Index: gcc-4.5/gcc/Makefile.in
===================================================================
--- gcc-4.5.orig/gcc/Makefile.in
+++ gcc-4.5/gcc/Makefile.in
@@ -656,7 +656,7 @@ LIBGCC2_INCLUDES =
 TARGET_LIBGCC2_CFLAGS =
 
 # Options to use when compiling crtbegin/end.
-CRTSTUFF_CFLAGS = -O2 $(GCC_CFLAGS) $(INCLUDES) $(MULTILIB_CFLAGS) -g0 \
+CRTSTUFF_CFLAGS = -O2 $(GCC_CFLAGS) $(TARGET_INCLUDES) $(MULTILIB_CFLAGS) -g0 \
   -finhibit-size-directive -fno-inline -fno-exceptions \
   -fno-zero-initialized-in-bss -fno-toplevel-reorder -fno-tree-vectorize \
   $(INHIBIT_LIBC_CFLAGS)
@@ -1038,10 +1038,14 @@ BUILD_ERRORS = build/errors.o
 # -I$(@D) and -I$(srcdir)/$(@D) cause the subdirectory of the file
 # currently being compiled, in both source trees, to be examined as well.
 # libintl.h will be found in ../intl if we are using the included libintl.
-INCLUDES = -I. -I$(@D) -I$(srcdir) -I$(srcdir)/$(@D) \
+#
+# TARGET_INCLUDES is added to avoid that GMPINC (which points to the host
+# include dir) is used for compiling libgcc.a
+TARGET_INCLUDES = -I. -I$(@D) -I$(srcdir) -I$(srcdir)/$(@D) \
 	   -I$(srcdir)/../include @INCINTL@ \
-	   $(CPPINC) $(GMPINC) $(DECNUMINC) \
+	   $(CPPINC) $(DECNUMINC) \
 	   $(PPLINC) $(CLOOGINC) $(LIBELFINC)
+INCLUDES = $(TARGET_INCLUDES) $(GMPINC)
 
 .c.o:
 	$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $< $(OUTPUT_OPTION)
