Let configure logic instead of test code deal with defect tests.

config/checksrc/test_mpi_pack_external_1.c

@@ -40,7 +40,6 @@ int main(int argc, char **argv) {
   }
   MPI_Aint position = 0;
 
-#ifndef WITHOUT_PACK_EXTERNAL
 #define BUG
 #ifdef BUG
   mpi_err_handler(MPI_Pack_external(datarep, uint_data, UINT_COUNT,
@@ -57,7 +56,6 @@ int main(int argc, char **argv) {
                                     MPI_UNSIGNED, pack_buffer, pack_size,
                                     &position), MPI_COMM_WORLD);
 #endif // NO_BUG
-#endif // WITHOUT_PACK_EXTERNAL
 
   free(pack_buffer);
   free(dble_data);

config/checksrc/test_mpi_pack_external_2.c

@@ -12,8 +12,6 @@ int main(void) {
 
   MPI_Init(NULL, NULL);
 
-#ifndef WITHOUT_PACK_EXTERNAL
-
   int send_data[2] = {93184, -9023};
   int recv_data[2];
 
@@ -35,8 +33,6 @@ int main(void) {
   if ((send_data[0] != recv_data[0]) || (send_data[1] != recv_data[1]))
     exit_code = EXIT_FAILURE;
 
-#endif // WITHOUT_PACK_EXTERNAL
-
   MPI_Finalize();
 
   return exit_code;

configure.ac

@@ -72,13 +72,19 @@ AS_IF([test x"$enable_MPI" = xyes],
    AC_ARG_WITH([mpi-pack-external],
      [AS_HELP_STRING([--without-mpi-pack-external],
         [use MPI_Pack (not guaranteed to work) instead of MPI_Pack_external @<:@default: yes, use MPI_Pack_external@:>@])],,[with_mpi_pack_external=yes])
-   AS_IF([test x"$with_mpi_pack_external" = xyes],,
+   AS_IF([test x"$with_mpi_pack_external" != xyes],
      [CPPFLAGS="${CPPFLAGS+$CPPFLAGS }-DWITHOUT_PACK_EXTERNAL"])
    ACX_MPI_DEFECTS(,,
-     [ACX_MPI_DEFECTS_DOCUMENT
-      AS_CASE(["$acx_subtestname"],[test_mpi_pack_external_*],[AC_MSG_FAILURE])
-      AS_IF([test "$with_regard_for_quality" != no],
-        [AC_MSG_FAILURE([test for known defect $subtestname failed, re-configure with --without-regard-for-quality in case you must use the given MPI implementation, but some tests might fail])])])
+     [AS_CASE(["$CPPFLAGS$acx_subtestname"],
+        [*-DWITHOUT_PACK_EXTERNAL*test_mpi_pack_external_*],
+        [AS_IF([test x"$acx_mpi_defects_result" = xerror],
+           [acx_mpi_defects_result='error (work-around active)'])],
+        [AS_IF([test "$with_regard_for_quality" != no],
+           [AC_MSG_RESULT([$acx_mpi_defects_result])
+            ACX_MPI_DEFECTS_DOCUMENT
+            AC_MSG_FAILURE([test for known defect $acx_subtestname failed, re-configure with --without-regard-for-quality in case you must use the given MPI implementation, but some tests might fail])],
+           [AS_IF([test x"$acx_mpi_defects_result" = xerror],
+              [acx_mpi_defects_result='error (suppressed)'])])])])
 AS_IF([test "x$MPI_LAUNCH" = xtrue],
   [AC_MSG_WARN([MPI launch command unavailable])])
 FCFLAGS=$saved_FCFLAGS

m4/acx_mpi_defects.m4

@@ -104,14 +104,15 @@ q
              [acx_mpirun_test=`echo "$ac_link" | sed -e 's@\(.*/libtool --mode=\)link.*@\1@'`"execute $acx_mpirun_test"])
 	   _AC_RUN_LOG_LIMIT([LIBC_FATAL_STDERR_=1 $acx_mpirun_num_tasks >&2],[echo "running $acx_mpirun_num_tasks"])
 	   AS_IF([test $ac_status -eq 0],
-	     [AC_MSG_RESULT([okay])m4_ifval([$2],[
-	      $2])],
-	     [AC_MSG_RESULT([error])
-	      m4_ifval([$3],[$3],
-	        [AC_MSG_FAILURE([chosen MPI has known error $acx_subtestname])])])],
-	  [AC_MSG_RESULT([error])
-	   m4_ifval([$3],[$3],
-	     [AC_MSG_RESULT([chosen MPI has known error $acx_subtestname])])])
+	     [acx_mpi_defects_result=okay; acx_mpi_defects_fail=no]m4_ifval([$2],[
+	      $2]),
+	     [acx_mpi_defects_result=error
+              m4_ifval([$3],[$3], [acx_mpi_defects_fail=yes])])],
+	  [acx_mpi_defects_result=error
+           m4_ifval([$3],[$3],[acx_mpi_defects_fail=yes])])
+        AC_MSG_RESULT([$acx_mpi_defects_result])
+        AS_IF([test x"$acx_mpi_defects_fail" = xyes],
+          [AC_MSG_FAILURE([chosen MPI has known error $acx_subtestname])])
 	AS_CASE([$acx_suffix],
 	  [f90|F90],[AC_LANG_POP([Fortran])],
 	  [c],[AC_LANG_POP([C])])])