Various cleanups to help compile server.

	* line-map.c (add_line_map):  Allow leaving the outermost file.
	Allowing entering an outermost-file after the initial time.

	* toplev.c (pop_srcloc):  Allow popping from initial file.

From-SVN: r64616

gcc/ChangeLog

+2003-03-20  Per Bothner  <pbothner@apple.com>
+
+	Various cleanups to help compile server.
+
+	* line-map.c (add_line_map):  Allow leaving the outermost file.
+	Allowing entering an outermost-file after the initial time. 
+
+	* toplev.c (pop_srcloc):  Allow popping from initial file.
+
 2003-03-20  Kazu Hirata  <kazu at cs dot umass dot edu>
 
 	* fold-const.c (fold): Fold A - (A & B) into ~B & A.

gcc/line-map.c

@@ -106,9 +106,9 @@ add_line_map (set, reason, sysp, from_line, to_file, to_line)
 
       if (MAIN_FILE_P (map - 1))
 	{
-	  error = true;
-	  reason = LC_RENAME;
-	  from = map - 1;
+	  set->depth--;
+	  set->used--;
+	  return NULL;
 	}
       else
 	{
@@ -139,8 +139,8 @@ add_line_map (set, reason, sysp, from_line, to_file, to_line)
 
   if (reason == LC_ENTER)
     {
+      map->included_from = set->depth == 0 ? -1 : (int) (set->used - 2);
       set->depth++;
-      map->included_from = set->used - 2;
       if (set->trace_includes)
 	trace_include (set, map);
     }

gcc/toplev.c

@@ -2166,11 +2166,17 @@ pop_srcloc ()
   input_file_stack = fs->next;
   free (fs);
   input_file_stack_tick++;
-  /* The initial source file is never popped.  */
-  if (!input_file_stack)
-    abort ();
-  input_filename = input_file_stack->name;
-  lineno = input_file_stack->line;
+
+  if (input_file_stack)
+    {
+      input_filename = input_file_stack->name;
+      lineno = input_file_stack->line;
+    }
+  else
+    {
+      input_filename = NULL;
+      lineno = 0;
+    }
 }
 
 /* Compile an entire translation unit.  Write a file of assembly