSERT_MULTI_IMAGE" --link-flag "-lcaffeine -lgasnet-smp-seq -L<caffeine-prefix>/lib"` (\*)
 LLVM              |20-22          |serial  |`fpm test --compiler flang --flag -O3`
 LLVM              |19 (+)         |serial  |`fpm test --compiler flang --flag "-O3 -mmlir -allow-assumed-rank"`
 GCC/[OpenCoarrays]|14-15          |parallel|`fpm test --compiler caf --runner "cafrun -n 2" --profile release`
 GCC/[OpenCoarrays]|13             |parallel|`fpm test --compiler caf --runner "cafrun -n 2" --profile release --flag -ffree-line-length-none`
 GCC               |14-16          |serial  |`fpm test --compiler gfortran --profile release`
 GCC               |13             |serial  |`fpm test --compiler gfortran --profile release --flag -ffree-line-length-none`
-Intel             |2025.2-2026.0  |parallel|`FOR_COARRAY_NUM_IMAGES=2 fpm test --compiler ifx --flag "-fpp -O3 -coarray" --profile release`
+Intel             |2025.2-2026.0  |parallel|`FOR_COARRAY_NUM_IMAGES=2 fpm test --compiler ifx --flag "-O3 -coarray" --profile release`
 LFortran          |0.61-0.63      |serial  |`fpm test --compiler lfortran --flag "--cpp --realloc-lhs-arrays --separate-compilation"`
-NAG               |7.2 (-)        |parallel|`NAGFORTRAN_NUM_IMAGES=2 fpm test --compiler nagfor --flag "-O4 -fpp -coarray"`
+NAG               |7.2 (-)        |parallel|`NAGFORTRAN_NUM_IMAGES=2 fpm test --compiler nagfor --flag "-O1 -coarray"`
 
-(+) Support for LLVM flang version 19 is deprecated, and may be removed in a future release.
-(-) Using NAG on macOS requires an `fpm` installation containing [PR 1312](https://github.com/fortran-lang/fpm/pull/1312)
+> (\*) Additional linker options might be required depending on platform. 
+On Linux, it may be necessary to prepend `-Wl,--start-group` to `--link-flag`, or manually add the libraries
+to fpm.toml.    
+> (+) Support for LLVM flang version 19 is deprecated, and may be removed in a future release.    
+> (-) Using NAG on macOS requires an `fpm` installation containing [PR 1312](https://github.com/fortran-lang/fpm/pull/1312)    
 
 The test output reports a test as skipped if there is a known issue that blocks
 the tested feature with the chosen compiler version or platform.  Due to a

diff --git a/demo/src/specimen_m.f90 → demo/src/specimen_m.F90 b/demo/src/specimen_m.f90 → demo/src/specimen_m.F90
diff --git a/demo/src/widget_m.f90 → demo/src/widget_m.F90 b/demo/src/widget_m.f90 → demo/src/widget_m.F90
diff --git a/demo/test/driver.f90 → demo/test/driver.F90 b/demo/test/driver.f90 → demo/test/driver.F90
diff --git a/demo/test/specimen_test_m.f90 → demo/test/specimen_test_m.F90 b/demo/test/specimen_test_m.f90 → demo/test/specimen_test_m.F90
diff --git a/demo/test/widget_test_m.f90 → demo/test/widget_test_m.F90 b/demo/test/widget_test_m.f90 → demo/test/widget_test_m.F90
diff --git a/...rsing/check-for-command-line-argument.f90 → ...rsing/check-for-command-line-argument.F90 b/...rsing/check-for-command-line-argument.f90 → ...rsing/check-for-command-line-argument.F90
diff --git a/...e-parsing/get-command-line-flag-value.f90 → ...e-parsing/get-command-line-flag-value.F90 b/...e-parsing/get-command-line-flag-value.f90 → ...e-parsing/get-command-line-flag-value.F90
diff --git a/example/pure-printing/pure-stop-and-print.F90 b/example/pure-printing/pure-stop-and-print.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2026, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 program pure_stop_and_print
 #if HAVE_STOP_AND_PRINT_SUPPORT

diff --git a/example/pure-printing/write_stuff_m.F90 b/example/pure-printing/write_stuff_m.F90
@@ -1,10 +1,10 @@
 ! Copyright (c) 2024-2026, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
-#if HAVE_STOP_AND_PRINT_SUPPORT
 module write_stuff_m
+#if HAVE_STOP_AND_PRINT_SUPPORT
   !! Demonstrate a derived type that is writable to a stop  via Julienne's stop_and_print utility
   use julienne_m, only : writable_t
   implicit none
@@ -27,6 +27,7 @@ module subroutine write_formatted(self, unit, edit_descriptor, v_list, iostat, i
     end subroutine
 
   end interface
-
-end module
+#else
+  EMPTY_MODULE_ANCESTOR
 #endif
+end module
diff --git a/example/pure-printing/write_stuff_s.F90 b/example/pure-printing/write_stuff_s.F90
@@ -1,10 +1,10 @@
 ! Copyright (c) 2024-2026, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
-#if HAVE_STOP_AND_PRINT_SUPPORT
 submodule(write_stuff_m) write_stuff_s
+#if HAVE_STOP_AND_PRINT_SUPPORT
   implicit none
 
 contains
@@ -16,6 +16,7 @@
     write(unit,'(a)'     ) "}" // new_line('')
     iostat = 0
   end procedure
-
-end submodule
+#else
+  EMPTY_MODULE_SUBMODULE
 #endif
+end submodule
diff --git a/fpm.toml b/fpm.toml
@@ -1,7 +1,7 @@
 name = "julienne"
 
 [dependencies]
-assert = {git = "https://github.com/berkeleylab/assert", tag = "3.1.2"}
+assert = {git = "https://github.com/berkeleylab/assert", tag = "3.2.0"}
 
 [install]
 library = true
diff --git a/include/language-support.F90 → include/julienne-language-support.F90 b/include/language-support.F90 → include/julienne-language-support.F90
@@ -63,4 +63,8 @@
 #  endif
 #endif
 
+! Incantation to allow a conforming empty module and submodule
+#define EMPTY_MODULE_ANCESTOR private ; interface ; module subroutine dummy ; end subroutine ; end interface
+#define EMPTY_MODULE_SUBMODULE contains ; module procedure dummy ; end procedure
+
 #endif
diff --git a/src/julienne/julienne_assert_m.f90 → src/julienne/julienne_assert_m.F90 b/src/julienne/julienne_assert_m.f90 → src/julienne/julienne_assert_m.F90
diff --git a/src/julienne/julienne_assert_s.f90 → src/julienne/julienne_assert_s.F90 b/src/julienne/julienne_assert_s.f90 → src/julienne/julienne_assert_s.F90
diff --git a/src/julienne/julienne_bin_m.f90 → src/julienne/julienne_bin_m.F90 b/src/julienne/julienne_bin_m.f90 → src/julienne/julienne_bin_m.F90
diff --git a/src/julienne/julienne_command_line_m.f90 → src/julienne/julienne_command_line_m.F90 b/src/julienne/julienne_command_line_m.f90 → src/julienne/julienne_command_line_m.F90
diff --git a/src/julienne/julienne_command_line_s.F90 b/src/julienne/julienne_command_line_s.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2026, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 submodule(julienne_command_line_m) julienne_command_line_s
   implicit none

diff --git a/src/julienne/julienne_file_m.f90 → src/julienne/julienne_file_m.F90 b/src/julienne/julienne_file_m.f90 → src/julienne/julienne_file_m.F90
diff --git a/src/julienne/julienne_github_ci_m.f90 → src/julienne/julienne_github_ci_m.F90 b/src/julienne/julienne_github_ci_m.f90 → src/julienne/julienne_github_ci_m.F90
diff --git a/src/julienne/julienne_github_ci_s.f90 → src/julienne/julienne_github_ci_s.F90 b/src/julienne/julienne_github_ci_s.f90 → src/julienne/julienne_github_ci_s.F90
diff --git a/src/julienne/julienne_multi_image_m.F90 b/src/julienne/julienne_multi_image_m.F90
@@ -51,22 +51,22 @@ function julienne_this_image_interface() result(this_image_id)
         integer :: this_image_id
       end function
     end interface
-    procedure(julienne_this_image_interface), pointer :: julienne_this_image
+    procedure(julienne_this_image_interface), pointer :: julienne_this_image => null()
 
     abstract interface
       function julienne_num_images_interface() result(image_count)
         implicit none
         integer :: image_count
       end function
     end interface
-    procedure(julienne_num_images_interface), pointer :: julienne_num_images
+    procedure(julienne_num_images_interface), pointer :: julienne_num_images => null()
 
     abstract interface
       subroutine julienne_sync_all_interface()
         implicit none
       end subroutine
     end interface
-    procedure(julienne_sync_all_interface), pointer :: julienne_sync_all
+    procedure(julienne_sync_all_interface), pointer :: julienne_sync_all => null()
 
     abstract interface
       subroutine julienne_co_sum_integer_interface(a, result_image)
@@ -75,15 +75,15 @@ subroutine julienne_co_sum_integer_interface(a, result_image)
         integer, intent(in), optional :: result_image
       end subroutine
     end interface
-    procedure(julienne_co_sum_integer_interface), pointer :: julienne_co_sum_integer
+    procedure(julienne_co_sum_integer_interface), pointer :: julienne_co_sum_integer => null()
 
     abstract interface
       pure subroutine julienne_error_stop_interface(stop_code_char)
         implicit none
         character(len=*), intent(in) :: stop_code_char
       end subroutine
     end interface
-    procedure(julienne_error_stop_interface), pointer :: julienne_error_stop
+    procedure(julienne_error_stop_interface), pointer :: julienne_error_stop => null()
 #endif
 
 

diff --git a/src/julienne/julienne_multi_image_s.F90 b/src/julienne/julienne_multi_image_s.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 #include "assert_macros.h"
 
 submodule(julienne_multi_image_m) julienne_multi_image_s
@@ -46,7 +46,7 @@
       if (associated(julienne_sync_all)) then
         call julienne_sync_all()
       else
-        ; ! assume single-image, no-op
+         ! assume single-image, no-op
         call_assert(internal_num_images() == 1)
       end if
 #   else 
@@ -61,7 +61,7 @@
       if (associated(julienne_co_sum_integer)) then
         call julienne_co_sum_integer(a, result_image)
       else
-        ; ! assume single-image, no-op
+         ! assume single-image, no-op
         call_assert(internal_num_images() == 1)
       end if
 #   else 
@@ -79,7 +79,7 @@
       if (associated(julienne_error_stop)) then
         call julienne_error_stop(stop_code_char)
       else
-        ; ! deliberate fall-thru
+        ! deliberate fall-thru
       end if
 #   endif
     error stop stop_code_char

diff --git a/src/julienne/julienne_stop_and_print_m.F90 b/src/julienne/julienne_stop_and_print_m.F90
@@ -1,11 +1,10 @@
 ! Copyright (c), The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
-
-#if HAVE_STOP_AND_PRINT_SUPPORT
+#include "julienne-language-support.F90"
 
 module julienne_stop_and_print_m
+#if HAVE_STOP_AND_PRINT_SUPPORT
   !! Define a pure subroutine that formats and prints various data types during error termination
   use julienne_string_m, only : string_t
   implicit none
@@ -66,6 +65,7 @@ pure module function character_stop_code(stuff) result(stop_code)
     end function
 
   end interface
-
-end module julienne_stop_and_print_m
+#else
+  EMPTY_MODULE_ANCESTOR
 #endif
+end module julienne_stop_and_print_m
diff --git a/src/julienne/julienne_stop_and_print_s.F90 b/src/julienne/julienne_stop_and_print_s.F90
@@ -1,11 +1,10 @@
 ! Copyright (c), The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
-
-#if HAVE_STOP_AND_PRINT_SUPPORT
+#include "julienne-language-support.F90"
 
 submodule(julienne_stop_and_print_m) julienne_stop_and_print_s
+#if HAVE_STOP_AND_PRINT_SUPPORT
   use julienne_string_m, only : operator(.csv.), operator(.separatedBy.)
   use julienne_file_m, only : file_t
   use julienne_multi_image_m, only : internal_error_stop
@@ -187,7 +186,7 @@ pure subroutine stop_and_print_header_data_footer(data, header, footer)
         end associate
     end select
   end procedure
-
-end submodule julienne_stop_and_print_s
-
+#else 
+  EMPTY_MODULE_SUBMODULE
 #endif
+end submodule julienne_stop_and_print_s
diff --git a/src/julienne/julienne_test_description_m.f90 → src/julienne/julienne_test_description_m.F90 b/src/julienne/julienne_test_description_m.f90 → src/julienne/julienne_test_description_m.F90
diff --git a/src/julienne/julienne_test_description_s.F90 b/src/julienne/julienne_test_description_s.F90
@@ -3,7 +3,7 @@
 
 #include "julienne-assert-macros.h"
 #include "assert_macros.h"
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 submodule(julienne_test_description_m) julienne_test_description_s
   use assert_m

diff --git a/src/julienne/julienne_test_diagnosis_m.F90 b/src/julienne/julienne_test_diagnosis_m.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 module julienne_test_diagnosis_m
   !! Define abstractions, defined operations, and procedures for writing correctness checks

diff --git a/src/julienne/julienne_test_diagnosis_s.F90 b/src/julienne/julienne_test_diagnosis_s.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 #include "assert_macros.h"
 
 submodule(julienne_test_diagnosis_m) julienne_test_diagnosis_s

diff --git a/src/julienne/julienne_test_fixture_m.f90 → src/julienne/julienne_test_fixture_m.F90 b/src/julienne/julienne_test_fixture_m.f90 → src/julienne/julienne_test_fixture_m.F90
diff --git a/src/julienne/julienne_test_harness_m.f90 → src/julienne/julienne_test_harness_m.F90 b/src/julienne/julienne_test_harness_m.f90 → src/julienne/julienne_test_harness_m.F90
diff --git a/src/julienne/julienne_test_harness_s.F90 b/src/julienne/julienne_test_harness_s.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 submodule(julienne_test_harness_m) julienne_test_harness_s
   use iso_fortran_env, only : int64, real64

diff --git a/src/julienne/julienne_test_m.F90 b/src/julienne/julienne_test_m.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 module julienne_test_m
   !! Define an abstract test_t type with deferred bindings ("subject" and "results")

diff --git a/src/julienne/julienne_test_result_m.f90 → src/julienne/julienne_test_result_m.F90 b/src/julienne/julienne_test_result_m.f90 → src/julienne/julienne_test_result_m.F90
diff --git a/src/julienne/julienne_test_result_s.F90 b/src/julienne/julienne_test_result_s.F90
@@ -2,7 +2,7 @@
 ! Terms of use are as specified in LICENSE.txt
 
 #include "julienne-assert-macros.h"
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 submodule(julienne_test_result_m) julienne_test_result_s
 #if ASSERTIONS

diff --git a/src/julienne/julienne_test_s.F90 b/src/julienne/julienne_test_s.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 submodule(julienne_test_m) julienne_test_s
   use julienne_test_description_m, only : filter

diff --git a/src/julienne/julienne_test_suite_m.f90 → src/julienne/julienne_test_suite_m.F90 b/src/julienne/julienne_test_suite_m.f90 → src/julienne/julienne_test_suite_m.F90
diff --git a/src/julienne_m.F90 b/src/julienne_m.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 module julienne_m
   !! Global aggregation of all public entities

diff --git a/test/driver.F90 b/test/driver.F90
@@ -1,7 +1,7 @@
 ! Copyright (c) 2024-2025, The Regents of the University of California and Sourcery Institute
 ! Terms of use are as specified in LICENSE.txt
 
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 program test_suite_driver
   !! Julienne test-suite driver

diff --git a/test/idiomatic_assertion_failure_test.F90 b/test/idiomatic_assertion_failure_test.F90
@@ -2,7 +2,7 @@
 ! Terms of use are as specified in LICENSE.txt
 
 #include "julienne-assert-macros.h"
-#include "language-support.F90"
+#include "julienne-language-support.F90"
 
 program idiomatic_assertion_failure_test
   !! Conditionally test an assertion that is hardwired to fail.