tm.texi (DRIVER_SELF_SPECS): Document.

	* doc/tm.texi (DRIVER_SELF_SPECS): Document.
	* gcc.c (driver_self_specs): New variable.
	(do_self_spec): New function.
	(main): Use it to process driver_self_specs.

From-SVN: r58109

gcc/ChangeLog

+2002-10-14  Richard Sandiford  <rsandifo@redhat.com>
+
+	* doc/tm.texi (DRIVER_SELF_SPECS): Document.
+	* gcc.c (driver_self_specs): New variable.
+	(do_self_spec): New function.
+	(main): Use it to process driver_self_specs.
+
 2002-10-13  Richard Henderson  <rth@redhat.com>
 
 	* rtl.c (shallow_copy_rtx): Use memcpy for the entire node.

gcc/doc/tm.texi

@@ -163,6 +163,23 @@ multilibs.  Example nonsensical definition, where @code{-malt-abi},
 @{ "-compat", "-EB -malign=4 -mspoo" @}
 @end smallexample
 
+@findex DRIVER_SELF_SPECS
+@item DRIVER_SELF_SPECS
+A list of specs for the driver itself.  It should be a suitable
+initializer for an array of strings, with no surrounding braces.
+
+The driver applies these specs to its own command line before choosing
+the multilib directory or running any subcommands.  It applies them in
+the order given, so each spec can depend on the options added by
+earlier ones.  It is also possible to remove options using
+@samp{%<@var{option}} in the usual way.
+
+This macro can be useful when a port has several interdependent target
+options.  It provides a way of standardizing the command line so
+that the other specs are easier to write.
+
+Do not define this macro if it does not need to do anything.
+
 @findex CPP_SPEC
 @item CPP_SPEC
 A C string constant that tells the GCC driver program options to

gcc/gcc.c

@@ -296,6 +296,7 @@ static char *save_string	PARAMS ((const char *, int));
 static void set_collect_gcc_options PARAMS ((void));
 static int do_spec_1		PARAMS ((const char *, int, const char *));
 static int do_spec_2		PARAMS ((const char *));
+static void do_self_spec	PARAMS ((const char *));
 static const char *find_file	PARAMS ((const char *));
 static int is_directory		PARAMS ((const char *, const char *, int));
 static void validate_switches	PARAMS ((const char *));
@@ -738,6 +739,12 @@ static const char *multilib_exclusions;
 
 static const char *const multilib_defaults_raw[] = MULTILIB_DEFAULTS;
 
+#ifndef DRIVER_SELF_SPECS
+#define DRIVER_SELF_SPECS ""
+#endif
+
+static const char *const driver_self_specs[] = { DRIVER_SELF_SPECS };
+
 struct user_specs
 {
   struct user_specs *next;
@@ -4268,6 +4275,45 @@ do_spec_2 (spec)
   return do_spec_1 (spec, 0, NULL);
 }
 
+
+/* Process the given spec string and add any new options to the end
+   of the switches/n_switches array.  */
+
+static void
+do_self_spec (spec)
+     const char *spec;
+{
+  do_spec_2 (spec);
+  do_spec_1 (" ", 0, NULL);
+
+  if (argbuf_index > 0)
+    {
+      int i, first;
+
+      first = n_switches;
+      n_switches += argbuf_index;
+      switches = xrealloc (switches,
+			   sizeof (struct switchstr) * (n_switches + 1));
+
+      switches[n_switches] = switches[first];
+      for (i = 0; i < argbuf_index; i++)
+	{
+	  struct switchstr *sw;
+
+	  /* Each switch should start with '-'.  */
+	  if (argbuf[i][0] != '-')
+	    abort ();
+
+	  sw = &switches[i + first];
+	  sw->part1 = &argbuf[i][1];
+	  sw->args = 0;
+	  sw->live_cond = SWITCH_OK;
+	  sw->validated = 0;
+	  sw->ordering = 0;
+	}
+    }
+}
+
 /* Process the sub-spec SPEC as a portion of a larger spec.
    This is like processing a whole spec except that we do
    not initialize at the beginning and we do not supply a
@@ -5917,6 +5963,12 @@ main (argc, argv)
 
   process_command (argc, argv);
 
+  /* Process DRIVER_SELF_SPECS, adding any new options to the end
+     of the command line.  */
+
+  for (i = 0; i < ARRAY_SIZE (driver_self_specs); i++)
+    do_self_spec (driver_self_specs[i]);
+
   /* Initialize the vector of specs to just the default.
      This means one element containing 0s, as a terminator.  */