Fix PR20425, multilib paths for -print-search-dirs

[Alan Modra <amodra at bigpond dot net dot au>]

This fixes a longstanding gcc/libtool complaint that the library search
path is wrong when using multilibs.  I've modified gcc -print-search-dirs
to print the library search path out twice if multilibs are in force,
first with the appropriate multilib suffixes, then without.  I also do
the same for LIBRARY_PATH_ENV.  The fact that this just extends the list
of directories printed should ameliorate concerns that changing
-print-search-paths like this will break existing uses.

Bootstrapped etc. powerpc64-linux and powerpc-linux.  OK for mainline?

	PR driver/20425
	* gcc.c (maybe_add_path): New function.
	(build_search_list): Add do_multi param.  Add search paths twice
	for multilibs, first with multilib suffix then without.
	(putenv_from_prefixes): Add do_multi param.
	(main): Adjust build_search_list and putenv_from_prefixes calls
	to give multilib paths for libraries.

Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c	(revision 108214)
+++ gcc/gcc.c	(working copy)
@@ -287,8 +287,9 @@ static char *load_specs (const char *);
 static void read_specs (const char *, int);
 static void set_spec (const char *, const char *);
 static struct compiler *lookup_compiler (const char *, size_t, const char *);
-static char *build_search_list (struct path_prefix *, const char *, int);
-static void putenv_from_prefixes (struct path_prefix *, const char *);
+static char *build_search_list (struct path_prefix *, const char *,
+				bool, bool);
+static void putenv_from_prefixes (struct path_prefix *, const char *, bool);
 static int access_check (const char *, int);
 static char *find_a_file (struct path_prefix *, const char *, int, int);
 static void add_prefix (struct path_prefix *, const char *, const char *,
@@ -2357,6 +2358,27 @@ clear_failure_queue (void)
   failure_delete_queue = 0;
 }
 
+/* Helper for build_search_list.  Adds concatentated str1 and str2 to
+   path currently being built.  */
+
+static bool
+maybe_add_path (struct obstack *ob, bool first_time, bool check_dir_p,
+		const char *str1, size_t str1_len,
+		const char *str2, size_t str2_len)
+{
+  if (check_dir_p && !is_directory (str1, str2 ? str2 : "", 0))
+    return first_time;
+
+  if (!first_time)
+    obstack_1grow (ob, PATH_SEPARATOR);
+
+  obstack_grow (ob, str1, str1_len);
+  if (str2_len)
+    obstack_grow (ob, str2, str2_len);
+
+  return false;
+}
+
 /* Build a list of search directories from PATHS.
    PREFIX is a string to prepend to the list.
    If CHECK_DIR_P is nonzero we ensure the directory exists.
@@ -2365,54 +2387,100 @@ clear_failure_queue (void)
 
 static char *
 build_search_list (struct path_prefix *paths, const char *prefix,
-		   int check_dir_p)
+		   bool check_dir_p, bool do_multi)
 {
-  int suffix_len = (machine_suffix) ? strlen (machine_suffix) : 0;
-  int just_suffix_len
-    = (just_machine_suffix) ? strlen (just_machine_suffix) : 0;
-  int first_time = TRUE;
-  struct prefix_list *pprefix;
+  bool first_time = true;
+  struct prefix_list *pl;
+  char *multi_dir = NULL;
+  char *multi_os_dir = NULL;
+  char *multi_suffix;
+  char *just_multi_suffix;
+
+  multi_suffix = machine_suffix;
+  just_multi_suffix = just_machine_suffix;
+  if (do_multi && multilib_dir)
+    {
+      multi_dir = concat (multilib_dir, dir_separator_str, NULL);
+      multi_os_dir = concat (multilib_os_dir, dir_separator_str, NULL);
+      if (multi_suffix)
+	multi_suffix = concat (multi_suffix, multi_dir, NULL);
+      if (just_multi_suffix)
+	just_multi_suffix = concat (just_multi_suffix, multi_dir, NULL);
+    }
 
   obstack_grow (&collect_obstack, prefix, strlen (prefix));
   obstack_1grow (&collect_obstack, '=');
 
-  for (pprefix = paths->plist; pprefix != 0; pprefix = pprefix->next)
+  /* Add paths twice, first with multilibs (if enabled), then without.  */
+  while (1)
     {
-      int len = strlen (pprefix->prefix);
-
-      if (machine_suffix
-	  && (! check_dir_p
-	      || is_directory (pprefix->prefix, machine_suffix, 0)))
-	{
-	  if (!first_time)
-	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);
-
-	  first_time = FALSE;
-	  obstack_grow (&collect_obstack, pprefix->prefix, len);
-	  obstack_grow (&collect_obstack, machine_suffix, suffix_len);
+      size_t multi_dir_len = 0;
+      size_t multi_os_dir_len = 0;
+      size_t suffix_len = 0;
+      size_t just_suffix_len = 0;
+
+      if (multi_dir)
+	multi_dir_len = strlen (multi_dir);
+      if (multi_os_dir)
+	multi_os_dir_len = strlen (multi_os_dir);
+      if (multi_suffix)
+	suffix_len = strlen (multi_suffix);
+      if (just_multi_suffix)
+	just_suffix_len = strlen (just_multi_suffix);
+
+      for (pl = paths->plist; pl != 0; pl = pl->next)
+	{
+	  int len = strlen (pl->prefix);
+	  char *path;
+
+	  if (multi_suffix)
+	    first_time
+	      = maybe_add_path (&collect_obstack, first_time, check_dir_p,
+				pl->prefix, len,
+				multi_suffix, suffix_len);
+
+	  if (just_multi_suffix
+	      && pl->require_machine_suffix == 2)
+	    first_time
+	      = maybe_add_path (&collect_obstack, first_time, check_dir_p,
+				pl->prefix, len,
+				just_multi_suffix, just_suffix_len);
+
+	  if (!pl->require_machine_suffix)
+	    {
+	      char *this_multi;
+	      size_t this_multi_len;
+	      if (pl->os_multilib)
+		{
+		  this_multi = multi_os_dir;
+		  this_multi_len = multi_os_dir_len;
+		}
+	      else
+		{
+		  this_multi = multi_dir;
+		  this_multi_len = multi_dir_len;
+		}
+	      first_time
+		= maybe_add_path (&collect_obstack, first_time, false,
+				  pl->prefix, len,
+				  this_multi, this_multi_len);
+	    }
 	}
-
-      if (just_machine_suffix
-	  && pprefix->require_machine_suffix == 2
-	  && (! check_dir_p
-	      || is_directory (pprefix->prefix, just_machine_suffix, 0)))
+      if (multi_dir == NULL)
+	break;
+      free (multi_dir);
+      multi_dir = NULL;
+      free (multi_os_dir);
+      multi_os_dir = NULL;
+      if (multi_suffix)
 	{
-	  if (! first_time)
-	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);
-
-	  first_time = FALSE;
-	  obstack_grow (&collect_obstack, pprefix->prefix, len);
-	  obstack_grow (&collect_obstack, just_machine_suffix,
-			just_suffix_len);
+	  free (multi_suffix);
+	  multi_suffix = machine_suffix;
 	}
-
-      if (! pprefix->require_machine_suffix)
+      if (just_multi_suffix)
 	{
-	  if (! first_time)
-	    obstack_1grow (&collect_obstack, PATH_SEPARATOR);
-
-	  first_time = FALSE;
-	  obstack_grow (&collect_obstack, pprefix->prefix, len);
+	  free (just_multi_suffix);
+	  just_multi_suffix = just_machine_suffix;
 	}
     }
 
@@ -2424,9 +2492,10 @@ build_search_list (struct path_prefix *p
    for collect.  */
 
 static void
-putenv_from_prefixes (struct path_prefix *paths, const char *env_var)
+putenv_from_prefixes (struct path_prefix *paths, const char *env_var,
+		      bool do_multi)
 {
-  putenv (build_search_list (paths, env_var, 1));
+  putenv (build_search_list (paths, env_var, true, do_multi));
 }
 
 /* Check whether NAME can be accessed in MODE.  This is like access,
@@ -6312,8 +6377,10 @@ main (int argc, char **argv)
   if (print_search_dirs)
     {
       printf (_("install: %s%s\n"), standard_exec_prefix, machine_suffix);
-      printf (_("programs: %s\n"), build_search_list (&exec_prefixes, "", 0));
-      printf (_("libraries: %s\n"), build_search_list (&startfile_prefixes, "", 0));
+      printf (_("programs: %s\n"),
+	      build_search_list (&exec_prefixes, "", false, false));
+      printf (_("libraries: %s\n"),
+	      build_search_list (&startfile_prefixes, "", false, true));
       return (0);
     }
 
@@ -6636,8 +6703,8 @@ main (int argc, char **argv)
 	}
       /* Rebuild the COMPILER_PATH and LIBRARY_PATH environment variables
 	 for collect.  */
-      putenv_from_prefixes (&exec_prefixes, "COMPILER_PATH");
-      putenv_from_prefixes (&startfile_prefixes, LIBRARY_PATH_ENV);
+      putenv_from_prefixes (&exec_prefixes, "COMPILER_PATH", false);
+      putenv_from_prefixes (&startfile_prefixes, LIBRARY_PATH_ENV, true);
 
       value = do_spec (link_command_spec);
       if (value < 0)

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre