Do not run MPI Fortran tests on Ubuntu Artful.

test cases/frameworks/17 mpi/is_artful.py

@@ -0,0 +1,9 @@
+#!/usr/bin/env python3
+
+# Any exception causes return value to be not zero, which is sufficient.
+
+import sys
+
+fc = open('/etc/apt/sources.list').read()
+if 'artful' not in fc:
+    sys.exit(1)

test cases/frameworks/17 mpi/meson.build

@@ -23,7 +23,15 @@ if build_machine.system() != 'windows'
   test('MPI C++', execpp)
 endif
 
-if add_languages('fortran', required : false)
+# OpenMPI is broken with Fortran on Ubuntu Artful.
+# Remove this once the following bug has been fixed:
+#
+# https://bugs.launchpad.net/ubuntu/+source/gcc-defaults/+bug/1727474
+
+ubudetector = find_program('is_artful.py')
+uburesult = run_command(ubudetector)
+
+if uburesult.returncode() != 0 and add_languages('fortran', required : false)
   mpifort = dependency('mpi', language : 'fortran')
   exef = executable('exef',
     'main.f90',