1 files changed, 107 insertions, 2 deletions

diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index b6121db..c980499 100644
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -42,7 +42,7 @@ unsigned int
 gfc_init_options (unsigned int argc ATTRIBUTE_UNUSED,
 		  const char **argv ATTRIBUTE_UNUSED)
 {
-  gfc_option.source = NULL;
+  gfc_source_file = NULL;
   gfc_option.module_dir = NULL;
   gfc_option.source_form = FORM_UNKNOWN;
   gfc_option.fixed_line_length = 72;
@@ -71,6 +71,7 @@ gfc_init_options (unsigned int argc ATTRIBUTE_UNUSED,
   gfc_option.flag_pack_derived = 0;
   gfc_option.flag_repack_arrays = 0;
   gfc_option.flag_backslash = 1;
+  gfc_option.flag_d_lines = -1;
 
   gfc_option.q_kind = gfc_default_double_kind;
 
@@ -89,6 +90,74 @@ gfc_init_options (unsigned int argc ATTRIBUTE_UNUSED,
 }
 
 
+/* Determine the source form from the filename extension.  We assume
+   case insensitivity.  */
+
+static gfc_source_form
+form_from_filename (const char *filename)
+{
+
+  static const struct
+  {
+    const char *extension;
+    gfc_source_form form;
+  }
+  exttype[] =
+  {
+    {
+    ".f90", FORM_FREE}
+    ,
+    {
+    ".f95", FORM_FREE}
+    ,
+    {
+    ".f", FORM_FIXED}
+    ,
+    {
+    ".for", FORM_FIXED}
+    ,
+    {
+    "", FORM_UNKNOWN}
+  };		/* sentinel value */
+
+  gfc_source_form f_form;
+  const char *fileext;
+  int i;
+
+  /* Find end of file name.  Note, filename is either a NULL pointer or
+     a NUL terminated string.  */
+  i = 0;
+  while (filename[i] != '\0')
+    i++;
+
+  /* Find last period.  */
+  while (i >= 0 && (filename[i] != '.'))
+    i--;
+
+  /* Did we see a file extension?  */
+  if (i < 0)
+    return FORM_UNKNOWN; /* Nope  */
+
+  /* Get file extension and compare it to others.  */
+  fileext = &(filename[i]);
+
+  i = -1;
+  f_form = FORM_UNKNOWN;
+  do
+    {
+      i++;
+      if (strcasecmp (fileext, exttype[i].extension) == 0)
+	{
+	  f_form = exttype[i].form;
+	  break;
+	}
+    }
+  while (exttype[i].form != FORM_UNKNOWN);
+
+  return f_form;
+}
+
+
 /* Finalize commandline options.  */
 
 bool
@@ -102,7 +171,35 @@ gfc_post_options (const char **pfilename)
       filename = "";
     }
 
-  gfc_option.source = filename;
+  gfc_source_file = filename;
+
+  /* Decide which form the file will be read in as.  */
+
+  if (gfc_option.source_form != FORM_UNKNOWN)
+    gfc_current_form = gfc_option.source_form;
+  else
+    {
+      gfc_current_form = form_from_filename (filename);
+
+      if (gfc_current_form == FORM_UNKNOWN)
+	{
+	  gfc_current_form = FORM_FREE;
+	  gfc_warning_now ("Reading file '%s' as free form.", 
+			   (filename[0] == '\0') ? "<stdin>" : filename); 
+	}
+    }
+
+  /* If the user specified -fd-lines-as-{code|comments} verify that we're
+     in fixed form.  */
+  if (gfc_current_form == FORM_FREE)
+    {
+      if (gfc_option.flag_d_lines == 0)
+	gfc_warning_now ("'-fd-lines-as-comments' has no effect "
+			 "in free form.");
+      else if (gfc_option.flag_d_lines == 1)
+	gfc_warning_now ("'-fd-lines-as-code' has no effect "
+			 "in free form.");
+    }
 
   flag_inline_trees = 1;
 
@@ -238,6 +335,14 @@ gfc_handle_option (size_t scode, const char *arg, int value)
       gfc_option.flag_backslash = value;
       break;
 
+    case OPT_fd_lines_as_code:
+      gfc_option.flag_d_lines = 1;
+      break;
+
+    case OPT_fd_lines_as_comments:
+      gfc_option.flag_d_lines = 0;
+      break;
+
     case OPT_fdump_parse_tree:
       gfc_option.verbose = value;
       break;