[PATCH] Relocated compiler should not look in $prefix.

[Carlos O'Donell <carlos at codesourcery dot com>]

A relocated compiler should not look in $prefix.

A relocated compiler should never search the configured prefix for
programs, libraries or start files. A relocated compiler searching for
files in the configured prefix is troublesome. The configured prefix may
contain a conflicting toolchain, or a slow network path.

The old behaviour of searching the conifgured prefix is not what users
expect from a relocated toolchain.

Consider 3 types of paths:

        1. Relocated paths.
        2. Configured prefix paths.
        3. Well known system paths.

The type 1 and type 3 paths are always added to our search lists. The
type 2 paths are only added if the compiler is installed at the
configured prefix.

This patch groups the 3 path types logically in gcc/gcc.c, and adds the
paths based on the wether the compiler is relocated or unrelocated.

The testing infrastructure also needs to be updated. Testing in the
object directory often uses libraries or start files from the configured
prefix. To enable testing from the object directory we export
GCC_EXEC_PREFIX with the value of the configured prefix. This gives the
old behaviour for the testsuite.

Comments?
OK for Stage1?

Tested without regression on i686-pc-linux-gnu (All languages),
arm-none-eabi, and arm-none-linux-gnueabi.

This is the first, of two, step to fixing pr17621.

Cheers,
Carlos.
-- 
Carlos O'Donell
CodeSourcery
carlos@codesourcery.com
(650) 331-3385 x716

2006-10-13  Carlos O'Donell  <carlos@codesourcery.com>
	    Mark Mitchell  <mark@codesourcery.com>
 
	* gcc.c: Organize search path variables into $prefix relative,
	and well-known native. Add comments.
	(add_sysrooted_prefix): Add comment.
	(process_command): If !gcc_exec_prefix add $prefix based paths.
	If *cross_compile == '0', add native well-known paths.
	Assert tooldir_base_prefix is always relative.
	(main): If print_search_dirs, and if gcc_exec_prefix is set,
	use this value for 'install:' path.
	* Makefile.in: Add GCC_EXEC_PREFIX to generated site.exp.
 
Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c	(revision 117699)
+++ gcc/gcc.c	(working copy)
@@ -1472,26 +1472,34 @@
 #define MD_STARTFILE_PREFIX_1 ""
 #endif
 
+/* These directories are locations set at configure-time based on the
+   --prefix option provided to configure.  Their initializers are
+   defined in Makefile.in.  These paths are not *directly* used when
+   gcc_exec_prefix is set because, in that case, we know where the
+   compiler has been installed, and use paths relative to that
+   location instead.  */
 static const char *const standard_exec_prefix = STANDARD_EXEC_PREFIX;
+static const char *const standard_libexec_prefix = STANDARD_LIBEXEC_PREFIX;
+static const char *const standard_bindir_prefix = STANDARD_BINDIR_PREFIX;
+static const char *const standard_startfile_prefix = STANDARD_STARTFILE_PREFIX;
+
+/* For native compilers, these are well-known paths containing
+   components that may be provided by the system.  For cross
+   compilers, these paths are not used.  */
 static const char *const standard_exec_prefix_1 = "/usr/libexec/gcc/";
 static const char *const standard_exec_prefix_2 = "/usr/lib/gcc/";
 static const char *md_exec_prefix = MD_EXEC_PREFIX;
-
 static const char *md_startfile_prefix = MD_STARTFILE_PREFIX;
 static const char *md_startfile_prefix_1 = MD_STARTFILE_PREFIX_1;
-static const char *const standard_startfile_prefix = STANDARD_STARTFILE_PREFIX;
-static const char *const standard_startfile_prefix_1
+static const char *const standard_startfile_prefix_1 
   = STANDARD_STARTFILE_PREFIX_1;
 static const char *const standard_startfile_prefix_2
   = STANDARD_STARTFILE_PREFIX_2;
 
+/* A relative path to be used in finding the location of tools
+   relative to the driver.  */
 static const char *const tooldir_base_prefix = TOOLDIR_BASE_PREFIX;
-static const char *tooldir_prefix;
 
-static const char *const standard_bindir_prefix = STANDARD_BINDIR_PREFIX;
-
-static const char *standard_libexec_prefix = STANDARD_LIBEXEC_PREFIX;
-
 /* Subdirectory to use for locating libraries.  Set by
    set_multilib_dir based on the compilation options.  */
 
@@ -2749,6 +2757,7 @@
 }
 
 /* Same as add_prefix, but prepending target_system_root to prefix.  */
+/* The target_system_root prefix has been relocated by gcc_exec_prefix.  */
 static void
 add_sysrooted_prefix (struct path_prefix *pprefix, const char *prefix,
 		      const char *component,
@@ -3278,6 +3287,7 @@
   int is_modify_target_name;
   unsigned int j;
 #endif
+  const char *tooldir_prefix;
 
   GET_ENVIRONMENT (gcc_exec_prefix, "GCC_EXEC_PREFIX");
 
@@ -3383,10 +3393,18 @@
       gcc_libexec_prefix = make_relative_prefix (tmp_prefix,
 						 standard_exec_prefix,
 						 standard_libexec_prefix);
+
+      /* The path is unrelocated, so fallback to the original setting.  */
+      if (!gcc_libexec_prefix)
+	gcc_libexec_prefix = standard_libexec_prefix;
+
       free (tmp_prefix);
     }
 #else
 #endif
+  /* From this point onward, gcc_exec_prefix is non-null if the toolchain
+     is relocated. The toolchain was either relocated using GCC_EXEC_PREFIX
+     or an automatically created GCC_EXEC_PREFIX from argv[0].  */
 
   if (gcc_exec_prefix)
     {
@@ -3933,63 +3951,51 @@
       use_pipes = 0;
     }
 
-  /* Set up the search paths before we go looking for config files.  */
+  /* Set up the search paths.  We add directories that we expect to
+     contain GNU Toolchain components before directories specified by
+     the machine description so that we will find GNU components (like
+     the GNU assembler) before those of the host system.  */ 
 
-  /* These come before the md prefixes so that we will find gcc's subcommands
-     (such as cpp) rather than those of the host system.  */
-  /* Use 2 as fourth arg meaning try just the machine as a suffix,
-     as well as trying the machine and the version.  */
+  /* If we don't know where the toolchain has been installed, use the
+     configured-in locations.  */
+  if (!gcc_exec_prefix)
+    {
 #ifndef OS2
-  add_prefix (&exec_prefixes, standard_libexec_prefix, "GCC",
-	      PREFIX_PRIORITY_LAST, 1, 0);
-  add_prefix (&exec_prefixes, standard_libexec_prefix, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 2, 0);
-  add_prefix (&exec_prefixes, standard_exec_prefix, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 2, 0);
-  add_prefix (&exec_prefixes, standard_exec_prefix_1, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 2, 0);
-  add_prefix (&exec_prefixes, standard_exec_prefix_2, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 2, 0);
+      add_prefix (&exec_prefixes, standard_libexec_prefix, "GCC",
+		  PREFIX_PRIORITY_LAST, 1, 0);
+      add_prefix (&exec_prefixes, standard_libexec_prefix, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 2, 0);
+      add_prefix (&exec_prefixes, standard_exec_prefix, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 2, 0);
 #endif
+      add_prefix (&startfile_prefixes, standard_exec_prefix, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 1, 0);
+    }
 
-  add_prefix (&startfile_prefixes, standard_exec_prefix, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 1, 0);
-  add_prefix (&startfile_prefixes, standard_exec_prefix_2, "BINUTILS",
-	      PREFIX_PRIORITY_LAST, 1, 0);
+  /* If not cross-compiling, search well-known system locations.  */
+  if (*cross_compile == '0')
+    {
+#ifndef OS2
+      add_prefix (&exec_prefixes, standard_exec_prefix_1, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 2, 0);
+      add_prefix (&exec_prefixes, standard_exec_prefix_2, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 2, 0);
+#endif
+      add_prefix (&startfile_prefixes, standard_exec_prefix_2, "BINUTILS",
+		  PREFIX_PRIORITY_LAST, 1, 0);
+    }
 
+  gcc_assert (!IS_ABSOLUTE_PATH (tooldir_base_prefix));
   tooldir_prefix = concat (tooldir_base_prefix, spec_machine,
 			   dir_separator_str, NULL);
 
-  /* If tooldir is relative, base it on exec_prefixes.  A relative
-     tooldir lets us move the installed tree as a unit.
+  /* Look for tools relative to the location from which the driver is
+     running, or, if that is not available, the configured prefix.  */
+  tooldir_prefix
+    = concat (gcc_exec_prefix ? gcc_exec_prefix : standard_exec_prefix,
+	      spec_machine, dir_separator_str,
+	      spec_version, dir_separator_str, tooldir_prefix, NULL);
 
-     If GCC_EXEC_PREFIX is defined, then we want to add two relative
-     directories, so that we can search both the user specified directory
-     and the standard place.  */
-
-  if (!IS_ABSOLUTE_PATH (tooldir_prefix))
-    {
-      if (gcc_exec_prefix)
-	{
-	  char *gcc_exec_tooldir_prefix
-	    = concat (gcc_exec_prefix, spec_machine, dir_separator_str,
-		      spec_version, dir_separator_str, tooldir_prefix, NULL);
-
-	  add_prefix (&exec_prefixes,
-		      concat (gcc_exec_tooldir_prefix, "bin",
-			      dir_separator_str, NULL),
-		      NULL, PREFIX_PRIORITY_LAST, 0, 0);
-	  add_prefix (&startfile_prefixes,
-		      concat (gcc_exec_tooldir_prefix, "lib",
-			      dir_separator_str, NULL),
-		      NULL, PREFIX_PRIORITY_LAST, 0, 1);
-	}
-
-      tooldir_prefix = concat (standard_exec_prefix, spec_machine,
-			       dir_separator_str, spec_version,
-			       dir_separator_str, tooldir_prefix, NULL);
-    }
-
   add_prefix (&exec_prefixes,
 	      concat (tooldir_prefix, "bin", dir_separator_str, NULL),
 	      "BINUTILS", PREFIX_PRIORITY_LAST, 0, 0);
@@ -6311,18 +6317,16 @@
 			      PREFIX_PRIORITY_LAST, 0, 1);
       else if (*cross_compile == '0')
 	{
-	  if (gcc_exec_prefix)
-	    add_prefix (&startfile_prefixes,
-			concat (gcc_exec_prefix, machine_suffix,
-				standard_startfile_prefix, NULL),
-			NULL, PREFIX_PRIORITY_LAST, 0, 1);
 	  add_prefix (&startfile_prefixes,
-		      concat (standard_exec_prefix,
-			      machine_suffix,
+		      concat (gcc_exec_prefix 
+			      ? gcc_exec_prefix : standard_exec_prefix, 
+			      machine_suffix, 
 			      standard_startfile_prefix, NULL),
 		      NULL, PREFIX_PRIORITY_LAST, 0, 1);
 	}
 
+      /* Sysrooted prefixes are relocated because target_system_root is
+	 also relocated by gcc_exec_prefix.  */
       if (*standard_startfile_prefix_1)
  	add_sysrooted_prefix (&startfile_prefixes,
 			      standard_startfile_prefix_1, "BINUTILS",
@@ -6366,7 +6370,9 @@
 
   if (print_search_dirs)
     {
-      printf (_("install: %s%s\n"), standard_exec_prefix, machine_suffix);
+      printf (_("install: %s%s\n"),
+	      gcc_exec_prefix ? gcc_exec_prefix : standard_exec_prefix,
+	      gcc_exec_prefix ? "" : machine_suffix);
       printf (_("programs: %s\n"),
 	      build_search_list (&exec_prefixes, "", false, false));
       printf (_("libraries: %s\n"),
Index: gcc/Makefile.in
===================================================================
--- gcc/Makefile.in	(revision 117699)
+++ gcc/Makefile.in	(working copy)
@@ -3984,6 +3984,7 @@
 	@echo "set HOSTCFLAGS \"$(CFLAGS)\"" >> ./tmp0
 	@echo "set TESTING_IN_BUILD_TREE 1" >> ./tmp0
 	@echo "set HAVE_LIBSTDCXX_V3 1" >> ./tmp0
+	@echo "set GCC_EXEC_PREFIX \"$(libdir)/gcc/\"" >> ./tmp0
 # If newlib has been configured, we need to pass -B to gcc so it can find
 # newlib's crt0.o if it exists.  This will cause a "path prefix not used"
 # message if it doesn't, but the testsuite is supposed to ignore the message -
===================================================================

2006-10-13  Carlos O'Donell  <carlos@codesourcery.com>

	* lib/c-torture.exp: Use target-libpath.exp.
	* lib/target-libpath.exp (set_ld_library_path_env_vars): If present,
	set GCC_EXEC_PREFIX env var from global variable of same name.

Index: gcc/testsuite/lib/c-torture.exp
===================================================================
--- gcc/testsuite/lib/c-torture.exp	(revision 117699)
+++ gcc/testsuite/lib/c-torture.exp	(working copy)
@@ -17,6 +17,7 @@
 # This file was written by Rob Savoye. (rob@cygnus.com)
 
 load_lib file-format.exp
+load_lib target-libpath.exp
 
 # The default option list can be overridden by
 # TORTURE_OPTIONS="{ { list1 } ... { listN } }"
@@ -40,7 +41,20 @@
 	{ -Os } ]
 }
 
+global GCC_UNDER_TEST
+if ![info exists GCC_UNDER_TEST] {
+    set GCC_UNDER_TEST "[find_gcc]"
+}
 
+global orig_environment_saved
+
+# This file may be sourced, so don't override environment settings
+# that have been previously setup.
+if { $orig_environment_saved == 0 } {
+    append ld_library_path [gcc-set-multilib-library-path $GCC_UNDER_TEST]
+    set_ld_library_path_env_vars
+}
+
 # Split TORTURE_OPTIONS into two choices: one for testcases with loops and
 # one for testcases without loops.
 
Index: gcc/testsuite/lib/target-libpath.exp
===================================================================
--- gcc/testsuite/lib/target-libpath.exp	(revision 117699)
+++ gcc/testsuite/lib/target-libpath.exp	(working copy)
@@ -50,7 +50,13 @@
   global orig_ld_library_path_32
   global orig_ld_library_path_64
   global orig_dyld_library_path
+  global GCC_EXEC_PREFIX
 
+  # Set the relocated compiler prefix, but only if the user hasn't specified one.
+  if { [info exists GCC_EXEC_PREFIX] && ![info exists env(GCC_EXEC_PREFIX)] } {
+    setenv GCC_EXEC_PREFIX "$GCC_EXEC_PREFIX"
+  }
+
   # Setting the ld library path causes trouble when testing cross-compilers.
   if { [is_remote target] } {
     return