Update known compiler switches for Fortran and OpenMP macros.

[Ralf Wildenhues]

This patch is my current known set of updates for existing Fortran
macros.  Most of the switches are taken from manuals only (I don't
really have access to that many compilers), so there might still be
bugs.  I plan to ask a couple of people with other Fortran compilers
once my patch queue is fairly flushed; it is simpler to just fix all
fallout at once then.

When some compiler lists more than just one flag, that might be due
to different versions of the compiler, or to just alternate spellings.
Since the latter often results from the former, I typically chose to
try all variants.  The Lahey single and double dash flags are for
w32 and GNU/Linux, respectively (at least that is what the manuals
imply).

I'm pushing this, as indicated by Eric, although of course I always
welcome any review.

Thanks,
Ralf

    Update known compiler switches for Fortran and OpenMP macros.
    
    * lib/autoconf/c.m4 (AC_OPENMP): Update for Lahey on GNU/Linux.
    * lib/autoconf/fortran.m4 (_AC_F95_FC): Also try nagfor.
    (_AC_PROG_FC_V): Update documentation for Lahey switches.
    (AC_FC_FREEFORM, AC_FC_FIXEDFORM): Add flags for Absoft, Lahey
    on GNU/Linux, document NAGWare, g95, and f2c switches.
    (AC_FC_LINE_LENGTH): Document NAGware switch.  Update Absoft,
    Lahey, NAGWare, Open Watcom, g95, and f2c switches.

diff --git a/lib/autoconf/c.m4 b/lib/autoconf/c.m4
index 89e6b49..e4b807b 100644
--- a/lib/autoconf/c.m4
+++ b/lib/autoconf/c.m4
@@ -2001,12 +2001,14 @@ AC_DEFUN([AC_OPENMP],
          dnl   IBM C (AIX, Linux)   -qsmp=omp
           dnl   Cray CCE             -homp
           dnl   NEC SX               -Popenmp
+          dnl   Lahey Fortran (Linux)  --openmp
          dnl If in this loop a compiler is passed an option that it doesn't
          dnl understand or that it misinterprets, the AC_LINK_IFELSE test
          dnl will fail (since we know that it failed without the option),
          dnl therefore the loop will continue searching for an option, and
          dnl no output file called 'penmp' or 'mp' is created.
-         for ac_option in -fopenmp -xopenmp -openmp -mp -omp -qsmp=omp -homp 
-Popenmp; do
+         for ac_option in -fopenmp -xopenmp -openmp -mp -omp -qsmp=omp -homp \
+                           -Popenmp --openmp; do
            ac_save_[]_AC_LANG_PREFIX[]FLAGS=$[]_AC_LANG_PREFIX[]FLAGS
            _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $ac_option"
            AC_LINK_IFELSE([_AC_LANG_OPENMP],
diff --git a/lib/autoconf/fortran.m4 b/lib/autoconf/fortran.m4
index d5afbb9..30544c4 100644
--- a/lib/autoconf/fortran.m4
+++ b/lib/autoconf/fortran.m4
@@ -316,7 +316,8 @@ AC_DEFUN([_AC_FC_DIALECT_YEAR],
 #  fort: Compaq (now HP) Fortran 90/95 compiler for Tru64 and Linux/Alpha
 #  ifort, previously ifc: Intel Fortran 95 compiler for Linux/x86
 #  efc: Intel Fortran 95 compiler for IA64
-m4_define([_AC_F95_FC], [gfortran g95 xlf95 f95 fort ifort ifc efc pgfortran 
pgf95 lf95 ftn])
+#  nagfor: NAGWare Fortran 77/90/95 compiler
+m4_define([_AC_F95_FC], [gfortran g95 xlf95 f95 fort ifort ifc efc pgfortran 
pgf95 lf95 ftn nagfor])
 m4_define([_AC_F90_FC], [xlf90 f90 pgf90 pghpf epcf90])
 m4_define([_AC_F77_FC], [g77 xlf f77 frt pgf77 cf77 fort77 fl32 af77])
 AC_DEFUN([_AC_PROG_FC],
@@ -564,7 +565,7 @@ esac
 # Determine the flag that causes the Fortran compiler to print
 # information of library and object files (normally -v)
 # Needed for _AC_FC_LIBRARY_FLAGS
-# Some compilers don't accept -v (Lahey: -verbose, xlf: -V, Fujitsu: -###)
+# Some compilers don't accept -v (Lahey: (-)-verbose, xlf: -V, Fujitsu: -###)
 AC_DEFUN([_AC_PROG_FC_V],
 [_AC_FORTRAN_ASSERT()dnl
 AC_CACHE_CHECK([how to get verbose linking output from $[]_AC_FC[]],
@@ -1179,15 +1180,17 @@ AC_LANG_POP(Fortran)dnl
 # prevent flag from being added to FCFLAGS multiple times.)
 #
 # The known flags are:
-#        -ffree-form: GNU g77, gfortran
+#        -ffree-form: GNU g77, gfortran, g95
 #         -FR, -free: Intel compiler (icc, ecc, ifort)
 #              -free: Compaq compiler (fort), Sun compiler (f95)
 #             -qfree: IBM compiler (xlf)
 # -Mfree, -Mfreeform: Portland Group compiler
 #          -freeform: SGI compiler
-#            -f free: Absoft Fortran
+#        -8, -f free: Absoft Fortran
 #       +source=free: HP Fortran
-#              -nfix: Lahey/Fujitsu Fortran
+#    (-)-nfix, -Free: Lahey/Fujitsu Fortran
+#              -free: NAGWare
+#         -f, -Wf,-f: f2c (but only a weak form of "free-form" and long lines)
 # We try to test the "more popular" flags first, by some prejudiced
 # notion of popularity.
 AC_DEFUN_ONCE([AC_FC_FREEFORM],
@@ -1197,7 +1200,7 @@ AC_CACHE_CHECK([for Fortran flag needed to accept 
free-form source],
 [ac_cv_fc_freeform=unknown
 ac_fc_freeform_FCFLAGS_save=$FCFLAGS
 for ac_flag in none -ffree-form -FR -free -qfree -Mfree -Mfreeform \
-              -freeform "-f free" +source=free -nfix
+              -freeform "-f free" -8 +source=free -nfix --nfix -Free
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_freeform_FCFLAGS_save $ac_flag"
 dnl Use @&t@ below to ensure that editors don't turn 8+ spaces into tab.
@@ -1235,14 +1238,15 @@ AC_LANG_POP([Fortran])dnl
 # prevent flag from being added to FCFLAGS multiple times.)
 #
 # The known flags are:
-#       -ffixed-form: GNU g77, gfortran
+#       -ffixed-form: GNU g77, gfortran, g95
 #             -fixed: Intel compiler (ifort), Sun compiler (f95)
 #            -qfixed: IBM compiler (xlf*)
 #            -Mfixed: Portland Group compiler
 #         -fixedform: SGI compiler
 #           -f fixed: Absoft Fortran
 #      +source=fixed: HP Fortran
-#              -fix: Lahey/Fujitsu Fortran
+#    (-)-fix, -Fixed: Lahey/Fujitsu Fortran
+#             -fixed: NAGWare
 # Since compilers may accept fixed form based on file name extension,
 # but users may want to use it with others as well, call AC_FC_SRCEXT
 # with the respective source extension before calling this macro.
@@ -1253,7 +1257,7 @@ AC_CACHE_CHECK([for Fortran flag needed to accept 
fixed-form source],
 [ac_cv_fc_fixedform=unknown
 ac_fc_fixedform_FCFLAGS_save=$FCFLAGS
 for ac_flag in none -ffixed-form -fixed -qfixed -Mfixed -fixedform "-f fixed" \
-              +source=fixed -fix
+              +source=fixed -fix --fix -Fixed
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_fixedform_FCFLAGS_save $ac_flag"
   AC_COMPILE_IFELSE([[
@@ -1296,6 +1300,7 @@ AC_LANG_POP([Fortran])dnl
 # The known flags are:
 # -f{free,fixed}-line-length-N with N 72, 80, 132, or 0 or none for none.
 # -ffree-line-length-none: GNU gfortran
+# -ffree-line-length-huge: g95 (also -ffixed-line-length-N as above)
 #       -qfixed=132 80 72: IBM compiler (xlf)
 #                -Mextend: Cray
 #            -132 -80 -72: Intel compiler (ifort)
@@ -1303,11 +1308,14 @@ AC_LANG_POP([Fortran])dnl
 #                          accepts that as well with an optional parameter and
 #                          doesn't fail but only warns about unknown arguments.
 #          -extend_source: SGI compiler
-#     -W NN (132, 80, 72): Absoft Fortran
-#          +extend_source: HP Fortran (254 in either form, default is 72 fixed,
+#  -W, -WNN (132, 80, 72): Absoft Fortran
+#     +es, +extend_source: HP Fortran (254 in either form, default is 72 fixed,
 #                         132 free)
-#                   -wide: Lahey/Fujitsu Fortran (255 cols in fixed form)
+#            -w, (-)-wide: Lahey/Fujitsu Fortran (255 cols in fixed form)
 #                      -e: Sun Fortran compiler (132 characters)
+#                    -132: NAGWare
+#         -72, -f, -Wf,-f: f2c (a weak form of "free-form" and long lines).
+#                  /XLine: Open Watcom
 AC_DEFUN_ONCE([AC_FC_LINE_LENGTH],
 [AC_LANG_PUSH([Fortran])dnl
 m4_case(m4_default([$1], [132]),
@@ -1332,11 +1340,13 @@ AC_CACHE_CHECK(
 ac_fc_line_length_FCFLAGS_save=$FCFLAGS
 for ac_flag in none \
               -ffree-line-length-none -ffixed-line-length-none \
+              -ffree-line-length-huge \
               -ffree-line-length-$ac_fc_line_len \
               -ffixed-line-length-$ac_fc_line_len \
               -qfixed=$ac_fc_line_len -Mextend \
               -$ac_fc_line_len -extend_source \
-              "-W $ac_fc_line_len" +extend_source -wide -e
+              -W$ac_fc_line_len -W +extend_source +es -wide --wide -w -e \
+               -f -Wf,-f -xline
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_line_length_FCFLAGS_save 
$ac_flag"
   AC_COMPILE_IFELSE([[$ac_fc_line_length_test