diff --git a/libbacktrace/ChangeLog b/libbacktrace/ChangeLog
index 15a94391a1e4e85531cb2b1aa6a5fe5d2e95d944..814a1c92b91f335943f633b44d35f85f494c6942 100644
--- a/libbacktrace/ChangeLog
+++ b/libbacktrace/ChangeLog
@@ -1,3 +1,10 @@
+2012-09-18  Ian Lance Taylor  <iant@google.com>
+
+	PR bootstrap/54623
+	* Makefile.am (AM_CPPFLAGS): Define.
+	(AM_CFLAGS): Remove -I options.
+	* Makefile.in: Rebuild.
+
 2012-09-18  Ian Lance Taylor  <iant@google.com>
 
 	* posix.c (O_BINARY): Define if not defined.
diff --git a/libbacktrace/Makefile.am b/libbacktrace/Makefile.am
index 0cbed3b834563d458c94b74f084e8de6f317ab85..2492ca2cc2780d595eb975ad4deb7a457986a0cb 100644
--- a/libbacktrace/Makefile.am
+++ b/libbacktrace/Makefile.am
@@ -31,7 +31,10 @@
 
 ACLOCAL_AMFLAGS = -I .. -I ../config
 
-AM_CFLAGS = $(WARN_FLAGS) $(PIC_FLAG) -I $(srcdir)/../include -I ../libgcc
+AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
+	-I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/include
+
+AM_CFLAGS = $(WARN_FLAGS) $(PIC_FLAG)
 
 noinst_LTLIBRARIES = libbacktrace.la
 
diff --git a/libbacktrace/Makefile.in b/libbacktrace/Makefile.in
index d53ea32cc9000fb35f9d78edbb3e55b469841888..f041b5715d18d849748ffdb26b292919284066bb 100644
--- a/libbacktrace/Makefile.in
+++ b/libbacktrace/Makefile.in
@@ -256,7 +256,10 @@ top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 ACLOCAL_AMFLAGS = -I .. -I ../config
-AM_CFLAGS = $(WARN_FLAGS) $(PIC_FLAG) -I $(srcdir)/../include -I ../libgcc
+AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
+	-I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/include
+
+AM_CFLAGS = $(WARN_FLAGS) $(PIC_FLAG)
 noinst_LTLIBRARIES = libbacktrace.la
 libbacktrace_la_SOURCES = \
 	backtrace.h \