diff -uar libffi-3.0.13.orig/include/Makefile.am libffi-3.0.13/include/Makefile.am
--- libffi-3.0.13.orig/include/Makefile.am	2013-03-16 12:19:39.000000000 +0100
+++ libffi-3.0.13/include/Makefile.am	2015-10-01 12:16:50.471176047 +0200
@@ -5,5 +5,5 @@
 DISTCLEANFILES=ffitarget.h
 EXTRA_DIST=ffi.h.in ffi_common.h
 
-includesdir = $(libdir)/@PACKAGE_NAME@-@PACKAGE_VERSION@/include
+includesdir = $(includedir)
 nodist_includes_HEADERS = ffi.h ffitarget.h
diff -uar libffi-3.0.13.orig/include/Makefile.in libffi-3.0.13/include/Makefile.in
--- libffi-3.0.13.orig/include/Makefile.in	2013-03-17 23:36:21.000000000 +0100
+++ libffi-3.0.13/include/Makefile.in	2015-10-01 12:17:21.089183104 +0200
@@ -250,7 +250,7 @@
 AUTOMAKE_OPTIONS = foreign
 DISTCLEANFILES = ffitarget.h
 EXTRA_DIST = ffi.h.in ffi_common.h
-includesdir = $(libdir)/@PACKAGE_NAME@-@PACKAGE_VERSION@/include
+includesdir = $(includedir)
 nodist_includes_HEADERS = ffi.h ffitarget.h
 all: all-am
 
diff -uar libffi-3.0.13.orig/libffi.pc.in libffi-3.0.13/libffi.pc.in
--- libffi-3.0.13.orig/libffi.pc.in	2013-03-16 12:19:39.000000000 +0100
+++ libffi-3.0.13/libffi.pc.in	2015-10-01 12:16:08.287172210 +0200
@@ -1,7 +1,7 @@
 prefix=@prefix@
 exec_prefix=@exec_prefix@
 libdir=@libdir@
-includedir=${libdir}/@PACKAGE_NAME@-@PACKAGE_VERSION@/include
+includedir=@includedir@
 
 Name: @PACKAGE_NAME@
 Description: Library supporting Foreign Function Interfaces