PR libstdc++/25524

	* cppdefault.h (struct default_include): Add multilib flag.
	* cppdefault.c (cpp_include_defaults): Set it.
	* c.opt (-imultilib): New option.
	* c-opts.c (imultilib): New.
	(c_common_handle_option): Handle -imultilib.
	(c_common_post_options): Likewise.
	* c-incpath.c (add_standard_paths, register_include_chains):
	Likewise.
	* c-incpath.h (register_include_chains): Add extra parameter.
	* gcc.c (do_spec_1): Generate -imultilib option.
	(The Specs Language): Update %I description.
	(process_command): Update copyright notice.
	* doc/cppopts.texi (-imultilib): Document.
	* doc/invoke.texi (-imultilib): Include in option summary.
	(%I): Update specs documentation.

libstdc++-v3:
	* include/Makefile.am: Install host-specific headers in multilib
	subdirectory.
	* include/Makefile.in: Regenerate.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@110037 138bc75d-0d04-0410-961f-82ee72b054a4

13 files changed, 116 insertions, 47 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 35d72cf28dd..c41ef43e98c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,22 @@
+2006-01-20  Joseph S. Myers  <joseph@codesourcery.com>
+
+	PR libstdc++/25524
+	* cppdefault.h (struct default_include): Add multilib flag.
+	* cppdefault.c (cpp_include_defaults): Set it.
+	* c.opt (-imultilib): New option.
+	* c-opts.c (imultilib): New.
+	(c_common_handle_option): Handle -imultilib.
+	(c_common_post_options): Likewise.
+	* c-incpath.c (add_standard_paths, register_include_chains):
+	Likewise.
+	* c-incpath.h (register_include_chains): Add extra parameter.
+	* gcc.c (do_spec_1): Generate -imultilib option.
+	(The Specs Language): Update %I description.
+	(process_command): Update copyright notice.
+	* doc/cppopts.texi (-imultilib): Document.
+	* doc/invoke.texi (-imultilib): Include in option summary.
+	(%I): Update specs documentation.
+
 2006-01-20  Zdenek Dvorak <dvorakz@suse.cz>
 
 	* loop-iv.c (iv_analysis_loop_init): Use df in more conservative way.
diff --git a/gcc/c-incpath.c b/gcc/c-incpath.c
index 38611068a79..fc1e3149bb2 100644
--- a/gcc/c-incpath.c
+++ b/gcc/c-incpath.c
@@ -1,6 +1,7 @@
 /* Set up combined include path chain for the preprocessor.
    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+   Free Software Foundation, Inc.
 
    Broken out of cppinit.c and cppfiles.c and rewritten Mar 2003.
 
@@ -45,8 +46,10 @@ Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 # define INO_T_COPY(DEST, SRC) (DEST) = (SRC)
 #endif
 
+static const char dir_separator_str[] = { DIR_SEPARATOR, 0 };
+
 static void add_env_var_paths (const char *, int);
-static void add_standard_paths (const char *, const char *, int);
+static void add_standard_paths (const char *, const char *, const char *, int);
 static void free_path (struct cpp_dir *, int);
 static void merge_include_chains (cpp_reader *, int);
 static struct cpp_dir *remove_duplicates (cpp_reader *, struct cpp_dir *,
@@ -120,7 +123,8 @@ add_env_var_paths (const char *env_var, int chain)
 
 /* Append the standard include chain defined in cppdefault.c.  */
 static void
-add_standard_paths (const char *sysroot, const char *iprefix, int cxx_stdinc)
+add_standard_paths (const char *sysroot, const char *iprefix,
+		    const char *imultilib, int cxx_stdinc)
 {
   const struct default_include *p;
   size_t len;
@@ -142,6 +146,8 @@ add_standard_paths (const char *sysroot, const char *iprefix, int cxx_stdinc)
 	      if (!strncmp (p->fname, cpp_GCC_INCLUDE_DIR, len))
 		{
 		  char *str = concat (iprefix, p->fname + len, NULL);
+		  if (p->multilib && imultilib)
+		    str = concat (str, dir_separator_str, imultilib, NULL);
 		  add_path (str, SYSTEM, p->cxx_aware, false);
 		}
 	    }
@@ -160,6 +166,9 @@ add_standard_paths (const char *sysroot, const char *iprefix, int cxx_stdinc)
 	  else
 	    str = update_path (p->fname, p->component);
 
+	  if (p->multilib && imultilib)
+	    str = concat (str, dir_separator_str, imultilib, NULL);
+
 	  add_path (str, SYSTEM, p->cxx_aware, false);
 	}
     }
@@ -357,8 +366,8 @@ add_path (char *path, int chain, int cxx_aware, bool user_supplied_p)
    removal, and registration with cpplib.  */
 void
 register_include_chains (cpp_reader *pfile, const char *sysroot,
-			 const char *iprefix, int stdinc, int cxx_stdinc,
-			 int verbose)
+			 const char *iprefix, const char *imultilib,
+			 int stdinc, int cxx_stdinc, int verbose)
 {
   static const char *const lang_env_vars[] =
     { "C_INCLUDE_PATH", "CPLUS_INCLUDE_PATH",
@@ -380,7 +389,7 @@ register_include_chains (cpp_reader *pfile, const char *sysroot,
 
   /* Finally chain on the standard directories.  */
   if (stdinc)
-    add_standard_paths (sysroot, iprefix, cxx_stdinc);
+    add_standard_paths (sysroot, iprefix, imultilib, cxx_stdinc);
 
   target_c_incpath.extra_includes (sysroot, iprefix, stdinc);
 
diff --git a/gcc/c-incpath.h b/gcc/c-incpath.h
index c309844cf0a..3f268b79d57 100644
--- a/gcc/c-incpath.h
+++ b/gcc/c-incpath.h
@@ -1,5 +1,5 @@
 /* Set up combined include path for the preprocessor.
-   Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 
 This program is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
@@ -18,7 +18,8 @@ Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 extern void split_quote_chain (void);
 extern void add_path (char *, int, int, bool);
 extern void register_include_chains (cpp_reader *, const char *,
-				     const char *, int, int, int);
+				     const char *, const char *,
+				     int, int, int);
 extern void add_cpp_dir_path (struct cpp_dir *, int);
 
 struct target_c_incpath_s {
diff --git a/gcc/c-opts.c b/gcc/c-opts.c
index 9968c9b187b..f508e4e0481 100644
--- a/gcc/c-opts.c
+++ b/gcc/c-opts.c
@@ -1,5 +1,5 @@
 /* C/ObjC/C++ command line option handling.
-   Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
    Contributed by Neil Booth.
 
 This file is part of GCC.
@@ -79,6 +79,9 @@ static const char *deps_file;
 /* The prefix given by -iprefix, if any.  */
 static const char *iprefix;
 
+/* The multilib directory given by -imultilib, if any.  */
+static const char *imultilib;
+
 /* The system root, if any.  Overridden by -isysroot.  */
 static const char *sysroot = TARGET_SYSTEM_ROOT;
 
@@ -815,6 +818,10 @@ c_common_handle_option (size_t scode, const char *arg, int value)
       defer_opt (code, arg);
       break;
 
+    case OPT_imultilib:
+      imultilib = arg;
+      break;
+
     case OPT_iprefix:
       iprefix = arg;
       break;
@@ -967,7 +974,7 @@ c_common_post_options (const char **pfilename)
 
   sanitize_cpp_opts ();
 
-  register_include_chains (parse_in, sysroot, iprefix,
+  register_include_chains (parse_in, sysroot, iprefix, imultilib,
 			   std_inc, std_cxx_inc && c_dialect_cxx (), verbose);
 
   flag_inline_trees = 1;
diff --git a/gcc/c.opt b/gcc/c.opt
index 9d11ca6f052..a37f4982b73 100644
--- a/gcc/c.opt
+++ b/gcc/c.opt
@@ -1,5 +1,5 @@
 ; Options for the C, ObjC, C++ and ObjC++ front ends.
-; Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+; Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 ;
 ; This file is part of GCC.
 ;
@@ -757,6 +757,10 @@ imacros
 C ObjC C++ ObjC++ Joined Separate
 -imacros <file>	Accept definition of macros in <file>
 
+imultilib
+C ObjC C++ ObjC++ Joined Separate
+-imultilib <dir> Set <dir> to be the multilib include subdirectory
+
 include
 C ObjC C++ ObjC++ Joined Separate
 -include <file>	Include the contents of <file> before other files
diff --git a/gcc/cppdefault.c b/gcc/cppdefault.c
index bcb8fe20715..d040558b54c 100644
--- a/gcc/cppdefault.c
+++ b/gcc/cppdefault.c
@@ -1,6 +1,6 @@
 /* CPP Library.
    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2003, 2004 Free Software Foundation, Inc.
+   1999, 2000, 2003, 2004, 2006 Free Software Foundation, Inc.
    Contributed by Per Bothner, 1994-95.
    Based on CCCP program by Paul Rubin, June 1986
    Adapted to ANSI C, Richard Stallman, Jan 1987
@@ -48,44 +48,44 @@ const struct default_include cpp_include_defaults[]
 = {
 #ifdef GPLUSPLUS_INCLUDE_DIR
     /* Pick up GNU C++ generic include files.  */
-    { GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1, 0 },
+    { GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1, 0, 0 },
 #endif
 #ifdef GPLUSPLUS_TOOL_INCLUDE_DIR
     /* Pick up GNU C++ target-dependent include files.  */
-    { GPLUSPLUS_TOOL_INCLUDE_DIR, "G++", 1, 1, 0 },
+    { GPLUSPLUS_TOOL_INCLUDE_DIR, "G++", 1, 1, 0, 1 },
 #endif
 #ifdef GPLUSPLUS_BACKWARD_INCLUDE_DIR
     /* Pick up GNU C++ backward and deprecated include files.  */
-    { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, 0 },
+    { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, 0, 0 },
 #endif
 #ifdef LOCAL_INCLUDE_DIR
     /* /usr/local/include comes before the fixincluded header files.  */
-    { LOCAL_INCLUDE_DIR, 0, 0, 1, 1 },
+    { LOCAL_INCLUDE_DIR, 0, 0, 1, 1, 0 },
 #endif
 #ifdef PREFIX_INCLUDE_DIR
-    { PREFIX_INCLUDE_DIR, 0, 0, 1, 0 },
+    { PREFIX_INCLUDE_DIR, 0, 0, 1, 0, 0 },
 #endif
 #ifdef GCC_INCLUDE_DIR
     /* This is the dir for fixincludes and for gcc's private headers.  */
-    { GCC_INCLUDE_DIR, "GCC", 0, 0, 0 },
+    { GCC_INCLUDE_DIR, "GCC", 0, 0, 0, 0 },
 #endif
 #ifdef CROSS_INCLUDE_DIR
     /* One place the target system's headers might be.  */
-    { CROSS_INCLUDE_DIR, "GCC", 0, 0, 0 },
+    { CROSS_INCLUDE_DIR, "GCC", 0, 0, 0, 0 },
 #endif
 #ifdef TOOL_INCLUDE_DIR
     /* Another place the target system's headers might be.  */
-    { TOOL_INCLUDE_DIR, "BINUTILS", 0, 1, 0 },
+    { TOOL_INCLUDE_DIR, "BINUTILS", 0, 1, 0, 0 },
 #endif
 #ifdef SYSTEM_INCLUDE_DIR
     /* Some systems have an extra dir of include files.  */
-    { SYSTEM_INCLUDE_DIR, 0, 0, 0, 1 },
+    { SYSTEM_INCLUDE_DIR, 0, 0, 0, 1, 0 },
 #endif
 #ifdef STANDARD_INCLUDE_DIR
     /* /usr/include comes dead last.  */
-    { STANDARD_INCLUDE_DIR, STANDARD_INCLUDE_COMPONENT, 0, 0, 1 },
+    { STANDARD_INCLUDE_DIR, STANDARD_INCLUDE_COMPONENT, 0, 0, 1, 0 },
 #endif
-    { 0, 0, 0, 0, 0 }
+    { 0, 0, 0, 0, 0, 0 }
   };
 #endif /* no INCLUDE_DEFAULTS */
 
diff --git a/gcc/cppdefault.h b/gcc/cppdefault.h
index f5b38884de6..a3a24169554 100644
--- a/gcc/cppdefault.h
+++ b/gcc/cppdefault.h
@@ -1,6 +1,6 @@
 /* CPP Library.
    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2003, 2004 Free Software Foundation, Inc.
+   1999, 2000, 2003, 2004, 2006 Free Software Foundation, Inc.
    Contributed by Per Bothner, 1994-95.
    Based on CCCP program by Paul Rubin, June 1986
    Adapted to ANSI C, Richard Stallman, Jan 1987
@@ -43,6 +43,9 @@ struct default_include
 				   C++.  */
   const char add_sysroot;	/* FNAME should be prefixed by
 				   cpp_SYSROOT.  */
+  const char multilib;		/* FNAME should have the multilib path
+				   specified with -imultilib
+				   appended.  */
 };
 
 extern const struct default_include cpp_include_defaults[];
diff --git a/gcc/doc/cppopts.texi b/gcc/doc/cppopts.texi
index adf77e1802a..06ca0b90880 100644
--- a/gcc/doc/cppopts.texi
+++ b/gcc/doc/cppopts.texi
@@ -1,4 +1,4 @@
-@c Copyright (c) 1999, 2000, 2001, 2002, 2003, 2004, 2005
+@c Copyright (c) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
 @c Free Software Foundation, Inc.
 @c This is part of the CPP and GCC manuals.
 @c For copying conditions, see the file gcc.texi.
@@ -483,6 +483,11 @@ would; @option{-iwithprefix} puts it where @option{-idirafter} would.
 This option is like the @option{--sysroot} option, but applies only to
 header files.  See the @option{--sysroot} option for more information.
 
+@item -imultilib @var{dir}
+@opindex imultilib
+Use @var{dir} as a subdirectory of the directory containing
+target-specific C++ headers.
+
 @item -isystem @var{dir}
 @opindex isystem
 Search @var{dir} for header files, after all directories specified by
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 3a19fb9c36b..1e5a2167077 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -9,8 +9,8 @@
 @c man end
 
 @c man begin COPYRIGHT
-Copyright @copyright{} 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
-1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+Copyright @copyright{} 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.2 or
@@ -358,7 +358,7 @@ Objective-C and Objective-C++ Dialects}.
 -include @var{file}  -imacros @var{file} @gol
 -iprefix @var{file}  -iwithprefix @var{dir} @gol
 -iwithprefixbefore @var{dir}  -isystem @var{dir} @gol
--isysroot @var{dir} @gol
+-imultilib @var{dir} -isysroot @var{dir} @gol
 -M  -MM  -MF  -MG  -MP  -MQ  -MT  -nostdinc  @gol
 -P  -fworking-directory  -remap @gol
 -trigraphs  -undef  -U@var{macro}  -Wp,@var{option} @gol
@@ -6862,9 +6862,9 @@ C@.
 
 @item %I
 Substitute any of @option{-iprefix} (made from @env{GCC_EXEC_PREFIX}),
-@option{-isysroot} (made from @env{TARGET_SYSTEM_ROOT}), and
+@option{-isysroot} (made from @env{TARGET_SYSTEM_ROOT}),
 @option{-isystem} (made from @env{COMPILER_PATH} and @option{-B} options)
-as necessary.
+and @option{-imultilib} as necessary.
 
 @item %s
 Current argument is the name of a library or startup file of some sort.
diff --git a/gcc/gcc.c b/gcc/gcc.c
index bff3ae8de4c..0bd34eea40c 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -1,6 +1,6 @@
 /* Compiler driver program that can handle many languages.
    Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation,
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation,
    Inc.
 
 This file is part of GCC.
@@ -441,8 +441,8 @@ or with constant text in a single argument.
 	SUFFIX characters following %O as they would following, for
 	example, `.o'.
  %I	Substitute any of -iprefix (made from GCC_EXEC_PREFIX), -isysroot
-	(made from TARGET_SYSTEM_ROOT), and -isystem (made from COMPILER_PATH
-	and -B options) as necessary.
+	(made from TARGET_SYSTEM_ROOT), -isystem (made from COMPILER_PATH
+	and -B options) and -imultilib as necessary.
  %s     current argument is the name of a library or startup file of some sort.
         Search for that file in a standard list of directories
 	and substitute the full name found.
@@ -3535,7 +3535,7 @@ process_command (int argc, const char **argv)
 	{
 	  /* translate_options () has turned --version into -fversion.  */
 	  printf (_("%s (GCC) %s\n"), programname, version_string);
-	  printf ("Copyright %s 2005 Free Software Foundation, Inc.\n",
+	  printf ("Copyright %s 2006 Free Software Foundation, Inc.\n",
 		  _("(C)"));
 	  fputs (_("This is free software; see the source for copying conditions.  There is NO\n\
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\n"),
@@ -4947,6 +4947,15 @@ do_spec_1 (const char *spec, int inswitch, const char *soft_matched_part)
 	    {
 	      struct spec_path_info info;
 
+	      if (multilib_dir)
+		{
+		  do_spec_1 ("-imultilib", 1, NULL);
+		  /* Make this a separate argument.  */
+		  do_spec_1 (" ", 0, NULL);
+		  do_spec_1 (multilib_dir, 1, NULL);
+		  do_spec_1 (" ", 0, NULL);
+		}
+
 	      if (gcc_exec_prefix)
 		{
 		  do_spec_1 ("-iprefix", 1, NULL);
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index d699d6f16d7..b88a3b6f7c9 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2006-01-20  Joseph S. Myers  <joseph@codesourcery.com>
+
+	PR libstdc++/25524
+	* include/Makefile.am: Install host-specific headers in multilib
+	subdirectory.
+	* include/Makefile.in: Regenerate.
+
 2006-01-19  Paolo Carlini  <pcarlini@suse.de>
 
 	Implement list::splice (and merge) bits of N1599
diff --git a/libstdc++-v3/include/Makefile.am b/libstdc++-v3/include/Makefile.am
index faa23495f14..046207501e5 100644
--- a/libstdc++-v3/include/Makefile.am
+++ b/libstdc++-v3/include/Makefile.am
@@ -1,6 +1,7 @@
 ## Makefile for the include subdirectory of the GNU C++ Standard library.
 ##
-## Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+## Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
+## Free Software Foundation, Inc.
 ##
 ## This file is part of the libstdc++ version 3 distribution.
 ## Process this file with automake to produce Makefile.in.
@@ -614,6 +615,7 @@ endif
 
 host_srcdir = ${glibcxx_srcdir}/$(OS_INC_SRCDIR)
 host_builddir = ./${host_alias}/bits
+host_installdir = ${gxx_include_dir}/${host_alias}$(MULTISUBDIR)/bits
 host_headers = \
 	${host_srcdir}/ctype_base.h \
 	${host_srcdir}/ctype_inline.h \
@@ -648,6 +650,7 @@ thread_host_headers = \
 
 pch_input = ${host_builddir}/stdc++.h
 pch_output_builddir = ${host_builddir}/stdc++.h.gch
+pch_output_installdir = ${host_installdir}/stdc++.h.gch
 pch_source = ${glibcxx_srcdir}/include/stdc++.h
 PCHFLAGS=-Winvalid-pch -Wno-deprecated -x c++-header $(CXXFLAGS)
 if GLIBCXX_BUILD_PCH
@@ -920,9 +923,9 @@ endif
 # are copied here.
 install-freestanding-headers:
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${host_builddir}
+	$(mkinstalldirs) $(DESTDIR)${host_installdir}
 	for file in ${host_srcdir}/os_defines.h ${host_builddir}/c++config.h; do \
-	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${host_builddir}; done
+	  $(INSTALL_DATA) $${file} $(DESTDIR)${host_installdir}; done
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${std_builddir}
 	$(INSTALL_DATA) ${std_builddir}/limits $(DESTDIR)${gxx_include_dir}/${std_builddir}
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${c_base_builddir}
@@ -982,15 +985,15 @@ install-headers:
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${debug_builddir}
 	for file in ${debug_headers}; do \
 	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${debug_builddir}; done
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${host_builddir}
+	$(mkinstalldirs) $(DESTDIR)${host_installdir}
 	for file in ${host_headers} ${host_headers_extra} \
 	 ${thread_host_headers}; do \
-	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${host_builddir}; done
+	  $(INSTALL_DATA) $${file} $(DESTDIR)${host_installdir}; done
 
 install-pch:
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${pch_output_builddir}
+	$(mkinstalldirs) $(DESTDIR)${pch_output_installdir}
 	for file in ${pch_output_builddir}/*; do \
-	  $(INSTALL_DATA) $$file $(DESTDIR)${gxx_include_dir}/${pch_output_builddir}; done
+	  $(INSTALL_DATA) $$file $(DESTDIR)${pch_output_installdir}; done
 
 # By adding these files here, automake will remove them for 'make clean'
 CLEANFILES = ${pch_input} ${pch_output_builddir}/*
diff --git a/libstdc++-v3/include/Makefile.in b/libstdc++-v3/include/Makefile.in
index 2425898ff29..49a0f48ab65 100644
--- a/libstdc++-v3/include/Makefile.in
+++ b/libstdc++-v3/include/Makefile.in
@@ -828,6 +828,7 @@ debug_headers = \
 @GLIBCXX_C_HEADERS_COMPATIBILITY_TRUE@c_compatibility_headers_extra = ${c_compatibility_headers}
 host_srcdir = ${glibcxx_srcdir}/$(OS_INC_SRCDIR)
 host_builddir = ./${host_alias}/bits
+host_installdir = ${gxx_include_dir}/${host_alias}$(MULTISUBDIR)/bits
 host_headers = \
 	${host_srcdir}/ctype_base.h \
 	${host_srcdir}/ctype_inline.h \
@@ -864,6 +865,7 @@ thread_host_headers = \
 
 pch_input = ${host_builddir}/stdc++.h
 pch_output_builddir = ${host_builddir}/stdc++.h.gch
+pch_output_installdir = ${host_installdir}/stdc++.h.gch
 pch_source = ${glibcxx_srcdir}/include/stdc++.h
 PCHFLAGS = -Winvalid-pch -Wno-deprecated -x c++-header $(CXXFLAGS)
 @GLIBCXX_BUILD_PCH_FALSE@pch_build = 
@@ -1293,9 +1295,9 @@ ${pch_input}: ${allstamped} ${host_builddir}/c++config.h ${pch_source}
 # are copied here.
 install-freestanding-headers:
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${host_builddir}
+	$(mkinstalldirs) $(DESTDIR)${host_installdir}
 	for file in ${host_srcdir}/os_defines.h ${host_builddir}/c++config.h; do \
-	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${host_builddir}; done
+	  $(INSTALL_DATA) $${file} $(DESTDIR)${host_installdir}; done
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${std_builddir}
 	$(INSTALL_DATA) ${std_builddir}/limits $(DESTDIR)${gxx_include_dir}/${std_builddir}
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${c_base_builddir}
@@ -1355,15 +1357,15 @@ install-headers:
 	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${debug_builddir}
 	for file in ${debug_headers}; do \
 	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${debug_builddir}; done
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${host_builddir}
+	$(mkinstalldirs) $(DESTDIR)${host_installdir}
 	for file in ${host_headers} ${host_headers_extra} \
 	 ${thread_host_headers}; do \
-	  $(INSTALL_DATA) $${file} $(DESTDIR)${gxx_include_dir}/${host_builddir}; done
+	  $(INSTALL_DATA) $${file} $(DESTDIR)${host_installdir}; done
 
 install-pch:
-	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${pch_output_builddir}
+	$(mkinstalldirs) $(DESTDIR)${pch_output_installdir}
 	for file in ${pch_output_builddir}/*; do \
-	  $(INSTALL_DATA) $$file $(DESTDIR)${gxx_include_dir}/${pch_output_builddir}; done
+	  $(INSTALL_DATA) $$file $(DESTDIR)${pch_output_installdir}; done
 
 # Stop implicit '.o' make rules from ever stomping on extensionless
 # headers, in the improbable case where some foolish, crack-addled