Index: gcc/gcc/Makefile.in
===================================================================
--- gcc.orig/gcc/Makefile.in	2010-07-21 20:09:20.471160100 +0200
+++ gcc/gcc/Makefile.in	2010-07-21 21:19:04.099455400 +0200
@@ -366,6 +366,9 @@ USER_H = $(srcdir)/ginclude/float.h \
 	 $(srcdir)/ginclude/stdfix.h \
 	 $(EXTRA_HEADERS)
 
+USER_H_INC_NEXT_PRE = @user_headers_inc_next_pre_list@
+USER_H_INC_NEXT_POST = @user_headers_inc_next_post_list@
+
 UNWIND_H = $(srcdir)/unwind-generic.h
 
 # The GCC to use for compiling crt*.o.
@@ -4014,6 +4017,21 @@ stmp-int-hdrs: $(STMP_FIXINC) $(USER_H)
 	    chmod a+r include/$$realfile; \
 	  fi; \
 	done
+	for file in .. $(USER_H_INC_NEXT_PRE); do \
+	  if [ X$$file != X.. ]; then \
+            mv include/$$file include/x_$$file; \
+            echo "#include_next <$$file>" >include/$$file; \
+            cat include/x_$$file >>include/$$file; \
+            rm -f include/x_$$file; \
+	    chmod a+r include/$$file; \
+	  fi; \
+	done
+	for file in .. $(USER_H_INC_NEXT_POST); do \
+	  if [ X$$file != X.. ]; then \
+	    echo "#include_next <$$file>" >>include/$$file; \
+	    chmod a+r include/$$file; \
+	  fi; \
+	done
 	rm -f include/unwind.h
 	cp $(UNWIND_H) include/unwind.h
 	chmod a+r include/unwind.h
Index: gcc/gcc/config.gcc
===================================================================
--- gcc.orig/gcc/config.gcc	2010-07-21 20:09:20.376160100 +0200
+++ gcc/gcc/config.gcc	2010-07-21 20:33:43.484845200 +0200
@@ -101,6 +101,12 @@
 #  extra_headers	List of used header files from the directory
 #			config/${cpu_type}.
 #
+#  user_headers_inc_next_pre
+#			List of header file names of internal gcc header
+#			files, which should be prefixed by an include_next.
+#  user_headers_inc_next_post
+#			List of header file names of internal gcc header
+#			files, which should be postfixed by an include_next.
 #  use_gcc_tgmath	If set, add tgmath.h to the list of used header
 #			files.
 #
@@ -171,6 +177,8 @@
 out_file=
 tmake_file=
 extra_headers=
+user_headers_inc_next_pre=
+user_headers_inc_next_post=
 use_gcc_tgmath=yes
 use_gcc_stdint=none
 extra_passes=
@@ -1376,9 +1384,11 @@ i[34567]86-*-mingw* | x86_64-*-mingw*)
 		*)
 			;;
 	esac
+	user_headers_inc_next_post="${user_headers_inc_next_post} float.h"
 	# This makes the logic if mingw's or the w64 feature set has to be used
 	case ${target} in
 		*-w64-*)
+			user_headers_inc_next_pre="${user_headers_inc_next_pre} stddef.h stdarg.h"
 			tm_file="${tm_file} i386/mingw-w64.h"
 			if test x$enable_targets = xall; then
 				tm_defines="${tm_defines} TARGET_BI_ARCH=1"
Index: gcc/gcc/configure
===================================================================
--- gcc.orig/gcc/configure	2010-07-21 20:09:20.412160100 +0200
+++ gcc/gcc/configure	2010-07-21 20:36:04.899933600 +0200
@@ -646,6 +646,8 @@ extra_passes
 extra_parts
 extra_objs
 extra_headers_list
+user_headers_inc_next_post_list
+user_headers_inc_next_pre_list
 extra_gcc_objs
 TM_MULTILIB_EXCEPTIONS_CONFIG
 TM_MULTILIB_CONFIG
@@ -10263,6 +10265,12 @@ then tm_file=$cpu_type/$cpu_type.h; fi
 if test x"$extra_headers" = x
 then extra_headers=; fi
 
+if test x"$user_headers_inc_next_pre" = x
+then user_headers_inc_next_pre=; fi
+
+if test x"$user_headers_inc_next_post" = x
+then user_headers_inc_next_post=; fi
+
 if test x$md_file = x
 then md_file=$cpu_type/$cpu_type.md; fi
 
@@ -11003,6 +11011,16 @@ if test x"$use_gcc_tgmath" = xyes
 then extra_headers_list="${extra_headers_list} \$(srcdir)/ginclude/tgmath.h"
 fi
 
+# Expand user_headers_inc_next_pre to user_headers_inc_next_pre_list
+for file in ${user_headers_inc_next_pre} ; do
+  user_headers_inc_next_pre_list="${user_headers_inc_next_pre_list} ${file}"
+done
+
+# Expand user_headers_inc_next_post to user_headers_inc_next_post_list
+for file in ${user_headers_inc_next_post} ; do
+  user_headers_inc_next_post_list="${user_headers_inc_next_post_list} ${file}"
+done
+
 # Define collect2 in Makefile.
 case $host_can_use_collect2 in
   no) collect2= ;;
@@ -17107,7 +17125,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17110 "configure"
+#line 17128 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -17213,7 +17231,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17216 "configure"
+#line 17234 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -25394,6 +25412,8 @@ fi
 
 
 
+
+
 
 
 
Index: gcc/gcc/configure.ac
===================================================================
--- gcc.orig/gcc/configure.ac	2010-07-21 20:09:20.413160100 +0200
+++ gcc/gcc/configure.ac	2010-07-21 20:29:56.109840100 +0200
@@ -1235,6 +1235,12 @@ then tm_file=$cpu_type/$cpu_type.h; fi
 if test x"$extra_headers" = x
 then extra_headers=; fi
 
+if test x"$user_headers_inc_next_pre" = x
+then user_headers_inc_next_pre=; fi
+
+if test x"$user_headers_inc_next_post" = x
+then user_headers_inc_next_post=; fi
+
 if test x$md_file = x
 then md_file=$cpu_type/$cpu_type.md; fi
 
@@ -1823,6 +1829,16 @@ if test x"$use_gcc_tgmath" = xyes
 then extra_headers_list="${extra_headers_list} \$(srcdir)/ginclude/tgmath.h"
 fi
 
+# Expand user_headers_inc_next_pre to user_headers_inc_next_pre_list
+for file in ${user_headers_inc_next_pre} ; do
+  user_headers_inc_next_pre_list="${user_headers_inc_next_pre_list} ${file}"
+done
+
+# Expand user_headers_inc_next_post to user_headers_inc_next_post_list
+for file in ${user_headers_inc_next_post} ; do
+  user_headers_inc_next_post_list="${user_headers_inc_next_post_list} ${file}"
+done
+
 # Define collect2 in Makefile.
 case $host_can_use_collect2 in
   no) collect2= ;;
@@ -4499,6 +4515,8 @@ AC_SUBST(TM_ENDIAN_CONFIG)
 AC_SUBST(TM_MULTILIB_CONFIG)
 AC_SUBST(TM_MULTILIB_EXCEPTIONS_CONFIG)
 AC_SUBST(extra_gcc_objs)
+AC_SUBST(user_headers_inc_next_pre_list)
+AC_SUBST(user_headers_inc_next_post_list)
 AC_SUBST(extra_headers_list)
 AC_SUBST(extra_objs)
 AC_SUBST(extra_parts)