[Patch, Fortan] Depricate -M<dir> in favour of -J<dir>

[Tobias Burnus <burnus at net-b dot de>]

Daniel pointed out in IRC that we should deprecate the -M<dir> option as 
we want eventually use -M to generate Makefile items (as GCC does, see 
"man gcc").

The PR regarding using -M for makefiles is PR31588.

The attached patch does:
- Mark -M as deprecated in invoke.texi
- Change error message texts from "-M" to "-J"
- Fix an ICE if "-M" without argument has been specified as last argument
- Fix using "-M<dir>" - before only "-M <dir>" was working
- Print a warning that -M is deprecated

Currently, -J<dir> is supported while -J <dir> is not. I will fix this 
after the regression-only period; a patch can be found in PR 35019.

Build and regtested on x86-64-linux.
OK for the trunk (4.3.0)?

Tobias
2008-01-29  Tobias Burnus  <burnus@net-b.de>

	PR fortran/31588
	* gfortranspec.c (lang_specific_driver): Deprecate -M option;
	if ICE when "-M" is last argument and make "-M<dir>" work.
	* options.c (gfc_handle_module_path_options): Use -J instead
	of -M in error messages.
	* invoke.c: Mark -M as depecated.

Index: gcc/fortran/gfortranspec.c
===================================================================
--- gcc/fortran/gfortranspec.c	(revision 131933)
+++ gcc/fortran/gfortranspec.c	(working copy)
@@ -426,7 +426,9 @@ For more information about these matters
 	{
 	  char *p;
 
-	  if (argv[i][2] == '\0')
+	  fprintf (stderr, _("Warning: Using -M <directory> is deprecated, "
+	           "use -J instead\n"));
+	  if (argv[i][2] == '\0' && i+1 < argc)
 	    {
 	      p = XNEWVEC (char, strlen (argv[i + 1]) + 2);
 	      p[0] = '-';
@@ -437,7 +439,9 @@ For more information about these matters
 	  else
 	    {
 	      p = XNEWVEC (char, strlen (argv[i]) + 1);
-	      strcpy (p, argv[i]);
+	      p[0] = '-';
+	      p[1] = 'J';
+	      strcpy (&p[2], argv[i]);
 	    }
 	  append_arg (p);
 	  continue;
Index: gcc/fortran/options.c
===================================================================
--- gcc/fortran/options.c	(revision 131933)
+++ gcc/fortran/options.c	(working copy)
@@ -389,13 +389,13 @@ gfc_handle_module_path_options (const ch
 
   if (gfc_option.module_dir != NULL)
     {
-      gfc_status ("gfortran: Only one -M option allowed\n");
+      gfc_status ("gfortran: Only one -J option allowed\n");
       exit (3);
     }
 
   if (arg == NULL)
     {
-      gfc_status ("gfortran: Directory required after -M\n");
+      gfc_status ("gfortran: Directory required after -J\n");
       exit (3);
     }
 
Index: gcc/fortran/invoke.texi
===================================================================
--- gcc/fortran/invoke.texi	(revision 131933)
+++ gcc/fortran/invoke.texi	(working copy)
@@ -627,8 +627,8 @@ compiled modules are required by a @code
 gcc,Using the GNU Compiler Collection (GCC)}, for information on the
 @option{-I} option.
 
-@item -M@var{dir}
 @item -J@var{dir}
+@item -M@var{dir}
 @opindex @code{M}@var{dir}
 @opindex @code{J}@var{dir}
 @cindex paths, search
@@ -639,8 +639,7 @@ statement.
 
 The default is the current directory.
 
-@option{-J} is an alias for @option{-M} to avoid conflicts with existing
-GCC options.
+Note: @option{-M} is deprecated to avoid conflicts with existing GCC options.
 
 @item -fintrinsic-modules-path @var{dir}
 @opindex @code{fintrinsic-modules-path} @var{dir}